cumulative limits would result in additional flight cancellations that
inconvenience the general public. RAA stated that the multiple limits
overlapped to a significant degree, and the numerous cumulative
regulatory restrictions would be very difficult to keep track of in
practice.
    RAA stated that the standards of other authorities were not
applicable to this rulemaking because, instead of simply being
concerned with safety, ``CAP-371 and the EASA regulations envision a
system of `fair and equitable' crew scheduling that is justified in a
European context by its intent of spreading more fatiguing assignments
among the entire flightcrew member community.'' While RAA accepted the
proposition that some cumulative restrictions were necessary, it
believed that this proposal included too many cumulative restrictions.

    As discussed above, the FAA has decided to eliminate the cumulative
duty-period limits, which should greatly simplify compliance with this
section. Thus, the only remaining cumulative limits are FDP and flight-
time limits. The FAA has decided to retain both of these cumulative
limits because (1) the FDP limits restrict the amount of cumulative
fatigue that a flightcrew member accumulates before and during flights,
and (2) the flight-time limits allow the FAA to provide air carriers
with more scheduling flexibility by setting higher cumulative FDP
limits in this rule. This additional scheduling flexibility justifies
the added complexity of the cumulative flight-time limits, which can
easily be tracked by scheduling programs currently in use throughout
the industry. The FAA also notes that complying with the cumulative
flight-time limits in addition to the FDP limits should not present a
significant burden to many air carriers because they are already
required to keep track of pilot flight time in order to comply with a
statutory provision that limits flight time on interstate domestic
flights to 85 hours per month.\76\
---------------------------------------------------------------------------

    \76\ 49 U.S.C. 42112(b)(1). This statutory provision
incorporates National Labor Board Decision number 83, which, among
other things, limits monthly flight time to 85 hours.
---------------------------------------------------------------------------

    The FAA understands that standards such as CAP-371 and EASA were
drafted to achieve goals that may be somewhat different from the safety
goals of this rule. In light of this fact and the requirements of the
Administrative Procedure Act, while the FAA has examined the provisions
of the various standards of other authorities, the FAA ultimately made
its own independent decisions based on the needs and concerns of the
stakeholders and the FAA about how to structure this rule. That is why
some of this rule's provisions are similar to other standards and other
provisions are very different from the standards adopted by other
aviation authorities.
    RAA, NACA, AMA, Boeing, and a number of air carriers opposed the
365-day cumulative flight-time limit, arguing that there was no safety-
based justification for this limit. These commenters stated that the
28-day flight-time limits, as well as the other proposed cumulative
limits, restricted cumulative fatigue to acceptable levels on a
continuing basis without the need for an annual flight-time limit. Four
individual commenters and SWAPA suggested that the 365-day flight-time
limit be increased to 1,200 hours. SWAPA noted that the proposed
regulations allow a flightcrew member to have 100 flight-time hours in
a month, and ``[i]f flying 100 hours per month for ten months in a row
does not create a cumulative fatigue problem, we find it hard to
imagine that there would be a cumulative fatigue issue in month 11 or
12.'' One individual commenter asserted that the individual monthly
flight-time limits should add up to the annual limit.
    The 1,000-hour 365-day flight-time limit comes from existing
regulations, which limit yearly flight-time to 1,000 hours and monthly
flight time to 100 hours. To meet the 1,000-hour limit, air carriers
must restrict the average monthly flight times of flightcrew members to
approximately 83 hours. However, because the 1,000-hour limit is a
yearly limit, air carriers have the flexibility to exceed the 83-hour
monthly average and fly up to 100 hours during peak months so long as
they fly a reduced number of hours during off-peak months.
    The FAA has significant operational experience with the 1,000-hour
annual limit, and based on this experience, the FAA has determined that
a flight-time average of approximately 83 hours per month is safe. For
the sake of regulatory simplicity, the FAA has also considered
eliminating the 1,000-hour annual flight-time limit and reducing the
monthly flight-time limit to 83 hours. However, the FAA ultimately
determined that such a reduction would unnecessarily limit air carriers
by prohibiting them from scheduling extra flight-time hours during peak
months. Thus, in order to preserve existing air carrier scheduling
flexibility, this rule retains the 1,000-hour flight-time limit imposed
by the existing regulations.
    A number of commenters suggested using calendar periods for
cumulative limits instead of rolling periods of hours and calendar
days. Boeing, Allegiant, and a number of individual commenters
suggested that the annual flight-time limit be based on calendar months
instead of 365 days. Boeing and Allegiant stated that the existing
regulations have a 12-calendar-month limit, and switching to a 365-day
limit would: (1) Increase costs because air carriers would have to
change their existing scheduling systems; and (2) make it more
difficult for individual flightcrew members to keep track of the annual
limit.
    Boeing also argued that the cumulative FDP limits should, for the
sake of regulatory simplicity, use 28 calendar days as a time-period
measurement instead of 672 hours. SkyWest also suggested using calendar
periods instead of hourly limits for the sake of simplicity.
Conversely, NJASAP supported the use of hourly time periods instead of
calendar days or months as a cumulative-limit measurement. IPA
supported the use of hourly time periods for daily and weekly limits,
but stated that the monthly and annual limits should be based on
calendar days. AMA also supported the proposal's use of rolling
calendar day and hourly cumulative time periods, asserting that the use
of calendar periods would be subject to abuse.
    The FAA has largely used consecutive hours to express time periods
in this section in order to create a consistent and uniform enforcement
standard. One problem with calendar periods is that different air
carriers use calendar periods in different ways. Thus, for example, one
air carrier's calendar day may start at midnight, while another air
carrier's calendar day may start at 9am.
    Another problem with calendar periods is that a single calendar
period can cover different lengths of time. Thus, a calendar month
could cover a time period ranging from 28 to 31 days. A calendar year
would also present problems if it is measured in months instead of days
because a 28-31-day monthly period would create lookback problems. To
avoid these types of issues with calendar periods, this section
expresses the cumulative time periods largely as a function of
consecutive hours, which are an unchanging uniform standard that
applies the same way to all air carriers. The FAA does not believe that
this will create an undue burden for air carriers and flightcrew
members because modern scheduling programs and spreadsheets can easily
keep track of time periods consisting of consecutive hours.
    In light of its preference for consecutive hours, the FAA has
amended subsection 117.23(b)(1) so that it expresses the corresponding
cumulative limit as a function of consecutive hours instead of calendar
days. However, the FAA has decided to retain the flight-time limit in
subsection 117.23(b)(2) as an expression of calendar days because
expressing 365 days as a function of hours would result in a very high
number of hours that would be difficult to apply in practice.
    Boeing, Kalitta Air, and Omni Air objected to the FDP limits for
the 672-hour (28-day) time period, arguing that cumulative fatigue is
already taken into account by the 168-hour cumulative limits. Boeing
stated that there is no scientific evidence ``proving that an event 672
hours ago has a predictable effect on alertness now.'' Conversely, NACA
and a number of labor groups

supported the concept of cumulative limits for 28-day periods.
    The different cumulative FDP limits work on the same flexibility
principle as the 672-hour and 365-day cumulative flight-time limits.
The cumulative FDP limit for the 672-hour period is 190 hours. To
comply with this 190-hour limit, an air carrier has to average
approximately 47.5 cumulative hours of FDP in each 168-hour period.
However, the 60-hour cumulative FDP limit for each 168-hour period
allows air carriers to exceed the 47.5-hour FDP average during peak
weeks as long as they go below this average during off-peak weeks. Just
like the different flight-time limits, this system provides air
carriers with scheduling flexibility while keeping the average weekly
cumulative FDP times within acceptable bounds.
    APA asked that the FAA add in a cumulative flight-time limit for
the 168-hour period, arguing that, without this limitation, air
carriers could schedule a significant amount of flight time in this
period of time.
    The existing regulations for domestic and flag operations impose
30-32 hour cumulative flight-time limits for 7-day periods. However,
the existing regulations for supplemental operations do not impose
cumulative flight-time limits for 7-day periods. Based on its
operational experience administering supplemental operations without a
7-day cumulative flight-time limit, the FAA has determined that there
is no need to impose a 168-hour flight-time limit in addition to the
other cumulative limits in this rule.
    NACA, NAA, and Northern Air Cargo asked the FAA to increase the
cumulative FDP limits to match the limits suggested for cumulative duty
periods, arguing that the proposed limits did not take into account the
needs of supplemental operations. Conversely, AAC, AFA-CWA, ALPA, and a
number of other union groups asserted that the proposed cumulative
limits were appropriate. ALPA stated that the proposed limits should
neither be expanded nor reduced and AAC stated that the FAA should not
impose additional cumulative limits.
    The proposed cumulative-duty-period limits in this rule were higher
than the proposed cumulative FDP limits because duty encompassed more
non-flight activities than FDP. Since most of the additional non-flight
activities covered by duty did not raise significant fatigue-related
concerns, the FAA set the cumulative-duty-period limits at a higher
level. As discussed above, because duty periods did not have a
significant effect on aviation safety independent of FDPs, cumulative-
duty-period limits have been eliminated from this rule.
    The FAA has also decided against increasing the proposed cumulative
FDP limits. Because this rule retains cumulative flight-time limits,
the cumulative FDP limits in this section are set at sufficiently high
levels that should allow air carriers full utilization of the
cumulative flight-time limits in this section. Thus, for example, the
cumulative FDP limit for the 672-hour period is 190 hours, which is
almost double the cumulative flight-time limit of 100 hours for this
time period. Because the proposed cumulative FDP limits were already
set at relatively high levels, the FAA has decided against increasing
these limits further without additional FRMS-provided data.
    NJASAP asked whether the time spent on reserve will count towards
the cumulative FDP limits of this section. Only the time that is spent
on airport/standby reserve is considered to be FDP. As such, only the
time that is spent on this type of reserve counts toward the cumulative
FDP limits of this section.

O. Rest

    Rest is a significant element of this rule because it is the most
critical component of fatigue mitigation. In this rulemaking, the FAA
has addressed the following concerns with the present regulatory scheme
governing rest: (1) Part 121, subparts Q, R, and S provide rest limits
within a 24-hour period, however certificate holders conducting
operations with airplanes having a passenger seating configuration of
30 seats or fewer and a payload capacity of 7,500 pounds or less, may
comply with the less stringent requirements of 14 CFR 135.261 and
135.273; (2) the lack of any mechanism to assure that rest is provided
prior to flight; and (3) no clear requirement that the 9 hour rest
period must provide for an 8 hour sleep opportunity. The FAA also
sought to specifically articulate what it means for a flightcrew member
to be free from duty, as this and other related issues under the
current scheme have resulted in more than 55 legal interpretations
issued by the FAA regarding rest.
    Sleep science has settled on the following points: The most
effective fatigue mitigation is sleep; an average individual needs to
have an 8-hour sleep opportunity to be restored; 8 hours of sleep
requires more than 8 hours of sleep opportunity; and daytime sleep is
less restorative than nighttime sleep.\77\ For most people, 8 hours of
sleep in each 24 hours sustains performance indefinitely.\78\ There is
a continuous decrease in performance as sleep is lost. Examples of this
reduction in performance include complacency, a loss of concentration,
cognitive and communicative skills, and a decreased ability to perform
calculations. All of these skills are critical for aviation safety.\79\
---------------------------------------------------------------------------

    \77\ Akerstedt, T., & Gillberg, M. (1981). The circadian
variation of experimentally displaced sleep. Sleep, 4 (2), 159-1659.
Akerstedt, T., & Gillberg, M. (1990). Subjective and objective
sleepiness in the active individual. International journal of
neuroscience, 52 (1-2), 29-37. Gander, P.H., De Nguyen, B.E.,
Rosekind, M.R., & Connell, L.J. (1993). Age, circadian rhythms, and
sleep loss in flight crews. Aviation, Space, and Environmental
Medicine, 64 (3), 189-195.
    \78\ Rosekind, M.R., Gander, P.H., Gregory, K.B., Smith, R.M.,
Miller, D.L., Oyung, R., Webbon, L.L., & Johnson, J.M. (1996).
Managing fatigue in operational settings 1: Physiological
considerations and countermeasures. Behavioral Medicine, 21, 157-
165.
    \79\ Caldwell, J.A., Mallis, M.M., Caldwell, J.L., Paul, M.A.,
Miller, J.C., & Neri, D.F. (2009). Fatigue countermeasures in
aviation. Aviation, Space, and Environmental Medicine, 69 (1), 29-9.
---------------------------------------------------------------------------

    In the Flight Time ARC meetings, scientific presenters stated that
during long pairings with significant time zone shifts, a minimum of 24
hours off would be necessary for flightcrew members to find an adequate
sleep opportunity, and sufficient time free from duty.\80\ A minimum of
two nights of sleep might be necessary to acclimate to a different time
zone.\81\
---------------------------------------------------------------------------

    \80\ Gander, P.H., Myhre, G., Graeber, R.C., Anderson, H.T., and
Lauber, J.K. (1985). Crew factors in flight operations: I. Effects
of 9-hour time-zone changes on fatigue and the circadian rhythms of
sleep/wake and core temperature (NASA/TMm 1985-88197). Moffett
Field, CA. NASA Ames Research Center.
    \81\ Lamond, N., Petrilli, R.M., Dawson, D., and Roach, G.D.
(2006). Do short international layovers allow sufficient opportunity
for pilots to recover? Chronobiology International, 23(6), 1285-
1294. Lamond, N., Petrilli, R.M., Dawson, D., and Roach, G.D.
(2005). The impact of layover length on the fatigue and recovery of
long-haul flight crew. Adelaide/Whyalla, Australia: University of
South Australia, centre for Sleep Research.
---------------------------------------------------------------------------

    The scientific presenters also noted that an individual's circadian
clock is sensitive to rapid time zone changes. They added that long
trips present significant issues requiring mitigation strategies.\82\
Twenty-four or 48 hours of rest may not be adequately restorative
during a trip pairing where a flightcrew member is working 20 days
separated by 24-hour layovers. In some cases, shorter rest periods,
such as 18 hours or less,

may be more restorative because of circadian issues.
---------------------------------------------------------------------------

    \82\ See also, Gander, P.H., Graeber, R.C., Connell, L.J., and
Gregory, K.B. (1991). Crew factors in flight operations: VIII.
Factors influencing sleep timing and subjective sleep quality in
commercial long-haul flight crews (NASA/TMm 1991-103852). Moffett
Field, CA: NASA Ames Research Center. Rosekind, M.R., Gander, P.H.,
Gregory, K.B., Smith, R.M., Miller, D.L., Oyung, R., Webbon, L.L.
and Johnson, J.M. (1996). Managing fatigue in operational settings
2: An Integrated Approach. Behavioral medicine, 21, 166-170.
---------------------------------------------------------------------------

    In the NPRM, the FAA proposed requirements for FDP/reserve period
rest, acclimation rest upon returning to home base, and reduced rest
under limited conditions. For pre-FDP/reserve assignments, the FAA
proposed that prior to accepting a reserve duty period or FDP, the
flightcrew member must be given a rest period of at least 9 consecutive
hours measured from the time the flightcrew member reaches the hotel or
other suitable accommodation.
    In addition, the FAA proposed that a flightcrew member must be
given at least 30 consecutive hours free from all duty in any 168
consecutive hour period prior to beginning a reserve period or FDP.
This provision included two exceptions. The first is that during an FDP
or series of FDPs, if a flightcrew member crosses more than 4 time
zones on FDPs that exceed 168 consecutive hours, that flightcrew member
must be given a minimum of three physiological nights' rest upon return
to home base. The second is if a flightcrew member is operating in a
new theater, he or she must receive 36 consecutive hours of rest in any
168 consecutive hour period.
    The proposal also would have permitted a one-time reduction in the
pre-FDP/reserve rest period from 9 to 8 consecutive hours in any 168
consecutive hour period. Additionally and in the event of unforeseen
circumstances, the pilot in command and the certificate holder could
reduce the 9 hour rest period to 8 consecutive hours. Lastly, the FAA
proposed that during a rest period, the certificate holder could not
assign and no flightcrew member could accept any assignment for reserve
or duty.
    Commenters raised two issues concerning the proposed pre-FDP/
reserve rest requirement. The first issue was the FAA's selection of
the 9 hour rest period. The second issue was the beginning measurement
of the rest period. As these two issues interrelate, the comments for
both are summarized below.
    In the NPRM, the FAA noted that the ARC members supported a
domestic rest requirement of 10 hours that was comprised of an 8 hour
sleep opportunity, with 30 minutes on each end for transportation and
30 minutes on each end for physiological needs such as eating,
exercising and showering. The ARC members also discussed whether the
rest requirement should be increased to 12 hours for international
operations. The ARC members cited the following reasons for the two
added hours for international operations: To provide a longer layover
rest period for non-acclimated flightcrews; potential to address
increased stress associated with communicating with air traffic control
in countries where English is not the native language; and time to
transit customs/immigration or travel a long distance to hotel
accommodations in foreign destinations.
    The FAA decided not to propose two different rest periods and
instead put forth one standard rest period for all operations. The FAA
was not persuaded that added rest was necessary to deal with air
traffic control communications in a foreign airspace. Furthermore,
acclimation for determining the length of an FDP was addressed by other
provisions in the proposal. Lastly, the time to clear customs/
immigration was addressed by refining the point where rest begins.
    The FAA received over 2,500 comments from individuals who contend
that the proposed 9 hour rest period was inadequate and did not allow
sufficient time to eat, bathe, exercise or unwind, and still have an
opportunity for 8 hours rest. The NTSB strongly encouraged the FAA to
increase the duration of the required rest period to accommodate an
opportunity for 8 hours of sleep. CAPA, APA, and SWAPA pointed to FAA
Advisory Circular No. 120-FIT, which recognizes that 9 hours of rest
typically does not yield 9 or 8 hours of sleep. Peninsula Airways, the
Families of Continental Connection Flight 3407, APA, IPA, Southwest
Airlines, SWAPA, AE and Delta Air Lines supported a 10 hour rest period
for domestic operations.
    Approximately 150 individual commenters believe that the rest
period for international operations should be 12 hours. Other
commenters suggested varying times of 13, 14, and 20 hours respectively
for operations that travel across multiple time zones. Pinnacle
Airlines suggested a rest period of 48 hours. ALPA advocated a minimum
of 13 hours rest period for flightcrew members that fly to a new
theater--once they become acclimated, they go back to 10 hours rest.
ATA commented that the terminology should be changed from ``domestic''
and ``international'' to ``in theater'' and ``in new theater'' (and use
the term ``theater'' as defined in the NPRM). ATA argues that the
distinction of domestic/international in this context is not relevant
and provides the following example. A pilot completing a north-south
flight between the U.S. mainland and Canada or the Caribbean that
crosses no time zones should not be treated differently than one that
makes the same north-south trip within the continental U.S. APA, CAPA,
SWAPA and Kalitta Air endorsed a 12 hour rest period for non-acclimated
flights.
    Conversely, Hawaiian Airlines supported the single hour rest
requirement of 9 hours, and commented that this provision is not
competitively disadvantageous for its operations. CCIA supported a
longer rest period than that provided under the present regulations.
American Airlines supported the proposed 9 hours and Alaska Airlines
simply argued that the proposed rest provisions should be withdrawn,
reevaluated, and republished for comment.
    For the NPRM, the FAA chose to begin the rest period at the time
that the flightcrew member reached the hotel or suitable accommodation.
The basis for this tentative decision largely rested on the premise
that transportation is not rest and therefore, cannot be factored into
the rest period. In addition, the time spent in transportation may vary
widely.
    Commenters were divided with respect to the proposal's measurement
of when the rest period begins. Most commenters representing industry
did not support measuring the rest period from the time the flightcrew
member reached the hotel or suitable accommodation. These commenters
described this aspect as wholly unworkable, and open to too many
variables that would be beyond the certificate holder's control, e.g.
vehicular breakdowns, accidents, unexpectedly heavy traffic and lost or
overbooked facility reservations. In addition, they state that the
certificate holder would be responsible to account for the flightcrew
member's whereabouts throughout the rest period. They argue that the
certificate holder's responsibility is to control the scheduling of
compliant rest periods, not to control an individual's private life and
activities when off duty.
    The labor organizations and the Families of Continental Connection
Flight 3407 supported the proposed beginning measurement of the rest
period. These entities were concerned with being able to ``get 9 hours
behind the door,'' which would provide a better opportunity for a
meaningful 8 hour sleep opportunity. APA also recommended, in addition
to the proposal, that the FAA add language that to be compliant with
this rest requirement, the hotel room must be available for immediate
occupancy upon arrival. A number of pilot groups commented that rest
time can be spent waiting for check-in or delay in getting room keys.
Conversely, a number of certificate holders stated that check-in
sometimes occurs in the vehicle on the

way to the hotel, or that hotels offer separate check-in counters for
flightcrew members.
    As discussed above, the FAA was not persuaded at the NPRM stage to
pursue a separate rest period for international operations. The agency
concluded that an additional two hours of rest was not warranted to
address potential fatigue from communicating with air traffic
controllers in foreign airspace, nor did it support added rest due to
time to clear customs and immigration. A number of airports have custom
and immigration queues devoted to processing flightcrew members
quickly.
    The adopted regulations providing FDP limits for augmented and
unaugmented operations address acclimation. For an unacclimated
flightcrew member, the maximum flight duty period in Table B is reduced
by 30 minutes and the flightcrew member enters the applicable FDP table
based on the local time at the theater in which the flightcrew member
was last acclimated. Under these provisions, the determined FDP limits
take into account the flightcrew member's WOCL and general circadian
rhythm. As long as the flightcrew member is receiving an 8 hour sleep
opportunity, the nature of whether the FDP was international is not
relevant. The FAA has decided to retain a single standard rest period
provision that applies to all FDPs and reserve periods.
    Based on the comments received from the certificate holders, the
FAA agrees that using the time when a flightcrew member reaches the
hotel or other suitable accommodation would present more issues for
implementation than it actually solved. The FAA's main objective with
this provision was to ensure that flightcrew members have an 8 hour
sleep opportunity. Building from that and mindful of the comments
received, the FAA has decided to adopt a 10 consecutive hour rest
requirement that immediately precedes the beginning of a reserve or FDP
measured from the time the flightcrew member is released from duty. At
this point, if the flightcrew member cannot have 8 uninterrupted hours
of rest opportunity, the flightcrew member cannot report for the
assigned FDP until he/she receives that rest. If the reason for the
shortened rest opportunity is travel delays, reservation confusion, or
the flightcrew member's actions, the certificate holder is free to
address the root cause. However, it must provide the required 8-hour
rest opportunity.
    The FAA finds that the modifications adopted in this rule address
concerns raised by the labor organizations, the NTSB and the Families
of Continental Connection Flight 3407 concerning an actual 8 hour
opportunity devoted to sleep. Furthermore, it provides reasonable time
for travel to the hotel, check-in, and meals. The FAA acknowledges
there will be unforeseen circumstances that are beyond the control of
either the certificate holder or the flightcrew member and these
situations are difficult to capture in a regulatory standard. In
situations such as this, where the flightcrew member ultimately is not
provided with the necessary rest period and/or sleep opportunity, the
flightcrew member must notify the certificate holder that he/she will
be unable to obtain the required rest. It is advisable that the
flightcrew member alert the certificate holder as soon as possible in
order for the certificate holder to make alternative arrangements that
may include adjusting the next FDP or flight departure time, or calling
in a reserve crew.
    NACA, Kalitta Air, NAA and Atlas disagree with the proposed rest
requirement for a flightcrew member that crosses more than four
different time zones and is away from home base for more than 168
consecutive hours. These commenters specifically state that three
physiological nights' rest is excessive, not based on science, and that
only a 30 hour rest period is necessary because fatigue has been
mitigated throughout the flightcrew member's trip. They also commented
that there is no justification for a different standard for rest at
home and that rest at home generally is more fatigue mitigating than
rest at operating locations. UPS also objected to the use of three
physiological nights' rest upon return to home base. UPS contends that
rest at home should be treated the same as rest in layover cities and
that off-duty time between pairings ``is traditionally, and correctly,
addressed via the collective bargaining process.'' \83\
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    \83\ The FAA notes that not all pilot groups are organized and
therefore, do not have a collective bargaining process.
---------------------------------------------------------------------------

    NACA and Kalitta Air also recommended a reduced rest period of 30
hours, instead of the proposed 36 consecutive hours of rest, in any 168
consecutive hours for flightcrew members operating in a new theater.
    The FAA adopts as proposed the requirement that a flightcrew member
must be given at least 30 consecutive hours free from duty in any 168
consecutive hour period. The NPRM included two exceptions to this
requirement. The first exception was a longer rest period upon return
to home base after a flightcrew member has been away for more than 168
consecutive hours and has crossed at least four time zones. The second
exception was for flightcrew members operating in a new theater to
receive 36 hours of rest.
    In the NPRM, the FAA stated that it was ``proposing to require a
greater rest opportunity when a flightcrew member has been away from
his or her home base for more than 168 hours. In this instance, the FAA
proposes to require a rest period that includes 3 physiological nights,
rather than 36 hours free from duty or permitting the flightcrew member
to fly during that approximately 72 hour period.'' 75 Fed. Reg. 55862.
The corresponding regulatory text proposed three physiological nights'
rest. By using three physiological nights' rest, the FAA intended this
provision to provide for a minimum 56-hour rest period, as indicated in
the NPRM preamble discussion. As proposed, the regulatory text would
permit a flightcrew member, upon return to home base after 168 hours
away from home and crossing numerous time zones, to be assigned to FDPs
that would occur during the day only, but require the flightcrew member
to sleep at home for three nights. The intention was for that
flightcrew member to receive a minimum of 56 consecutive hours of
rest.\84\
---------------------------------------------------------------------------

    \84\ If a flightcrew member begins this rest at 1 a.m. on day 1
and concludes this rest at 7 a.m. on day 3, this provides a minimum
of 56 hours of rest.
---------------------------------------------------------------------------

    The FAA does not agree with the commenters that a 30 consecutive
hour rest period is adequate for flightcrew members that have flown a
schedule that has the flightcrew member crossing several time zones and
is away from home for more than 168 hours. This longer rest period
serves an important purpose. The longer rest period provides a recovery
period that facilitates the restoration of the flightcrew member's
circadian rhythms. Sleep loss or sleep disturbance can significantly
deteriorate performance. Moreover, performance impairment can occur
when the sleep-wake cycle has only been phase-advanced by 2-4 hours and
maintaining a normal sleep period. These results suggest that
performance deterioration can directly result from circadian rhythm
disturbance and not only solely from sleep loss that would occur with
time zone changes. The onset of sleep and the duration of that sleep
can ``* * * depend upon the circadian body temperature phase and
provides a physiological basis for the performance deterioration or
circadian desynchronization.'' \85\ Typically, flights

across multiple time zones involve a differential restructuring in an
internal circadian desynchronization and associated symptoms.\86\
---------------------------------------------------------------------------

    \85\ Winget CM, Deroshia CW, Markley CL, Holley DC. (1984). A
review of human physiological and performance changes associated
with desynchronosis of biological rhythms. Aviat. Space Envion. Med.
1984; 55:1085-96, p. 1090.
    \86\ Id. at p. 1085.
---------------------------------------------------------------------------

    Flightcrews routinely deal with multiple time zone adjustments and
work schedule changes. Flight operations involve night and ``shift
work'' in general and exposures to different social and environmental
cues can vary after both the outbound and inbound segments of flights,
which can make the prediction of an individual's resynchronization very
difficult. ``Advances'' in rhythms occur with eastward travel and
``delays'' with westward travel. Flights of multiple time zones involve
circadian adjustments that vary in length depending on the direction of
travel. Physiological, performance, and subjective measures are also
found to adjust at different rates to changes in time zones.\87\
---------------------------------------------------------------------------

    \87\ Wegmann HM, Klein KE. Jet lag and aircrew scheduling. In:
Folkard S, Monk TH, eds. Hours of work. Chichester; John Wiley &
Sons Ltd., 1985; 263-76.
---------------------------------------------------------------------------

    Some studies also indicate that a complete adjustment following six
time zone transitions was found to take up to 13 days after eastbound
flights, and 10 days in westbound flights.\88\ Other research indicates
that there is considerable variation in the rates of resynchronization
of individual rhythms. After a time shift, such as that experienced by
pilots flying several days in a new theater, with all rhythms phase-
adjusted, upon return to their domicile, a resynchronization process
begins anew and is not complete until each rhythm has rephrased back to
the home time zone. ``The different rates of rhythm readjustment lead
to transient internal dissociation, in which the normal phase
relationships between rhythms are disrupted.'' \89\
---------------------------------------------------------------------------

    \88\ Wegmann HM, Gundel A, Naumann M, Samel A, Schwartz E,
Vejvoda M. Sleep, sleepiness, and circadian rhythmicity in aircrews
operating on transatlantic routes. Aviat. Space Environ. Med. 1986;
57(12, Suppl.); B53-64.
    \89\ Winget et al. (1984) at page 1087.
---------------------------------------------------------------------------

    Consequently, the FAA finds it critical to address the
desynchronization/resynchronization of circadian rhythms that occurs
when transiting multiple time zones. This recovery rest not only
acclimates flightcrew members but also resets the circadian rhythms
before the next assigned flight duty period. The FAA corrects the
regulatory text to provide for a 56 consecutive hour rest instead of
the three physiological nights' rest, as previously discussed.
Depending upon when the rest period begins, this requirement provides
for 2 to 3 physiological nights' rest.
    With respect to the NACA and Kalitta's concern with using the
higher value of 36 hours rest instead of 30 hours to acclimate, the FAA
is not persuaded by the comment. The ARC members agreed that a
flightcrew member should have at least 30 to 36 continuous hours free
of duty (rest) in any 168 consecutive hours and that once a flightcrew
member is given this rest, he or she is considered acclimated to the
local time. As rest is critical, the FAA choose to propose the more
conservative 36 hour rest period, given that adequate rest provides the
most fatigue mitigation. NACA and Kalitta do not offer information
supporting 30 hours instead of 36 hours. However, an approved FRMS may
appropriately determine whether additional mitigations may permit the
limited reduction in rest.
    For clarity, the regulatory text in this section has been
restructured. Paragraph (b) of this section adopts the 30 consecutive
hour minimum rest requirement per week as proposed. Under paragraph
(c), if a certificate holder gives a flightcrew member operating in a
new theater 36 consecutive hours of rest, then that flightcrew member
is acclimated and must enter the FDP Table for his/her next assignment
as acclimated to the local time in that new theater. A certificate
holder does not need to provide the 36 hour rest once a flightcrew
member is in a new theater unless the carrier wants to acclimate that
flightcrew member. The flightcrew member may be given a 10 hour rest
period in accordance with paragraph (e) of this section and then be
assigned a subsequent FDP based on the home base time. However, if the
flightcrew member has received 36 consecutive hours of rest, that
flightcrew member is acclimated at that point to the new theater, and
subsequent FDP assignments must be made according to the acclimated
time. The text also specifies that if a flightcrew member has received
36 consecutive hours of rest under this paragraph, then that rest meets
the requirements of paragraph (b) for the required rest in any 168 hour
period and that resets the 168 hour period. Paragraph (d) now contains
that provision that requires at least 56 consecutive hours of rest if a
flightcrew member traverses 60[deg] longitude \90\ during an FDP or a
series of FDPs that require him or her to be away from home base more
than 168 consecutive hours. This rest must encompass three
physiological nights' rest based on local time.
---------------------------------------------------------------------------

    \90\ This change is consistent with the modification to the term
theater in the definitions section, discussed earlier.
---------------------------------------------------------------------------

    ALPA, APA, CAPA, and SWAPA argued that where flightcrew members are
not acclimated, a recovery period must be provided upon return to home
base to ensure a flightcrew member's body clock has recovered home base
local time before the start of the next day. They propose that Table F,
provided below, be used to determine the number of nights required to
re-acclimate. They also propose that Table F be used to provide
``recovery rest'' for time away from home when operating in a different
theater for less than 168 consecutive hours away from home. They cite
the current regulations \91\ as providing this rest for international
operations over a period less than 168 consecutive hours.
---------------------------------------------------------------------------

    \91\ See 14 CFR 121.483, 121.485, 121.523 and 121.525.

---------------------------------------------------------------------------

[GRAPHIC] [TIFF OMITTED] TR04JA12.001

    The FAA cannot support the inclusion of Table F. First and as a
practical matter, it is not clear that the Table could be accommodated
given the rest period that was proposed without seriously constraining
the certificate holder's ability to schedule operations. As discussed
previously, the FAA agrees and adopts a provision that specifically
addresses the resynchronization of circadian rhythms. That rest
however, must also be balanced with the certificate holder's
flexibility to schedule operations, particularly those carriers
conducting supplemental operations. The FAA used 168 hours as the
minimum trigger point for when this rest must be provided for
flightcrews returning home after completing FDPs that crossed multiple
time zones. Under Table F, flightcrew members would have to be provided
a minimum of two nights' rest at home every week. This is an
unrealistic constraint on the certificate holder's ability to set and
maintain a schedule. Under the concept furthered by this rulemaking,
the cumulative limits on FDP during the same 168 hour period, coupled
with cumulative rest requirement, should adequately mitigate the effect
of cumulative fatigue.
    Not unexpectedly, the provisions proposed in the NPRM permitting a
limited reduction in rest generally were opposed by the entities
representing labor groups and either supported or expanded by the
industry groups. ALPA accepted the proposal. SWAPA commented that
reduced rest should never be permitted since science supporting reduced
rest assumes that one is starting from a full sleep bank, which is not
always the case. SWAPA further commented that reduced rest is likely to
follow an extended FDP and that if the FAA retains a reduced rest
provision it should never be permitted after an FDP has been extended
past the maximum provided in Table B. APA only supports reduced rest if
restorative rest is provided. In addition, APA argues that if the FAA
allows a reduction in rest it should be limited to only once in a 168
consecutive hour period, due to unforeseen circumstances subject to
pilot in command concurrence, and never if associated with an extended
FDP. FedEx ALPA argued that only a one-hour reduction in rest be
permitted and only in cases of unforeseen circumstances. AE supports a
permitted one-hour reduction in rest. AA supports the one-hour
reduction but never on consecutive nights. Delta commented that the
once in 168 consecutive hour period be reset after a 30-hours rest is
given.
    Conversely, UPS supported multiple reductions in rest without
concurrence by the pilot in command. UPS contends that one reduction in
a 168 consecutive hour window simply is not feasible. UPS also argues
that requiring PIC concurrence will complicate the certificate's holder
ability to utilize the reduced rest provisions and its ability to
return a disrupted system back to a more normal state.
    In view of the comments, the FAA has decided to remove the
provisions that would permit a reduction in rest. As one of the stated
goals of this rulemaking was to ensure that flightcrew members had an
eight hour sleep opportunity, the FAA has reconsidered incorporating
criteria in the regulations to permit a reduction in this sleep
opportunity. While it is reasonable to anticipate that unforeseen
circumstances may warrant a limited extension of an FDP, particularly
for situations that arise after takeoff, the flightcrew members at this
point have already had the benefit of an eight hour rest opportunity.
The FDPs limits implemented by this rule were derived under the premise
that flightcrew members were reporting for duty with a full rest.
Permitting reduced rest undercuts that premise. This rule includes
provisions for extensions of FDPs and flight time, as necessary to
accommodate the situations that cannot be planned. Otherwise,
certificate holders should not be scheduling FDPs to the point that a
rest period needs to be reduced.

P. Deadhead Transportation

    In the NPRM, the FAA proposed that all time spent in deadhead
transportation is duty. The FAA further proposed that time spent in
deadhead transportation would be considered part of an FDP if it
occurred before a flight segment without an intervening

required rest period. Lastly, the proposal provided a rest requirement
for deadheading flightcrew members: the time spent in deadhead
transportation during a duty period may not exceed the flight duty
period in Table B for the applicable start time plus 2 hours unless the
flightcrew member is given a rest period equal to the length of the
deadhead transportation but not less than the required rest in Sec.
117.25 upon completion of such transportation.
    Several commenters contend that this proposed rest requirement
should be deleted because it is punitive and not supported by science.
They argue that this provision implies that the certificate holder
should prevent a flightcrew member from deadheading home at the end of
an FDP, even if the flightcrew member requests to do so.
    The FAA has made changes to the section addressing deadhead
transportation. Paragraphs (a) and (b) of proposed Sec.  117.31 have
been moved. Paragraph (a) provided that all time spent in deadhead
transportation is duty and that statement is relocated to the
definition for deadhead transportation. Paragraph (b), which provided
that deadhead transportation is part of an FDP if it occurred before a
flight segment without an intervening required rest period, is deleted
as that information is already contained in the definition of the term
``flight duty period.''
    The FAA agrees with the commenters that the proposed text for Sec.
117.29(c), Deadhead transportation, does not correctly articulate the
purpose of rest relative to deadhead transportation. The rest is
appropriate if the deadhead transportation occurs prior to the FDP. The
situation that FAA sought to address in the NPRM was a flightcrew
member deadheading on a long flight and then going onto a FDP without
the appropriate rest. The language as proposed would require a rest
period for a flightcrew member who is deadheading home after completion
of an FDP. The FAA has corrected the regulatory text to provide that
before beginning a flight duty period, if a flightcrew member has
engaged in deadhead transportation that exceeds the applicable flight
duty period in Table B, the flightcrew member must be given a rest
period equal to the length of the deadhead transportation but not less
than 10 consecutive hours.

Q. Emergency and Government Sponsored Operations

    This rulemaking also addresses various supplemental operations that
require flying into or out of hostile areas, and politically sensitive,
remote areas that do not have rest facilities. These operations range
from moving armed troops for the U.S. military, conducting humanitarian
relief, repatriation, Air Mobility Command (AMC), and State Department
missions.\92\ The discussions during the ARC recognized that these
operations are unique and need to be specifically addressed in this
rulemaking. Flights operated by a certificate holder under contract
with a U.S. Government agency must comply with the flight and duty
regulations in parts 121 and 135, as appropriate, unless the
Administrator has granted a deviation under 14 CFR 119.55 or 14 CFR
112.57.
---------------------------------------------------------------------------

    \92\ This could also apply to the Civil Reserve Air Fleet
(CRAF). However CRAF is only activated by presidential order in a
time of war. The last time CRAF was activated was in 2003. Currently
no operations are being conducted under the CRAF program.
---------------------------------------------------------------------------

    The FAA proposed that certificate holders may extend the applicable
maximum FDPs to the extent necessary to allow flightcrew members to fly
to a destination where they can safely be relieved from duty by another
flightcrew or can receive the required rest before beginning the next
FDP. Upon reaching the destination, the flightcrew members will receive
the required rest, which would be equal to the length of the actual FDP
or 24 hours, whichever is less. Furthermore, the proposal would not
permit extensions of the cumulative FDP or cumulative flight time
limits. In the event that an FDP was extended pursuant to this section,
the NPRM provided reporting requirements.
    A number of commenters disagreed with the FAA's use of the title
``Operations in unsafe areas'' as the title of this section.
Commenters, including UPS, Atlas Air, NAA, NACA, and NAC recommended
various terms instead such as ``Unique areas,'' ``Enhanced Security
Consideration Area: Prescriptive Exemption,'' and ``Designated Areas.''
    In addition, Atlas questioned the FAA's statement that under this
section, the flightcrew members' FDP can be extended to permit them to
continue the flight operation and land at the nearest suitable airport.
See FAA Response to Clarifying Questions at page 24. Atlas commented
that this airport may not be operationally feasible or economically
viable.
    RAA commented that operations may need to use this section to
rapidly remove or recover aircraft and crews from an airport about to
be impacted by a heavy storm, hurricane, or blizzard.
    In the NPRM, the preamble discussion for this proposed section was
titled ``Exception for Emergency and Government Sponsored Operations.''
The FAA regrets that the title was not carried over to regulatory text.
Introducing the term ``unsafe areas'' could be subject to differing
interpretations within the industry. Section 117.29 is now titled
``Emergency and government sponsored operations,'' which is an accurate
depiction of the operations addressed in this section and is consistent
with the discussion of the proposal.
    The purpose of this section is to address true emergency situations
and operations that are being conducted under contract with the U.S.
Government that pose exceptional circumstances that would otherwise
prevent a flightcrew member from being relieved from duty or safely
provided with rest at the end of the FDP. This section is not meant to
address self-induced emergencies that arise from inadequate planning.
Certificate holders must be responsible for having appropriate onboard
rest facilities or the proper number of flightcrew members available
for the length of the duty day, if necessary.
    The FAA reviewed the regulatory text and determined that this
clarification warrants certain modifications. First, the applicability
provision of this section now specifically articulates the two
categories of operations that are affected. This section applies to
operations conducted pursuant to contracts with the U.S. Government
department and agencies. A number of these types of flights are
conducted under contract with the Departments of Defense, State,
Homeland Security, Justice, FEMA, and Customs and Immigration. This
provision is not limited to operations conducted pursuant to Sec.
119.55, which permits certificate holders to deviate from the
requirements of parts 121 and 135, as authorized by the Administrator
in order to conduct operations pursuant to a military contract. Rather,
this provision could apply to multiple government agencies depending on
the mission. The FAA also recognizes that there are operations in which
the Department of Defense may need relief from the flight and duty
regulations even though the circumstances do not meet the certification
requirements of Sec.  119.55.
    This section also applies to operations conducted pursuant to a
deviation issued by the Administrator under Sec.  119.57 that
authorizes an air carrier to deviate from the requirements of parts 121
and 135 to perform emergency operations. For example, under this
section the FAA issued operations specifications for emergency
operations

during Hurricane Katrina to allow humanitarian flights into and out of
New Orleans. This authority is issued on a case-by-case basis during an
emergency situation as determined by the Administrator.
    Upon review, the FAA concludes that these two categories are the
only types of operations that warrant separate consideration because of
the unique operating circumstances that otherwise limit a certificate
holder's flexibility to deal with unusual circumstances. Therefore,
unless a certificate holder's operations fall under either category,
the ability to extend an FDP under this section does not apply.
    In response to RAA's comment as to this section regarding moving
aircraft and crews from an airport about to be impacted by a blizzard
or hurricane, these certificate holders have recourse to extend an FDP
as necessary under Sec.  117.19. The FAA's modifications to this
section are to allow for true emergency situations and to address the
uniqueness of certain government contract operations.
    Second, this section adopts the provision permitting the FDP and
the flight time for a particular operation to be extended if deemed
necessary by the pilot-in-command. This provision was slightly modified
to allow for an extension to the flightcrew members' flight time
limitations if necessary. In addition, the pilot-in command is given
the authority to determine the closest destination to safely land the
aircraft and allow for the flightcrew to be relieved and afforded the
proper rest. The FAA does not expect the flightcrew to extend the FDP
simply to complete the next commercially scheduled leg.\93\
---------------------------------------------------------------------------

    \93\ FAA Response to Clarifying Questions.
---------------------------------------------------------------------------

    Third, the FAA has addressed the reporting requirements for
situations when a FDP is extended. Under the NPRM, the FAA proposed two
different reporting requirements depending upon whether the operation
was conducted pursuant to a U.S. government contract. This section has
been modified to incorporate the reporting requirements listed in Sec.
117.19 Flight Duty Period Extensions. Therefore, the certificate holder
must file within 10 days any extended FDP and flight time that exceed
the maximum permitted under the adopted regulations. The report must
contain a description of the extended FDP and flight time limitations
and the circumstances surrounding the situation requiring the
extension. In addition, if the circumstances surrounding the situation
were within the certificate holder's control, the report must contain
information on the certificate holder's intended course of corrective
action. This action must be implemented within 30 days from the date
that the FDP was extended.
    The reporting of FDP extensions in this manner can facilitate the
certificate holder and the FAA's determination as to whether the
certificate holder is properly planning its operations and mitigating
the chances of its flightcrews exceeding the FDP limits. If a
certificate holder cannot restructure its operations so that very few
of these operations need to take advantage of this provision, the
certificate holder is advised to develop an FRMS to address these
operations.
    Several commenters were concerned with the proposal's prohibition
on any extension of the cumulative FDP and flight time limits if an
extension to a daily FDP was triggered under this section. The FAA
partially agrees with the commenters. For operations conducted pursuant
to a deviation authorized under Sec.  119.57, the FAA agrees that these
circumstances may necessitate the flightcrew member's ability to exceed
the cumulative flight time and FDP limitations respectively found in
Sec. Sec.  117.23(b) and (c). Therefore, this section permits an
extension of the flightcrew member's FDP and flight time limitation
even if it exceeds the cumulative requirements in 117.23 for operations
that are conducted pursuant to a deviation authorized under Sec.
119.57.
    The FAA does not make such finding with respect to other operations
conducted pursuant to a U.S. government contract. Even though these
operations may fly into and out of hostile areas or areas that preclude
the flightcrew members from proper rest facilities, the certificate
holder is well aware of the operating environments where it is agreeing
to conduct such operations. Therefore, these situations must be taken
into account during the planning stages. A certificate holder needs to
have considered and planned for whether the operations under contract
will necessitate staging crews at other airports or installing rest
facilities onboard the aircraft to enable augmentation, in order to
ensure that flightcrews will not exceed FDP limit. For these
operations, the cumulative limits on FDP and flight time apply.

R. Miscellaneous Issues

    The FAA has also received a number of comments raising other
significant issues. These comments, and the associated responses, are
discussed below.
Statutory Authority
    ATA stated that this rule exceeds the FAA's statutory authority and
that this rule cannot be promulgated pursuant to the authority
delegated to the FAA in 49 U.S.C. 44701(a)(5) because this rule does
not increase aviation safety or national security.
    As the NPRM indicated, the authority for this rulemaking stems from
49 U.S.C. 44701(a)(5), which requires the Administrator to promulgate
``regulations and minimum standards for other practices, methods, and
procedure the Administrator finds necessary for safety in air commerce
and national security.'' Subsection 44701(a)(5) ``grants the FAA `broad
authority to regulate civil aviation.''' Gorman v. National Transp.
Safety Bd., 558 F.3d 580, 590 (DC Cir. 2009) (quoting Ass'n of Flight
Attendants-CWA v. Chao, 493 F.3d 155, 157 (D.C. Cir. 2007)).\94\
---------------------------------------------------------------------------

    \94\ See Drake v. Laboratory Corp. of America Holdings, 458 F.3d
48, 56 (2d Cir. 2006) (stating that ``Congress granted the FAA broad
authority over aviation safety''); Kraley v. National Transp. Safety
Bd., 165 F.3d 27 (6th Cir. 1998) (unpublished opinion) (stating that
``Congress vested the Administrator of the FAA with broad power to
prescribe regulations, standards, and procedures relating to
aviation safety'').
---------------------------------------------------------------------------

    Here, the FAA finds that this rulemaking is necessary for safety in
air commerce. As discussed in other portions of this preamble, the
existing flight, duty, and rest regulations permit flightcrew members
to accumulate unsafe amounts of fatigue. This unsafe accumulation of
fatigue undermines aviation safety by increasing the risk of an
accident.\95\ This rulemaking addresses this issue by imposing limits
that will ensure that flightcrew members' fatigue stays within safety-
acceptable bounds. This will decrease the risk of an aviation accident,
and thus, this rulemaking will increase safety in air commerce. Because
this rulemaking will increase safety in air commerce, it is authorized
by 49 U.S.C. 44701(a)(5).
---------------------------------------------------------------------------

    \95\ See, e.g., Goode, supra note 17, at 311 (stating that 16-
hour unaugmented FDPs, which are permissible under the existing
regulations, result in an accident rate that is over five times
higher than the accident rate for shorter FDPs).
---------------------------------------------------------------------------

    As the NPRM also notes, additional authority for this rulemaking
stems from 49 U.S.C. 44701(a)(4). Subsection 44701(a)(4) requires the
Administrator to promulgate ``regulations in the interest of safety for
the maximum hours or periods of service of airmen and other employees
of air carriers.'' This rule reduces the fatigue experienced by
flightcrew members during flight by limiting the maximum FDP and
flight-time hours of airmen and other covered

employees of air carriers. Because this reduction in fatigue will
increase aviation safety, the flight, duty, and rest limits that make
up this rule are also authorized by subsection 44701(a)(4).
Constitutional Due Process
    UPS argued that this rule is unconstitutional because its
provisions substantially impair the collective bargaining agreement
between UPS and IPA. Although UPS conceded that the Contracts Clause is
not applicable to the federal government, UPS argued that ``similar
principles apply [to the federal government] under the Due Process
Clause.'' UPS concluded that this rule violates the Fifth Amendment's
Due Process Clause because, UPS alleged, there is no justification for
the contractual impairment imposed by this rule.
    The FAA agrees with UPS that the Contracts Clause is not applicable
to actions, such as this rulemaking, that are undertaken by the federal
government. Pension Ben. Guar. Corp. v. R.A. Gray & Co., 467 U.S. 717,
732 n.8 (1984). With regard to UPS' Fifth Amendment argument, the
Supreme Court has explicitly rejected the premise that the Fifth
Amendment's Due Process Clause is ``coextensive'' with the Contracts
Clause. Id. at 733. The Court emphasized that ``to the extent that
recent decisions of the Court have addressed the issue, we have
contrasted the limitations imposed on States by the Contract Clause
with the less searching standards imposed on economic legislation by
the Due Process Clauses.'' Id. Thus, under the standard set out by the
Supreme Court, a federal regulation does not offend the Due Process
Clause so long as that regulation is not ``arbitrary and irrational.''
Id.
    This rule is neither arbitrary nor irrational. While the FAA
initiated this rulemaking by establishing an ARC, we subsequently
received a Congressional directive, which came about because the
existing flight, duty, and rest regulations allowed flightcrew members
to accumulate dangerous levels of fatigue. To address this issue and
keep flightcrew-member fatigue within reasonable bounds, this rule: (1)
Limits daily FDP and flight-time hours based on a flightcrew member's
circadian rhythm, (2) sets minimum rest requirements, and (3)
encourages fatigue-mitigating measures such as split-duty rest and
augmentation. This rule also contains a number of other provisions,
which are based on specific fatigue and operational concerns and which
are discussed in other parts of this preamble. In addition, each of the
proposed provisions in this rule was amended, where possible, to
respond to the specific concerns raised by the commenters. Because each
provision in this rule has been carefully calibrated to mitigate
flightcrew-member fatigue while providing air carriers with as much
scheduling flexibility as possible, this rule is neither arbitrary nor
irrational. Accordingly, this rule does not violate the Fifth
Amendment's Due Process Clause.
Administrative Procedure Act
    ATA and a number of other industry commenters criticized the
timetable used for this rulemaking. These commenters stated that the
ARC for this rulemaking met on an unreasonably compressed schedule that
did not provide it with sufficient time to carefully consider the
pertinent issues and come to a consensus as to the proper resolution of
those issues. CAA stated that, rather than provide the ARC with
sufficient time to come up with a comprehensive set of recommendations,
``the overwhelming majority of all regulatory activity has focused
exclusively on reductions to the current limitations on hours of duty
and flight time limits without ever determining whether such hours of
service considerations are in fact the underlying cause of any
fatigue.'' CAA concluded that ``[a]s a result, the proposals contained
in the NPRM are, on the whole, simply designed to reduce the flightcrew
hours of service.''
    The industry commenters also stated that the NPRM was an
``incomplete and ambiguous document'' that did not provide them with
sufficient detail to make meaningful comments. A number of commenters
argued that the regulatory impact analysis used to develop the NPRM
omitted important information, and thus, precluded the commenters from
providing meaningful critique of this analysis.
    CAA also stated that the FAA should have waited to publish an NPRM
until the National Research Council's Committee on the Effects of
Commuting on Pilot Fatigue provided a final report on the fatigue-
related effects of pilot commuting. CAA stated that commuting is the
primary cause of pilot fatigue, and that an understanding of pilot
commuting is a necessary part of any flight, duty, and rest rule.
    In addition, the industry commenters argued that the FAA did not
provide them with sufficient time to evaluate the NPRM and submit their
comments. They stated that the FAA unreasonably refused their requests
to extend the 60-day comment period and provided responses to their
numerous clarification questions with less than 30 days left in the
comment period. Some commenters also stated that the FAA did not
release a technical document that was used in the regulatory evaluation
until there were only 23 days left in the comment period. The
commenters pointed out that when the FAA conducted a similar rulemaking
in 1995, it extended the comment period, citing ``the scope and
complexity of the proposal.'' The commenters also stated that an
analogous rulemaking conducted by the Department of Transportation
Federal Motor Carrier Safety Administration to establish rules on hours
of service for commercial motor vehicles permitted an extension of the
comment period for that rulemaking. The industry commenters stated that
the existence of the ARC was not a sufficient justification for the
short comment period because this rule includes a number of provisions
that the ARC never considered.
    RAA suggested that the FAA issue a supplemental NPRM instead of
finalizing this rule. RAA emphasized that the FAA received a large
number of comments asking that substantial changes be made to this
rule, and to account for the number and breadth of the comments, the
FAA should issue a supplemental NPRM setting out its proposed
resolution to the issues raised by the comments.
    In response to the above comments, the FAA notes that while it
began this rulemaking by establishing an ARC, we subsequently received
a Congressional directive contained in the Airline Safety and Federal
Aviation Extension Act (ASFAEA). Section 212 of ASFAEA required the FAA
to issue new flight, duty, and rest regulations. This section, in
subsection 212(a)(3), set a deadline of 180 days for the FAA to publish
an NPRM and 1 year for the FAA to issue a final rule.
    Under normal circumstances, the FAA has broad discretion to extend
the timeframe for some parts of the rulemaking process. As the above
commenters correctly pointed out, the FAA has used this discretion in
the past to extend the timeframe for parts of other rulemakings.
However, in this case, the FAA has recognized that implicit within the
shortened statutory deadline that Congress set for completing this
rulemaking was a presumption against extending the timeframe for any
part of this rulemaking.
    The FAA limited the ARC's schedule to approximately six weeks. The
ARC actually met on a weekly basis for at least 2 days per week. The
FAA recognizes the tremendous amount of effort expended by the ARC
members

during this time. At the six-week point, the FAA found that the ARC had
achieved its goal of highlighting issues for the FAA to consider as
part of the FAA's subsequent rulemaking deliberations. Because most of
these issues elicited strong divergent opinions from the labor and
industry ARC members and because these divergent opinions could not be
reasonably reconciled, the FAA concluded that extending the ARC's
timeframe would not result in a consensus set of ARC recommendations.
    The FAA disagrees with CAA's assertion that the ARC's timeframe was
not extended because the FAA wanted to design a rule that ``reduce[s]
the flightcrew hours of service.'' While some parts of this rule reduce
flightcrew members' hours of service, other parts increase those hours
in a way that is consistent with safety considerations. Thus, for
example, this rule increases the existing 8-hour unaugmented daily
flight-time limit to 9 hours for periods of peak circadian alertness.
    Turning to the length of the comment period that was used for this
rulemaking, the FAA chose not to extend this rule's comment period due
to the detailed comments that it received and the implicit statutory
presumption against extensions in this rulemaking. At the end of the
60-day comment period, the FAA examined the comments that were
submitted in response to the NPRM, and determined it was unlikely that
an extension of the comment period would have a significant effect on
comment quality. During the 60-day comment period, thousands of
comments were submitted in response to this rulemaking, and many of
those comments contained lengthy comprehensive analyses of every single
part of the NPRM, as well as a critique of the regulatory evaluation. A
number of commenters hired their own experts to provide detailed
substantive reports on the NPRM, and these reports were submitted to
the FAA during the 60-day comment period. Based on the comprehensive
and detailed comments received during the 60-day comment period, the
FAA determined that it had received sufficient information to proceed
with this rulemaking. In light of this fact and the need to comply with
the statutory deadline for this rulemaking, the FAA chose not to extend
the comment period.
    The FAA also notes that, as the NPRM pointed out, the FAA has a
policy of considering comments that are ``filed after the comment
period has closed if it is possible to do so without incurring expense
or delay.'' 75 FR 55884. Thus, for example, as part of its
consideration of augmented FDPs, the FAA took into account Continental
and ALPA's comments about ULR flights, even though those comments were
filed four months after the comment period closed. Because the FAA has
a very liberal late-filed-comments policy, if the affected parties had
important new comments that they wanted to file after the 60-day
comment period closed, those parties had ample opportunity to file
their comments after the closure of the comment period.
    As the commenters pointed out, about halfway through the comment
period, the FAA provided answers to clarifying questions that the
commenters submitted, as well as a technical report that was referred
to by the regulatory evaluation. While this information, which was
provided with over 23 days left in the comment period, was important,
it was not a central component of the NPRM. Moreover, the commenters
appear to have fully incorporated this information into their filed
comments, as the comments contained a comprehensive analysis of both
the clarifying answers and the regulatory evaluation.
    Turning to the sufficiency of the NPRM, the FAA finds that the NPRM
provided enough detail for the commenters to provide the FAA with
meaningful comments. The NPRM set out the regulatory provisions that
the FAA proposed for the new flight, duty, and rest regulations, and
the NPRM also explained the rationale for each of those provisions.
After reading the NPRM and the accompanying regulatory evaluation, the
affected parties provided the FAA with thousands of comments, many of
which analyzed in detail every provision of the NPRM and provided a
critique of the FAA's rationale for each of those provisions. While
many of the commenters disagreed with parts of the NPRM, most of them
appear to have had a clear understanding of the NPRM. The affected
parties also submitted very detailed critiques of the regulatory
evaluation that accompanied the NPRM which showed an understanding of
the regulatory evaluation.
    As a result of the comprehensive and detailed analyses that were
submitted by the commenters, the FAA incorporated many of the
commenters' suggestions into the final rule and the final Regulatory
Impact Analysis. This process improved the final rule and accomplished
the requirements of the Administrative Procedure Act.
    Turning to CAA's comment, the FAA notes that since commencing this
rulemaking activity, the National Research Council has completed its
report. The authors of the report independently determined that it is
premature to initiate rulemaking related to commuting. See The Effects
of Commuting on Pilot Fatigue, National Research Council, July 6,
2011.\96\ While pilot commuting is an important fatigue-related issue,
this rulemaking does not foreclose the FAA from conducting a rulemaking
in the future to address pilot commuting issues should better and more
complete information of the risks posed by commuting and methods to
alleviate that risk become available.
---------------------------------------------------------------------------

    \96\ In addition to reviewing the possibility of regulating
pilot commuting, the National Research Council determined that
fatigue mitigation needed to take into account multiple factors,
including the duration of work periods within a single day and over
time; the time of day that work occurs; duration of sleep on work
days and non-work days, the volume and intensity of the work; and
the different vulnerabilities of individuals to these factors (among
others). This assessment is consistent with the FAA's assessment of
fatigue risk.
---------------------------------------------------------------------------

    The FAA has also decided not to issue a supplemental NPRM as part
of this rulemaking. As discussed above, the FAA received numerous
thorough and high-quality comments in response to the original NPRM.
Many of the comments have been incorporated into the final rule. We
have made no changes that were not either originally contemplated in
the NPRM or a logical outgrowth of that document.
Information Quality Act and OMB Bulletin M-05-03
    ATA asserted that the NPRM violated the Information Quality Act
(IQA), as applied by the Department of Transportation's (DOT)
Information Dissemination Quality Guidelines (Guidelines).\97\ ATA
argued that the Guidelines require FAA rulemakings to meet defined
standards of quality, objectivity, utility and integrity. ATA then
argued that ``[d]espite the IQA's clear mandate and DOT's guidance,
however, the present NPRM contains no accurate, clear, objective and
unbiased information supporting the FAA's proposed overhaul of the
existing flightcrew member flight and duty time limitations and rest
requirements.'' ATA stated that the scientific information used to
support the provisions of the NPRM could not meet the standards set out
in the Guidelines because it was not validated in the aviation context.
CAA added that the FAA's failure to provide additional regulatory-
impact information requested by CAA was also a violation of the IQA.
UPS argued that the scientific information used in this rulemaking
violated OMB Bulleting M-

05-03 because it was not subjected to peer review.
---------------------------------------------------------------------------

    \97\ Citing 67 FR 61719 (Oct. 1, 2002).
---------------------------------------------------------------------------

    The DOT Guidelines state that, in the context of a rulemaking, the
method by which an agency should correct alleged violations of the IQA
is by responding to the pertinent public comments in the preamble to
the final rule. Guidelines section VIII. In this case, a number of
commenters argued that certain provisions of the NPRM were not
supported by scientific information. A significant number of scientific
studies were referenced in the NPRM. However, in response to the
commenters' scientific concerns, the FAA has included either additional
scientific information supporting the studies cited in the NPRM or an
explanation for why the scientific information and operational
experience cited in the NPRM is sufficient to justify the pertinent
regulatory provision.
    The FAA notes that, while some of the studies used in the final
rule have not been validated in the aviation context, the major
provisions of this rule are based on uncontroversial scientific
findings that apply to all human beings. As the NPRM pointed out, sleep
science, while still evolving, is clear in several important respects:

    Most people need eight hours of sleep to function effectively,
most people find it more difficult to sleep during the day than
during the night, resulting in greater fatigue if working at night;
the longer one has been awake and the longer one spends on task, the
greater the likelihood of fatigue; and fatigue leads to an increased
risk of making a mistake.

75 FR 55857. These uncontroversial scientific findings form the basis
for almost all of the major provisions in this rule. The FAA has
concluded that, even though some of these findings were not based on
aviation data, flightcrew members have the same fatigue concerns as
other human beings, and as such, there is no reason to believe that
these findings would not apply to flightcrew members.
    However, in the process of considering the comments, the FAA found
that some of the provisions of the NPRM, such as portions of the
proposed fitness-for-duty section and the cumulative duty-period limit,
were not justified by scientific studies and operational experience.
Consequently, these provisions were removed from the final rule.
Because, in this preamble, the FAA responded to comments questioning
the scientific basis for the NPRM and removed regulatory provisions
that could not be justified through scientific findings or operational
experience, this rule does not violate the IQA and the DOT
Guidelines.\98\
---------------------------------------------------------------------------

    \98\ The FAA also notes that the DOT Guidelines are simply the
``policy views of DOT.'' Guidelines section III. These Guidelines
``are not intended to be, and should not be construed as, legally
binding regulations or mandates.'' Id.
---------------------------------------------------------------------------

    Turning to OMB Bulletin M-05-03, this Bulletin requires that ``[t]o
the extent permitted by law, each agency shall conduct a peer review on
all influential scientific information that the agency intends to
disseminate.'' OMB Bulletin M-05-03, section II(1). The studies cited
in this document were not conducted on behalf of the FAA and only
generally note trends in sleep science. As noted earlier in this
document, sleep science does not now, and likely never will, reach the
level of certainty that would allow an agency to make public policy
decisions based solely on scientific studies. While the science is
informative, final decisions will necessarily be based on a balancing
of interests in the real world rather than on rigid adherence to
scientific studies. This rule complies with this Bulletin because
almost all of the scientific information cited in this preamble comes
from peer-reviewed scientific journals. Two notable exceptions are the
TNO Report and the SAFTE/FAST modeling that was used in parts of this
rule. However, the FAA has determined that both the TNO Report and the
SAFTE/FAST model have been evaluated sufficiently to provide useful
information to the agency in making policy decisions on how best to
balance the needs of carriers to maximize their operations while still
providing sufficient and meaningful rest opportunities to mitigate the
risk of fatigue to those operations. The TNO Report's findings were
reviewed by the Scientific Review Board of the Netherlands Organization
for Applied Scientific Research, Department of Behavioral and Social
Sciences (which complies with ISO 9001:2000 certification standards)
and the review board of the Directorate General Transport and Aviation
of the Netherlands Ministry of Transport. Turning to the SAFTE/FAST
model, as the NPRM pointed out ``[t]his model is widely used, with
approximately 14 major carriers and sixteen governmental agencies
world-wide having used the model to evaluate fatigue in aviation and
other industrial settings.'' 75 FR 55867 n.35. The NPRM also noted that
a copy of the technical report evaluating this model has been placed on
the docket, and, in addition, the NPRM cited a number of studies that
either evaluated or utilized the SAFTE/FAST model. See id. n.34.
Executive Order 12866
    A number of industry commenters stated that this rulemaking does
not comply with Executive Order 12866 because: (1) Its benefits do not
justify its costs, (2) it is not based on scientific information, (3)
the FAA has not assessed alternatives, and (4) the rule is unduly
burdensome.
    The commenters stated that the FAA admitted that sleep science has
not been validated in the aviation context and portions of this rule,
such as cumulative duty-period limits and lower unaugmented FDP limits
for additional flight segments, are not based on scientific evidence.
ATA and UPS argued that this rule also violated Section 212 of the
Airline Safety and Federal Aviation Extension Act because, according to
ATA and UPS, this rule is not based on the best science.
    ATA and RAA criticized the FAA's approach to this rulemaking. RAA
stated that the ARC members whose recommendations were used in this
rulemaking have considerable operational experience, and that the less
conservative, air carrier ARC recommendations were based on this
experience and did not undermine safety. RAA added that some of the
specific limits set out in this rule could have been increased due to
the fact that this rule contains significant safety oversight
provisions.
    The industry commenters also stated that the FAA has not considered
alternatives to this rule because its ``one-size fits all'' proposal
does not take into account ``the unique needs of individual carriers or
types of operations.'' ATA stated that this rule is unduly burdensome
because the NPRM ``improperly treats passenger, cargo, short-haul,
long-haul, domestic, and international carriers and operations the same
despite their crucial, differing operational demands and crew
scheduling requirements.''
    NACA asserted that the FAA never considered the alternative
proposals submitted by supplemental air carriers. NACA added that the
FAA never explained why it excluded part 135 operators from this rule,
but did not exclude other small business entities such as supplemental
air carriers. ATA stated that the FAA did not carefully consider the
impact that maintaining the status quo would have on small business
entities, and that this violated the Regulatory Flexibility Act.
    Executive Order 12866 requires, among other things, that a federal
agency: (1) ``propose or adopt a

regulation only upon a reasoned determination that the benefits of the
intended regulation justify its costs;'' (2) base its decision on the
best available scientific information; (3) consider alternatives to the
proposed regulation; and (4) ``tailor its regulations to impose the
least burden on society, including individuals, businesses of differing
sizes.''
    The FAA has determined that the benefits of this rule justify its
costs. A detailed discussion explaining the FAA's basis for this
determination is contained in the Regulatory Impact Analysis. The FAA
has also used the best available scientific information as the basis
for this rule. As discussed in the preceding section, most of the
provisions in this rule are supported by the latest peer-reviewed
scientific studies. While some of these peer-reviewed studies have not
been validated in the aviation context, as discussed above, the major
provisions of this rule are based on uncontroversial scientific
findings that apply to all human beings.
    The FAA acknowledges that the proposed cumulative duty-period
limits were largely unnecessary, which is why they have been removed
from the final rule. With regard to lower unaugmented FDP limits for
additional flight segments, as the pertinent section of this preamble
points out, a number of scientific studies support the premise that an
increase in the number of flight segments leads to an increase in
flightcrew member fatigue.\99\ The FAA also acknowledges that certain
provisions of the NPRM were unduly conservative, and these provisions
have been amended in response to concerns expressed by the commenters.
For example, the unaugmented FDP limits, which were based on the most
conservative ARC recommendation, have been amended in accordance with
higher FDP-limit alternatives that were proposed by industry
commenters.
---------------------------------------------------------------------------

    \99\ See supra notes 36-38.
---------------------------------------------------------------------------

    The FAA has also considered alternatives to the provisions set out
in the NPRM. As the NPRM stated, the FAA has considered the alternative
of maintaining the status quo, but rejected that alternative because
the status quo subjects society to an ``unacceptably high aviation
accident risk.'' 75 FR 55882. For example, as discussed in the
Applicability section of this preamble, some of the FDPs permitted by
the existing regulations can result in a five-fold increase to accident
risk.
    The FAA has also considered the alternative of differentiating
between different types of part 121 operations. As a result, the FAA
has decided to make the provisions of this rule voluntary for all-cargo
operations, as subjecting all-cargo operations to the same mandatory
flight, duty, and rest regulations as passenger operations would result
in costs that far outweigh the commensurate societal benefit.
    The FAA also considered differentiating between the different types
of part 121 passenger operations. However, the FAA ultimately decided
against this approach because, as discussed in the Applicability
section, the factors that lead to fatigue are universal and, unlike
all-cargo operations, imposing this rule on passenger operations is
cost-justified. A flightcrew member who is working on a 16-hour
unaugmented FDP will feel the same level of fatigue regardless of the
type of operation that he or she is participating in. Accordingly, this
rule uniformly regulates the universal fatigue factors in passenger
operations regardless of the specific part 121 passenger operation that
is involved.
    The FAA has also considered the impact that this rule would have on
supplemental passenger operations, and it has incorporated a number of
suggestions from carriers who conduct supplemental operations and
organizations that represent those carriers, into the final rule. The
reason that the FAA excluded part 135 businesses regardless of size,
but did not exclude air carriers who conduct supplemental operations
from this rule, is that the air carriers who conduct supplemental
operations operate under part 121 which contains more stringent safety
standards than those found in part 135. Pursuant to the Regulatory
Flexibility Act, the FAA also considered the impact of this rule on
small businesses, and the pertinent discussion can be found below.
    Throughout this rulemaking, the FAA has attempted to impose the
least possible burden on air carriers, consistent with the need to
improve safety. As many commenters pointed out, some provisions of this
rule are complex because the FAA has consistently decided against
imposing across-the-board flight, duty, and rest limitations, which
would have been more stringent than necessary. Instead, this rule
imposes stringent limits in safety-critical areas, such as the WOCL,
and less stringent limits in other areas, such as unaugmented FDPs that
begin in the morning.
    The FAA also notes that the uniform approach used in this
rulemaking provides additional scheduling flexibility to air carriers.
For example, because this rule does not differentiate between
international and domestic flights (aside from acclimation and time-
zone-crossing issues), this rule permits augmentation on domestic
flights, which existing regulations do not allow. In addition, because
this rule does not differentiate between supplemental passenger
operations and other part 121 passenger flights, this rule does not
require supplemental passenger operations to provide flightcrew members
with additional compensatory rest that is mandated by existing
regulations. Accordingly, this rule complies with Executive Order 12866
because it: (1) Has benefits that justify its costs, (2) is based on
the best available scientific information, (3) was finalized after the
FAA considered a number of other alternatives, and (4) is tailored to
impose the least burden on society.
Voluntary Consensus
    ATA argued that this rule should have used a voluntary consensus
standard instead of a government-unique standard. ATA stated that OMB
Circular A-119 requires agencies to use voluntary standards whenever
possible, and that the short time span given to the ARC was not
sufficient for the ARC to address the complex issues present in this
rulemaking.
    As an initial matter, the FAA notes that there is no voluntary
consensus standard for the issues addressed by this rulemaking. The FAA
disagrees with ATA's assertion that OMB Circular A-119 requires the FAA
to use a voluntary consensus standard in this rulemaking. Subsection
6(c) of OMB Circular A-119 states that:

    This policy does not preempt or restrict agencies' authorities
and responsibilities to make regulatory decisions authorized by
statute. Such regulatory authorities and responsibilities include
determining the level of acceptable risk; setting the level of
protection; and balancing risk, cost, and availability of technology
in establishing regulatory standards.

    This rulemaking consists of the FAA exercising its regulatory
responsibility and establishing the acceptable level of fatigue-related
risk, setting the appropriate level of protection from fatigue, and
balancing the risks of fatigue with the costs that will be borne by air
carriers as a result of this rule. Because subsection 6(c) of OMB
Circular A-119 excludes this type of agency action from the circular's
requirements, OMB Circular A-119 does not preempt or restrict the FAA's
statutory authority to conduct this rulemaking. See id.

Public Interest
    ATA stated that this rule would also harm the public interest by:
(1) Reducing the number of U.S. jobs by hurting the competitive nature
of the U.S. air carrier industry; (2) harm the U.S. economy by imposing
excessive costs on air carriers; (3) disrupt air travel and waste
passengers' air time as a result of additional cancelled and delayed
flights; and (4) disrupt critical air deliveries.
    As discussed above, this rule does not hurt the competitive nature
of the U.S. air carrier industry. This rule simply reflects a different
conceptual approach that the FAA utilized in light of its significant
operational experience with daily flight-time limits. With regard to
the remaining concerns expressed in the comments, as discussed in the
Regulatory Impact Analysis, the costs that are imposed by this rule are
justified by the associated benefits of reducing the risk that
passengers will be involved in an accident.
Two-Year Effective Date
    RAA also stated that a two-year effective date for this rule may be
too short given the magnitude of the changes being proposed, and the
complex process, development, training, and system programming, testing
and implementation that would be required to effect those changes
cannot be properly accomplished in such a time period. RAA emphasized
that the changes being proposed by this rule ``go to the very heart''
of an airline's operations.
    The FAA understands that this rule imposes complex new requirements
that go to the heart of an airline's operations. That is why this rule
provides air carriers with two years to make changes to their existing
flight schedules and operations and if necessary, to address any labor
agreement issues. The FAA has determined that two years is a
substantial period of time, and that a longer effective date is
unwarranted in light of the fact that, as discussed above, existing
regulations allow flightcrew members in passenger operations to
accumulate unsafe amounts of fatigue.
Federal Motor Carrier Safety Administration Hours of Service Rulemaking
    FMCSA has been engaged in long-term rulemaking related to its hours
of service regulations for commercial truck drivers. Like the FAA,
FMCSA is working to address the universality of factors that lead to
fatigue. However, the FAA has taken a different approach in addressing
fatigue risk among pilots than FMCSA has with respect to commercial
truck drivers. This is because the two industries operate differently
both in terms of the likely number of days the affected individuals
work per month and the respective operating environments. For example,
pilots regularly cross multiple time zones in a very short period of
time--something that is simply not possible in other modes of
transportation. Additionally, pilots may work several days that are
very long, but then be off for an extended period of time, a practice
that naturally imposes a non-regulatory restorative rest opportunity.
Finally, the nature of commercial flying is such that under typical
conditions, the actual operation is likely to require intense
concentration primarily during take-offs and landings, with a constant,
but generally predictable level of concentration required for other
phases of flight.
    In contrast, commercial truck drivers face an environment where
they are required to share the highways with drivers who have not
received specialized training and are not subject to any regulatory
constraints that pilots are subject to. This environment could
logically lead to a regulatory approach with different fatigue
mitigators for daytime operations on congested highways, compared to
nighttime operations, where the roads are less crowded but the risk of
fatigue is greater.

IV. Regulatory Notices and Analyses

A. Regulatory Evaluation

    Changes to Federal regulations must undergo several economic
analyses. First, Executive Order 12866 and Executive Order 13563
directs that each Federal agency shall propose or adopt a regulation
only upon a reasoned determination that the benefits of the intended
regulation justify its costs. Second, the Regulatory Flexibility Act of
1980 (Pub. L. 96-354) requires agencies to analyze the economic impact
of regulatory changes on small entities. Third, the Trade Agreements
Act (Pub. L. 96-39) prohibits agencies from setting standards that
create unnecessary obstacles to the foreign commerce of the United
States. In developing U.S. standards, the Trade Agreements Act requires
agencies to consider international standards and, where appropriate,
that they be the basis of U.S. standards. Fourth, the Unfunded Mandates
Reform Act of 1995 (Pub. L. 104-4) requires agencies to prepare a
written assessment of the costs, benefits, and other effects of
proposed or final rules that include a Federal mandate likely to result
in the expenditure by State, local, or tribal governments, in the
aggregate, or by the private sector, of $100 million or more annually
(adjusted for inflation with base year of 1995). This portion of the
preamble summarizes the FAA's analysis of the economic impacts of this
proposed rule. The FAA suggests readers seeking greater detail read the
full regulatory impact analysis, a copy of which the agency has placed
in the docket for this rulemaking.
    In conducting these analyses, the FAA has determined that this
final rule: (1) Has benefits that justify its costs even though under
the base case scenario the quantified costs are greater than the
quantified benefits, (2) is not an economically ``significant
regulatory action'' as defined in section 3(f) of Executive Order
12866, (3) is ``significant'' as defined in DOT's Regulatory Policies
and Procedures; (4) will have a significant economic impact on a
substantial number of small entities; (5) will not create unnecessary
obstacles to the foreign commerce of the United States; and (6) will
not impose an unfunded mandate on state, local, or tribal governments,
or on the private sector by exceeding the threshold identified above.
These analyses are summarized below.
Total Benefits and Costs Over a 10 Year Period
    We have analyzed the benefits and the costs associated with the
requirements contained in this Final Rule over a 10 year period. We
provide a range of estimates for our quantitative benefits. Our base
estimate is $376 million ($247 million present value at 7% and $311
million present value at 3%) and our high case estimate is $716 million
($470 million present value at 7% and $593 million at 3%). The total
estimated cost of the Final Rule is $390 million ($297 million present
value at 7% and $338 million at 3%).
    Additionally, the FAA believes there are substantial, non-
quantified health benefits associated with the final rule. The agency
has not evaluated the effect of fatigue on the overall, long-term
health of the pilot community because those health impacts are unlikely
to have an impact on aviation safety in a quantifiable manner. However,
as ALPA noted in one of its meetings with OMB under its E.O. 12866
procedures, the societal cost associated with long-term fatigued-
related health problems can be substantial.\100\ Decreasing these costs

represents a societal benefit. While we have not quantified these
potential benefits, they may well exceed the projected costs of the
rule when added to our base case estimate.
---------------------------------------------------------------------------

    \100\ See OMB submission from ALPA dated October 28, 2011.
http://www.whitehouse.gov/omb/oira_2120_meetings/.
---------------------------------------------------------------------------

    The actual benefits of the final rule will depend upon the type and
size of accident that the rule averts. We have provided a base case
estimate, based on historical accidents and the regulatory structure in
place at the time those accidents occurred, and a high estimate, based
on a projection of future accidents that broadly reflect the historical
accident profile. Neither estimate assumes a catastrophic accident
aboard a large passenger aircraft. This is because no large passenger
aircraft were represented in the historical accident analysis rather
than because there is no fatigue-related risk to those operations. We
note that preventing a single catastrophic accident with 61 people on
board would cause this rule to be cost beneficial.

------------------------------------------------------------------------
                      Total benefits over 10 years
-------------------------------------------------------------------------
                                     Nominal      PV at 7%     PV at 3%
             Estimate               (millions)   (millions)   (millions)
------------------------------------------------------------------------
Base.............................         $376         $247         $311
High.............................          716          470          593
------------------------------------------------------------------------

                        Total costs over 10 years
-------------------------------------------------------------------------
                                     Nominal      PV at 7%     PV at 3%
            Component               (millions)   (millions)   (millions)
------------------------------------------------------------------------
Flight Operations................         $236         $157         $191
Rest Facilities..................          138          129          134
Training.........................           16           11           13
                                  --------------------------------------
    Total........................          390          297          338
------------------------------------------------------------------------

Benefits of the Rule
    The benefit analysis first examines the nature of fatigue, followed
by its causes and how it relates to transportation. Second, it
summarizes some recent findings on fatigue and occupational
performance. Third, it looks at the magnitude of crew fatigue in Part
121 commercial aviation by briefly examining fatigue reports in the
context of this final rule. We then re-analyze the likely effectiveness
of the requirements contained in this final rule and the potential to
decrease these types of accidents in the future. The FAA projects a
likely number of preventable events that will occur in absence of this
final rule. Finally, the agency estimates the benefits that will be
derived from preventing such events and a range of benefits based upon
likely scenarios.
    Here the FAA provides a quantitative benefit estimate of
historical-based accidents (base case), and a high case of expected
benefits from future averted accidents once this rule is promulgated.
Generally our benefit analysis begins using past history as an
important reference from which to begin the benefit analysis. We
believe the base case benefit estimate, which is based solely on the
outcome of past accidents, may be low because today passenger load
factors and aircraft size are already greater than they were in the
past decade. We also note that this estimate may not fully take into
account changes in regulatory requirements that postdate those
accidents and that may mitigate the projected risk. As such, our base
case estimate represents a snapshot of risk.
    Airplane accidents are somewhat random both in terms of airplane
size and the number of people on board. For these reasons, projections
of future fatalities may be based on future risk exposure, and our
projections are typically based on expected distributions around the
mean. Our typical scenario incorporates increasing airplane size,
expected load factors, and a breakeven analysis. However, our
evaluation of the historical accidents showed a disproportionate risk
among smaller, regional carriers. Accordingly, as we discuss below, the
FAA has decided to base its high case estimate on preventing an
accident in a regional jet airplane.
    In response to comments, we have reduced the analysis period from
the 20 years provided in the proposed regulatory analysis to 10 years
here. We received comments disputing the use of a 20 year time frame
for accidents stating the accident rate has declined over time. While
noting the wide range of operations over the last 20 years, we
shortened the accident history to the last ten years. A reduction in
the length of the sample period introduces other problems, most
importantly with less time there are fewer observations. Observations
are important, as the nature of aviation accidents is that while they
are rare events, very often these accidents result in severe, high
consequences.
    The FAA Office of Accident Investigation assessed the effectiveness
of this rule to prevent the 6 fatigue-related accidents which occurred
on passenger-carrying aircraft in a recent ten year period. This office
used the Commercial Aviation Safety Team (CAST) methodology to assign a
value to how effective the rule will be at preventing each accident. On
average, we expect this rule would have been 52.5 percent effective in
preventing the types of accidents had it been in effect over the last
10 years.
Base Case Estimate
    The base case estimate only looks at the historical events as a
specific reference point. In this estimate the exact number of
fatalities for each past event is multiplied by the relative rule
effectiveness score to obtain the historical number of deaths that
would have been averted with the requirements contained in this final
rule, had this rule been in effect at the time. The base case estimate
supposes roughly six deaths will be averted annually. Multiplying six
annual averted deaths by the $6.2 million value of statistical life
equals $37 million annually. In addition, had the requirements been in
place at the time of these historical accidents, $2 million in hull
damage for each accident would have been averted, which equals $6
million for ten years or $0.6 million annually. When summed over the
ten year period of analysis, the base case estimate is $376 million
($247 million present value at 7% and $311 million present value at
3%).

High Case Estimate
    Because airplane accidents are relatively rare they are not
necessarily representative of actual risk, especially with regard to
airplane size and the number of people on-board. In addition, future
conditions will be different than they were when the accident occurred.
Thus, the base case represents a snapshot of the risk that fatigue
introduces in the overall operating environment. It considers neither
the forecasted increase in load factors nor the larger aircraft types.
The future preventable events that this rule addresses will not exactly
mirror the past events because the airplane types, utilization, and
seating capacity have changed.
    To quantify the expected benefits in the high case scenario, we
narrowed the analysis to three of the six historic accidents which were
catastrophic (all on board died). In this case the expected number of
preventable catastrophic accidents equals the three accidents
multiplied by the 52.5 percent effectiveness rate. Thus over a ten-year
time period the expected number of preventable accidents is 1.575.
Using the Poisson distribution there is roughly a 20 percent chance for
no accident; however, there is also a 50 percent probability of two or
more accidents.
    While the 20 year accident history has a broader range of
catastrophic accidents, in the shorter ten year historical period all
the three catastrophic accidents were on regional airplanes. We
recognize that as regional airplanes are smaller than the `typical'
passenger jet, assuming all future accidents would be on a regional jet
may understate the relative risk across the fleet of aircraft affected
by this rule. It does, however, represent historical accidents and may
be somewhat representative actual future risk, since the mainline
carriers typically have collective bargaining agreements that are
already largely reflective of the requirements of this rule.\101\
---------------------------------------------------------------------------

    \101\ It is unusual that collective bargaining agreements would
closely mirror regulatory requirements. However, flight and duty
limitations are unique because they address both safety
considerations, which are regulatory in nature, and lifestyle
considerations, which are properly addressed in collective
bargaining agreements. Because of the impact of collective
bargaining agreements on the number of hours that pilots work, those
agreements were considered by the FAA in calculating both the costs
and benefits of this rule.
---------------------------------------------------------------------------

    The average size airplane in the forecast period is a B737/A320
with an expected number of passengers and crew of 123 given a
forecasted 142 seat airplane and a load factor of 83 percent.\102\ Even
though there was a (relatively large) B757 passenger airplane accident
in the 20 year history, if one looks at the past 10 years as truly
representative of risk, the preventable accident would likely be on a
regional airplane.
---------------------------------------------------------------------------

    \102\ Table 6, FAA Aerospace Forecasts Fiscal Years 2011.
---------------------------------------------------------------------------

    For the high case the FAA backed away from a benefit outcome based
on mean fleet, flight hours, and occupant numbers because ultimately we
were persuaded there was information which could not be ignored by the
three regional passenger accidents occurring without a mainline
passenger accident. For this reason, we selected an 88 seat regional
jet (like an ERJ-175) to be the representative airplane for the high
case. This size airplane is also consistent with the fact that regional
operators are expected to fly somewhat larger airplanes in the future.
    The expected benefit from this high case follows a simple
methodology for estimating and then valuing the expected number of
occupants in a prevented accident. With a total of 0.3 accidents per
year over the ten year period multiplied by the 52.5 percent
effectiveness rate, the analysis assumes 0.1575 average accidents per
year. The estimated occupant value for each averted accident equals the
average number of seats (88) multiplied by the load factor of 77% plus
4 crew members for a total of 72 averted fatalities. Each of these
prevented fatalities is multiplied by a $6.2 million value of
statistical life. The expected value of a preventable accident equals
the sum of the averted fatalities at $446.4 million added to the value
of the airplane hull loss ($8.15 million replacement value), for a
prevented accident benefit of $454.6 million.\103\ Over a ten year
period the value of preventing the expected 1.575 accidents equals
approximately $716 million ($470 million present value at 7% and $593
million present value at 3%).
---------------------------------------------------------------------------

    \103\ In contrast, the value of an averted all-cargo fatal
accident would range between $20.35 million (loss of hull and 2
crewmembers) and $32.55 million (loss of hull and 4 crewmembers).
---------------------------------------------------------------------------

Cost of the Rule
    The total estimated cost of the Final Rule is $390 million ($297
million at 7% present value and $338 million at 3% present value). The
FAA classified costs into three main components and estimated the costs
for each component. Data was obtained from various industry sources;
the sources of the data used in cost estimation are explained in each
section. Flight operations cost accounts for 53 percent of the total
present value cost of the rule. Rest facilities and fatigue training
accounts for approximately 43 percent and 4 percent, respectively. Each
of the main cost components is explained in-depth in the Regulatory
Evaluation.

----------------------------------------------------------------------------------------------------------------
                                                                   Nominal cost      PV at 7%        PV at 3%
                         Cost component                             (millions)      (millions)      (millions)
----------------------------------------------------------------------------------------------------------------
Flight Operations...............................................            $236            $157            $191
Rest Facilities.................................................             138             129             134
Training........................................................              16              11              13
                                                                 -----------------------------------------------
    Total.......................................................             390             297             338
----------------------------------------------------------------------------------------------------------------

Alternatives Considered--The alternatives are shown in the section
``Final Regulatory Flexibility Analysis''

B. Final Regulatory Flexibility Analysis

    The Regulatory Flexibility Act of 1980 (RFA) establishes ``as a
principle of regulatory issuance that agencies shall endeavor,
consistent with the objective of the rule and of applicable statutes,
to fit regulatory and informational requirements to the scale of the
business, organizations, and governmental jurisdictions subject to
regulation.'' To achieve that principle, the RFA requires agencies to
solicit and consider flexible regulatory proposals and to explain the
rationale for their actions. The RFA covers a wide-range of small
entities, including small businesses, not-for-profit organizations and
small governmental jurisdictions.
    Agencies must perform a review to determine whether a proposed or
final rule would have a significant economic impact on a substantial
number of small entities. If the determination is that it would, the
agency must prepare a

regulatory flexibility analysis as described in the RFA.
    The FAA believes that this final rule will have a significant
economic impact on a substantial number of small entities and therefore
has performed final regulatory flexibility analysis in accordance with
section 604(a)(1)-(5), highlighted below:
    1. A succinct statement of the need for, and objectives of, the
rule.
    2. A summary of the significant issues raised by the public
comments in response to the IRFA, a summary of the assessment of the
agency of such issues, and a statement of any changes made in the
proposed rule as a result of such comments.
    3. A description and an estimate of the number of small entities to
which the rule will apply or an explanation of why no such estimate is
available.
    4. A description of the projected reporting, recordkeeping, and
other compliance requirements of the rule, including an estimate of the
classes of small entities that will be subject to the requirement and
the types of professional skills necessary for preparation of the
report or record.
    5. A description of the steps the agency has taken to minimize the
significant adverse economic impact on small entities consistent with
the stated objectives of applicable statutes, including a statement of
the factual, policy, and legal reasons for selecting the alternative
adopted in the final rule and why each of the other significant
alternatives to the rule considered by the agency were rejected. We
address each requirement.
1. A Succinct Statement of the Need for, and Objectives of, the Rule
    This final rule amends the FAA's existing flight, duty and rest
regulations applicable to certificate holders and their flightcrew
members operating under 14 CFR Part 121. The rule recognizes the
universality of factors that lead to fatigue in most individuals.
Fatigue threatens aviation safety because it increases the risk of
pilot error that could lead to an accident. The new requirements
eliminate the current distinctions between domestic, flag and
supplemental operations as they apply to passenger operations. The rule
provides different requirements based on the time of day, whether an
individual is acclimated to a new time zone, and the likelihood of
being able to sleep under different circumstances. The objective of the
proposed rule is to increase the margin of safety for passengers
traveling on U.S. part 121 air carrier flights. Specifically, the FAA
wants to decrease diminished flight crew performance associated with
fatigue or lack of alertness brought on by the duty requirements for
flightcrew members.
2. A Summary of the Significant Issues Raised by the Public Comments in
Response to the IRFA, a Summary of the Assessment of the Agency of Such
Issues, and a Statement of Any Changes Made in the Proposed Rule as a
Result of Such Comments
    NAA, NJASAP, Southern Air, Lynden Air Cargo, NACA and U.S. Chamber
of Commerce stated that RFA of the proposed rule failed to address the
full burden to be borne by small entities, such as nonscheduled air
carriers, and that the FAA did not follow RFA requirements in
addressing alternative means of compliance that would lessen the
economic burden on small entities.
    Since the NPRM, the FAA has made substantial changes to the duty
and rest requirements that will significantly reduce the cost to small
entities.
3. A Description and an Estimate of the Number of Small Entities to
Which the Rule Will Apply or an Explanation of Why No Such Estimate Is
Available
    The final rule applies to all certificate holders operating under
part 121 who conduct passenger operations. There are 67 such operators,
of which 55 operators have fewer than 1,500 employees.
4. A Description of the Projected Reporting, Recordkeeping, and Other
Compliance Requirements of the Rule, Including an Estimate of the
Classes of Small Entities That Will Be Subject to the Requirement and
the Types of Professional Skills Necessary for Preparation of the
Report or Record
    As described in the Paperwork Reduction Analysis, there are
additional compliance requirements for reporting and recordkeeping.
5. A Description of the Steps the Agency Has Taken To Minimize the
Significant Adverse Economic Impact on Small Entities Consistent With
the Stated Objectives of Applicable Statutes, Including a Statement of
the Factual, Policy, and Legal Reasons for Selecting the Alternative
Adopted in the Final Rule and Why Each of the Other Significant
Alternatives to the Rule Considered by the Agency was Rejected.
    Current crew schedules vary by operator, labor contract, and size
of pilot pools. As such, the impact to small entity operators will
vary. The agency understands that many smaller operators have maximized
their pilot time in the cockpit and may have little flexibility with
potential new flight and duty regulations and we have taken steps to
minimize the economic impact on small entities. In response to several
comments from small entities, the FAA has made significant changes from
the proposal in this final rule which will minimize the economic impact
on small entities. In addition, the FAA has largely removed schedule
reliability from this rule. The FAA has instead adopted provisions that
limit extensions of the FDP and requires reporting of FDP extensions
and activities that were not otherwise permitted by the provisions of
Sec.  117.11, Sec.  117.19 and Sec.  117.29 in the Final Rule. Under
this amendment, costs to airline carriers are limited to reporting
exceptional activities by sending electronic mails to the FAA.

Alternative--Require Four Hours' Mid-duty Rest To Work on Give
Consecutive Nighttime FDPs

    This final rule reduces (to two hours) the amount of mid-duty rest
necessary to work on five consecutive nighttime FDPs. The FAA rejected
the higher mid-duty rest requirement proposed in the NPRM because of
the potential negative impact on small businesses and the safety risks
that are discussed in the pertinent part of the preamble.

Alternative--Different Limitations on Supplemental Passenger Operations

    The FAA has considered imposing different limitations on small
supplemental passenger operations but has rejected this alternative.
The FAA has decided to impose the same FDP limits on passenger
supplemental operations as other part 121 operations. While there are
relatively few supplemental passenger operations, the FAA has
determined that these pilots should be as rested as those in scheduled
service since the numbers of passengers onboard the aircraft are
similar to those on board an aircraft operating as a scheduled service.
Furthermore, a significant number of these operations involve the
transport of troops. The United States government believes these
passengers should not be exposed to a level of risk different from if
they were transported via a scheduled service operation.

Alternative--Exclude/Exempt Supplemental Passenger Operations

    The FAA has also considered excluding supplemental passenger
operations from this rule but rejected this alternative for the same
reasons that it rejected the alternative of imposing different
limitations on supplemental passenger operations. In addition, the FAA
has noted that its decision to include supplemental operations in this

rule was not specifically targeted at small businesses because many
large air carriers also have supplemental authority.

Alternative--Require All-Cargo Operators To Comply With the Final Rule

    The FAA has also considered requiring all-cargo operators to comply
with part 117. However, the FAA decided to make compliance with this
part voluntary for all-cargo operations because their compliance costs
significantly exceed the quantified safety benefits.

C. International Trade Impact Assessment

    A number of industry commenters argued that finalizing the NPRM as
written would undermine the ability of U.S. air carriers to compete
with foreign air carriers. These commenters stated that 49 U.S.C.
40101(a)(15) and (e)(1) require the Secretary of Transportation to
ensure that U.S. air carriers compete on equal terms with foreign
carriers. The commenters then pointed out that this rule contains
provisions, such as daily flight-time limits, that are not a part of
analogous foreign regulations, and that these provisions hurt the
international competitive position of U.S. air carriers who are subject
to this rule.
    The industry commenters added that the imposition of daily flight-
time limits, which are not contained in foreign aviation regulations,
creates an unnecessary obstacle to the foreign commerce of the United
States, and thus violates the Trade Agreements Act of 1979 (TAA)
(codified at 19 U.S.C. sections 2531-2533). The commenters also argued
that by imposing daily flight-time limits, the FAA did not properly
consider other international standards, and thus violated the TAA, OMB
Circular A-119, and Executive Order 12866, all of which require the FAA
to consider international standards.
    The Trade Agreements Act of 1979 (Pub. L. 96-39), as amended by the
Uruguay Round Agreements Act (Pub. L. 103-465), prohibits Federal
agencies from establishing standards or engaging in related activities
that create unnecessary obstacles to the foreign commerce of the United
States. Pursuant to these Acts, the establishment of standards is not
considered an unnecessary obstacle to the foreign commerce of the
United States, so long as the standard has a legitimate domestic
objective, such the protection of safety, and does not operate in a
manner that excludes imports that meet this objective. The statute also
requires consideration of international standards and, where
appropriate, that they be the basis for U.S. standards.\104\ The FAA
has assessed the potential effect of this final rule and determined
that it would enhance safety and is not considered an unnecessary
obstacle to trade.
---------------------------------------------------------------------------

    \104\ As discussed in the International Compatibility section,
there are no ``international standards'' to consider.
---------------------------------------------------------------------------

    The flight-time limits in this rule do not undermine the
international competitive position of U.S. air carriers. While this
rule sets daily flight-time limits that many foreign aviation rules do
not contain, the additional fatigue mitigation created by the daily
flight-time limits permits the FAA to set less stringent requirements
in other parts of this rule. For example, this rule only requires a 10-
hour rest period between FDPs instead of the 12-hour rest period
required by many foreign flight, duty, and rest regulations. This rule
also permits 14-hour FDPs for periods of peak circadian alertness while
some foreign regulations, such as EU Rules, Subpart Q, only permit FDPs
that do not exceed 13 hours.\105\
---------------------------------------------------------------------------

    \105\ See EU Rules, Subpart Q, OPS 1.1100, section 1.3 and OPS
1.1110, section 1.1.
---------------------------------------------------------------------------

    As the above examples demonstrate, the imposition of daily flight-
time limits is simply the result of a different conceptual approach
that was utilized by the FAA. The FAA chose this approach because it
has significant operational experience administering daily flight-time
limits, and the FAA chose to employ this experience to better calibrate
the specific provisions of this rule. This difference in approach does
not undermine the competitive position of U.S. air carriers because the
imposition of daily flight-time limits permitted the FAA to make other
parts of this rule less stringent than the analogous provisions of
foreign flight, duty, and rest regulations.

D. Unfunded Mandates Assessment

    Title II of the Unfunded Mandates Reform Act of 1995 (Pub. L. 104-
4) requires each Federal agency to prepare a written statement
assessing the effects of any Federal mandate in a proposed or final
agency rule that may result in an expenditure of $100 million or more
(in 1995 dollars) in any one year by State, local, and tribal
governments, in the aggregate, or by the private sector; such a mandate
is deemed to be a ``significant regulatory action.'' The FAA currently
uses an inflation-adjusted value of $143.1 million in lieu of $100
million. This final rule does not contain such a mandate; therefore,
the requirements of Title II do not apply.

E. Paperwork Reduction Act

    The paperwork burden comprises of five areas, fatigue risk
management system Sec.  117.7, fatigue training Sec.  117.9, flight
time limitation Sec.  117.11, and flight duty period extension
reporting Sec.  117.19 and Emergency and government sponsored
operations Sec.  117.29. The following analyses were conducted under
Paperwork Reduction Act of 1995 (44 U.S.C. 3501).

(1) PRA analysis for reporting fatigue risk management system (FRMS)
Sec.  117.7 provision

    The final rule will allow each air carrier to develop a Fatigue
Risk Management System (FRMS) if it wishes. FRMS is a voluntary program
in the final rule. It will result in an annual recordkeeping and
reporting burden if some of industry carriers eventually adopt the
system so that they need to report the related activities to the FAA.
Total FRMS annualized paperwork burden is determined by the numbers of
FRMS to be developed and FRMS reporting cost per responders. FAA
estimated that FRMS will incur the paperwork burden about $14,950
annually, $149,500 nominal cost for 10 years or $99,186 present value
at 7%. FAA took steps to arrive the estimate as follows.
    a. Number of respondents (air carriers): the FAA estimated
approximately 20 carriers or respondents;
    b. Estimated time of paperwork: about 11.5 hours per air carrier
and 230 hours in total for data collection, annual FRMS record-keeping
and reporting required by the FAA;
    c. Average hourly wage rate of a FRMS information respondent
(manager level): $65 per hour for reporting and analyzing FRMS data;
    d. FRMS paperwork hour estimation: total 230 hours (11.5 hours x 20
estimated carriers);