[Federal Register Volume 77, Number 2 (Wednesday, January 4, 2012)]
[Rules and Regulations]
[Pages 330-403]
[FR Doc No: 2011-33078]

Vol. 77

Wednesday,

No. 2

January 4, 2012

Part II

Department of Transportation

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Federal Aviation Administration

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14 CFR Parts 117, 119, and 121

Flightcrew Member Duty and Rest Requirements; Final Rule

Federal Register / Vol. 77 , No. 2 / Wednesday, January 4, 2012 /
Rules and Regulations

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Parts 117, 119, and 121

[Docket No. FAA-2009-1093; Amdt. Nos. 117-1, 119-16, 121-357]
RIN 2120-AJ58

Flightcrew Member Duty and Rest Requirements

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: This rule amends the FAA's existing flight, duty and rest
regulations applicable to certificate holders and their flightcrew
members operating under the domestic, flag, and supplemental operations
rules. The rule recognizes the universality of factors that lead to
fatigue in most individuals and regulates these factors to ensure that
flightcrew members in passenger operations do not accumulate dangerous
amounts of fatigue. Fatigue threatens aviation safety because it
increases the risk of pilot error that could lead to an accident. This
risk is heightened in passenger operations because of the additional
number of potentially impacted individuals. The new requirements
eliminate the current distinctions between domestic, flag and
supplemental 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.

DATES: Effective January 14, 2014.

ADDRESSES: For information on where to obtain copies of rulemaking
documents and other information related to this final rule, see ``How
To Obtain Additional Information'' in the SUPPLEMENTARY INFORMATION
section of this document.

FOR FURTHER INFORMATION CONTACT: For technical issues: Dale E. Roberts,
Air Transportation Division (AFS-200), Flight Standards Service,
Federal Aviation Administration, 800 Independence Avenue SW.,
Washington, DC 20591; telephone<PHONE_NUMBER>; email:
<EMAIL_ADDRESS>For legal issues: Rebecca MacPherson, Office of
the Chief Counsel, Regulations Division (AGC-200), 800 Independence
Avenue SW., Washington, DC 20591; telephone<PHONE_NUMBER>; email:
<EMAIL_ADDRESS>
SUPPLEMENTARY INFORMATION:

Authority for This Rulemaking

    The FAA's authority to issue rules on aviation safety is found in
Title 49 of the United States Code. This rulemaking is promulgated
under the authority described in 49 U.S.C. 44701(a)(5), which requires
the Administrator to promulgate regulations and minimum safety
standards for other practices, methods, and procedures necessary for
safety in air commerce and national security. This rulemaking is also
promulgated under the authority described in 49 U.S.C. 44701(a)(4),
which 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.

Table of Contents

I. Overview of Final Rule
II. Background
    A. Statement of the Problem
    B. National Transportation Safety Board (NTSB) Recommendations
    C. Flight and Duty Time Limitations and Rest Requirements
Aviation Rulemaking Committee
    D. Congressional Mandate
    E. Notice of Proposed Rulemaking
III. Discussion of Public Comments and Final Rule
    A. Applicability
    B. Definitions
    C. Fitness for Duty
    D. Fatigue Education and Training
    E. Fatigue Risk Management System
    F. Flight Duty Period--Unaugmented
    G. Flight Time Limitations
    H. Flight Duty Period--Augmented
    I. Schedule Reliability
    J. Extensions of Flight Duty Periods
    K. Split Duty
    L. Consecutive Nights
    M. Reserve
    N. Cumulative Limits
    O. Rest
    P. Deadhead Transportation
    Q. Emergency and Government Sponsored Operations
    R. Miscellaneous Issues
IV. Regulatory Notices and Analyses
    A. Regulatory Evaluation
    B. Final Regulatory Flexibility Analysis
    C. International Trade Impact Assessment
    D. Unfunded Mandates Assessment
    E. Paperwork Reduction Act
    F. International Compatibility
    G. Environmental Analysis
V. Executive Order Determinations
    A. Executive Order 12866
    B. Executive Order 13132, Federalism
    C. Executive Order 13211, Regulations That Significantly Affect
Energy Supply, Distribution, or Use
VI. How To Obtain Additional Information
    A. Rulemaking Documents
    B. Comments Submitted to the Docket
    C. Small Business Regulatory Enforcement Fairness Act

I. Overview of Final Rule

    The FAA is issuing this final rule to address the risk that fatigue
poses to passenger operations conducted under 14 CFR part 121. Part 121
applies to the majority of flights flown by the American public. As
such, changes to the existing flight, duty and rest rules in part 121
will directly affect the flying public. This rule applies to all part
121 passenger operations, including traditional scheduled service and
large charter operations. The FAA has removed the existing distinctions
between domestic, supplemental and flag passenger operations because
the factors leading to fatigue are universal and addressing the risk to
the flying public should be consistent across the different types of
operations.
    This final rule addresses fatigue risk in several ways. The
underlying philosophy of the rule is that no single element of the rule
mitigates the risk of fatigue to an acceptable level; rather, the FAA
has adopted a system approach, whereby both the carrier and the pilot
accept responsibility for mitigating fatigue. The carrier provides an
environment that permits sufficient sleep and recovery periods, and the
crewmembers take advantage of that environment. Both parties must meet
their respective responsibilities in order to adequately protect the
flying public.
    The final rule recognizes the natural circadian rhythms experienced
by most people that causes them to be naturally more tired at night
than during the day. Under the final rule, flightcrew members will be
able to work longer hours during the day than during the night.
Significant changes in time zones, a situation unique to aviation, are
accounted for to reduce the risk to the flying public posed by
``jetlag''.
    The FAA has decided against adopting various provisions proposed in
the NPRM. The final rule does not apply to all-cargo operations,
although those carriers have the ability to fly under the new rules if
they so choose. The proposal that carriers meet certain schedule
reliability requirements has been dropped, as has the proposed
requirement that carriers evaluate flightcrew members for fatigue. The
FAA has determined that these provisions were either overly costly or
impractical to implement.

1. Fitness for Duty

    This rule places a joint responsibility on the certificate holder
and each flightcrew member. In order for the flightcrew member to
report for an FDP properly rested, the certificate holder must provide
the flightcrew member

with a meaningful rest opportunity that will allow the flightcrew
member to get the proper amount of sleep. Likewise, the flightcrew
member bears the responsibility of actually sleeping during the rest
opportunity provided by the certificate holder instead of using that
time to do other things. The consequence of a flightcrew member
reporting for duty without being properly rested is that he or she is
prohibited from beginning or continuing an FDP until he or she is
properly rested.

2. Fatigue Education and Training

    Part 121 air carriers are currently statutorily-required to
annually provide, as part of their Fatigue Risk Management Plan,
fatigue-related education and training to increase the trainees'
awareness of: (1) Fatigue; (2) ``the effects of fatigue on pilots;''
and (3) ``fatigue countermeasures.'' Today's rule adopts the same
standard of training as required by the statute. In addition, today's
rule adopts a mandatory update of the carriers' education and training
program every two years, as part of the update to their FRMP. Both of
these regulatory provisions merely place the existing statutory
requirements in the new flight and duty regulations for the ease and
convenience of the regulated parties and the FAA.

3. Fatigue Risk Management System

    The FAA proposed a Fatigue Risk Management System (FRMS) as an
alternative regulatory approach to provide a means of monitoring and
mitigating fatigue. Under an FRMS, a certificate holder develops
processes that manage and mitigate fatigue and meet an equivalent level
of safety. The FAA is adopting that proposal largely as proposed. The
FAA has also decided to extend the voluntary FRMS program to all-cargo
operations, which are not required to operate under part 117. Under the
FRMS provisions that this rule adds to subparts Q, R, and S of part
121, an all-cargo operator that does not wish to operate under part 117
can nevertheless utilize an FRMS as long as it has the pertinent FAA
approval.

4. Unaugmented Operations

    One of the regulatory concepts that this rule introduces is the
restriction on flightcrew members' maximum Flight Duty Period (FDP). In
creating a maximum FDP limit, the FAA attempted to address three
concerns. First, flightcrew members' circadian rhythms needed to be
addressed because studies have shown that flightcrew members who fly
during their window of circadian low (WOCL) can experience severe
performance degradation. Second, the amount of time spent at work
needed to be taken into consideration because longer shifts increase
fatigue. Third, the number of flight segments in a duty period needed
to be taken into account because flying more segments requires more
takeoffs and landings, which are both the most task-intensive and the
most safety-critical stages of flight. To address these concerns, the
FAA is adopting as part of the regulatory text a table limiting maximum
FDP based on the time of day and the number of segments flown during
the FDP period. Under today's rule an FDP begins when a flightcrew
member is required to report for duty that includes a flight and ends
when the aircraft is parked after the last flight and there is no plan
for further aircraft movement by the same flightcrew member. The
maximum FDP limit is reduced during nighttime hours to account for
being awake during the WOCL; when an FDP period consists of multiple
flight segments in order to account for the additional time on task;
and if a flightcrew member is unacclimated to account for the fact that
the unacclimated flightcrew member's circadian rhythm is not in sync
with the theater in which he or she is operating. Actual time at the
controls (flight time) is limited to 8 or 9 hours, depending on the
time of day that the FDP commences.

5. Augmented Operations

    In order to accommodate common operational practices, the final
rule allows longer duty periods in instances where the carrier provides
additional crew and adequate on-board rest facilities. The extended
FDPs are laid out in a table and provide maximum credit when an
operator employs a 4-man crew and provides the highest quality on-board
rest facility.

6. Extensions of Flight Duty Periods

    This rule sets forth the limits on the number of FDPs that may be
extended; implements reporting requirements for affected FDPs; and
distinguishes extended FDPs due to unforeseen operational circumstances
that occur prior to takeoff from those unforeseen operational
circumstances that arise after takeoff. The FAA agrees that an
extension must be based on exceeding the maximum FDP permitted in the
regulatory tables rather than on the times that the air carrier had
originally intended for an FDP, which may be considerably less than the
tables allow. It is unreasonable to limit extensions on FDPs that are
less than what the certificate holder can legally schedule. In
addition, there is a 30-minute buffer attached to each FDP to provide
certificate holders with the flexibility to deal with delays that are
minimal.

7. Split Duty

    Split duty rest breaks provide carriers with nighttime operations
with additional flexibility. Typically split duty rest would benefit
carriers who conduct late night and early morning operations where the
flightcrew members would typically be afforded some opportunity to
sleep, but would not receive a legal rest period. Under today's rule
split duty rest must be at least 3 hours long and must be scheduled in
advance. The actual split duty rest breaks may not be shorter than the
scheduled split duty rest breaks. The rationale for this is that
flightcrew members must, at the beginning of their FDP, evaluate their
ability to safely complete their entire assigned FDP. In order to do
so, they must not only know the length of the FDP, but any scheduled
split duty rest breaks that they will receive during the FDP.

8. Consecutive Night Operations

    In formulating this rule, the FAA was particularly concerned about
cumulative fatigue caused by repeatedly flying at night. Modeling shows
substantially deteriorating performance after the third consecutive
nighttime FDP for flightcrew members who worked nightshifts during
their WOCL and obtained sleep during the day. However, if a sleep
opportunity is provided during each nighttime FDP, that sleep
opportunity may sustain flightcrew member performance for five
consecutive nights. Based on modeling results, the FAA has determined
that a 2-hour nighttime sleep opportunity each night improves pilot
performance sufficient to allow up to 5 nights of consecutive nighttime
operations.

9. Reserve

    The FAA has decided to rely on the expertise represented in the ARC
to address the issue of reserve duty. The adopted regulatory provisions
addressing reserve and unaugmented operations provide that the total
number of hours a flightcrew member may spend in a flight duty period
and reserve availability period may not exceed 16 hours or the maximum
applicable flight duty period table plus four hours, whichever is less.
This will allow most FDPs to be accommodated by a flightcrew member on
short-call reserve. This rule adopts the proposal that limits the
short-call reserve availability period, in which the

flightcrew member is not called to report to work, to 14 hours.

10. Cumulative Limits

    The FAA is adopting cumulative limits for 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
restrictions on cumulative flight time, which can easily be tracked by
scheduling programs currently in use throughout the industry. The FAA
has decided to eliminate the cumulative duty-period limits, which
should greatly simplify compliance with this section.

11. Rest

    Carriers will be required to provide their crew with a 10-hour rest
opportunity prior to commencing a duty period that includes flying.
While the 10-hour rest period may include the amount of time it takes
to get to or from a flightcrew member's house or hotel room, the actual
amount of time required for a sleep opportunity may not be reduced
below 8 hours. In addition, the length of continuous time off during a
7-day period has been extended from 24 hours under the existing rules
to 30 hours. Additional time off is required for individuals whose
internal clock may be off because of flipping back and forth between
different time zones.

12. Emergency and Government Sponsored Operations

    This rulemaking also addresses 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 an emergency
situation to moving armed troops for the U.S. military, conducting
humanitarian relief, repatriation, Air Mobility Command (AMC), and
State Department missions. 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. 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. This authority is issued on a case-by-
case basis during an emergency situation as determined by the
Administrator. 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.
Costs and Benefits
    We have analyzed the benefits and the costs associated with the
requirements contained in this final rule. We provide a range of
estimates for our quantitative benefits. Our base case estimate is $376
million ($247 million present value at 7% and $311 million at 3%) and
our high case estimate is $716 million ($470 million present value at
7% and $593 million at 3%). The FAA believes there are also not-
quantified benefits to the rule that, when added to the base case
estimate, make the rule cost beneficial. The total estimated cost of
the final rule is $390 million ($297 million present value at 7% and
$338 million at 3%).

                      Summary Over a 10 Year Period
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                        Total quantified benefits
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                                     Nominal      PV at 7%     PV at 3%
             Estimate               (millions)   (millions)   (millions)
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Base.............................         $376         $247         $311
High.............................          716          470          593
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                         Total quantified costs
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                                     Nominal      PV at 7%     PV at 3%
            Component               (millions)   (millions)   (millions)
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Flight Operations................         $236         $157         $191
Rest Facilities..................          138          129          134
Training.........................           16           11           13
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    Total........................          390          297          338
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    The FAA has made significant changes to the final rule since the
NPRM. The training requirement has been substantially reduced because
the FAA has determined that pilots are already receiving the requisite
training as part of the statutorily required Fatigue Risk Management
Plans. The FAA also has removed all-cargo operations from the
applicability section of the new part 117 because their compliance
costs significantly exceed the quantified societal benefits.\1\ All-
cargo carriers may choose to comply with the new part 117 but are not
required to do so. Since the carrier would decide voluntarily to comply
with the new requirements, those costs are not attributed to the costs
of this rule. The costs associated with the rest facilities occur in
the two years after the rule is published. The other costs of the rule
and the benefits are then estimated over the next ten years.
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    \1\ The projected cost for all-cargo operations is $306 million
($214 million present value at 7% and $252 million at 3%). The
projected benefit of avoiding one fatal all-cargo accident ranges
between $20.35 million and $32.55 million, depending on the number
of crewmembers on board the aircraft.
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II. Background

    On September 14, 2010, the FAA published a Flightcrew Member Duty
and Rest Requirements notice of proposed rulemaking (NPRM) setting out
proposed flight, duty, and rest regulations intended to limit
flightcrew member fatigue in part 121 operations. These proposed
regulations applied to all operations conducted pursuant to part 121,
and the regulations would

have imposed, among other things, the following limits/requirements:
(1) A requirement that a flightcrew member must notify the certificate
holder (air carrier) when he or she is not fit for duty and that a
certificate holder must also independently evaluate its flightcrew
members for fitness for duty; (2) a limit on daily flight duty period
(FDP) and flight-time hours that varies depending on the time of day
that the FDP begins; (3) cumulative limits on FDPs, flight times, and
duty periods; (4) a schedule reliability requirement, which stated that
a certificate holder's scheduled FDPs must be at least 95% consistent
with actual FDPs; (5) a requirement that a flightcrew member be
provided with at least 9 consecutive hours of rest between FDPs, as
measured from the time the flightcrew member reaches a suitable
accommodation; and (6) credit for employing fatigue-mitigating measures
such as split-duty rest and augmentation.
    The FAA received over 8,000 comments in response to the NPRM. In
response to the comments, the FAA has made a number of changes to the
regulatory provisions proposed in the NPRM. These changes include the
following:
     The mandatory provisions of the NPRM do not apply to all-
cargo operations. Instead, this rule permits all-cargo operations to
voluntarily opt into the new flight, duty, and rest limitations imposed
by this rule.
     Certificate holders are no longer required to
independently verify whether flightcrew members are fit for duty.
     Most of the daily FDP limits have been increased to
provide certificate holders with more scheduling flexibility. One of
the daily flight-time limits has been decreased to address safety
considerations.
     The cumulative duty-period limit has been removed from
this rule.
     The schedule-reliability requirement has been largely
removed from the final rule. The remaining parts of the schedule-
reliability process have been changed to only apply to instances in
which a flightcrew member exceeds the FDP and/or flight-time limits
imposed by this rule.
     The flightcrew member must now be provided with 10 hours
of rest between FDP periods, but that rest is measured from the time
that the flightcrew member is released from duty. The rest must provide
for an 8-hour sleep opportunity.
     The amount of credit provided for split-duty rest and
augmentation has been increased, and changes to the final rule make
these credits easier to obtain.
    The changes listed above are just some of the amendments that were
made to the NPRM in response to the comments. The Discussion of Public
Comments and Final Rule section of this preamble contains a discussion
of the changes that were made to the NPRM in response to issues raised
by the commenters.

A. Statement of the Problem

    Fatigue is characterized by a general lack of alertness and
degradation in mental and physical performance. Fatigue manifests in
the aviation context not only when pilots fall asleep in the cockpit in
flight, but perhaps more importantly, when they are insufficiently
alert during take-off and landing. Reported fatigue-related events have
included procedural errors, unstable approaches, lining up with the
wrong runway, and landing without clearances.
    There are three types of fatigue: Transient, cumulative, and
circadian. Transient fatigue is acute fatigue brought on by extreme
sleep restriction or extended hours awake within 1 or 2 days.
Cumulative fatigue is fatigue brought on by repeated mild sleep
restriction or extended hours awake across a series of days. Circadian
fatigue refers to the reduced performance during nighttime hours,
particularly during an individual's WOCL (typically between 2 a.m. and
6 a.m.).
    Common symptoms of fatigue include:
     Measurable reduction in speed and accuracy of performance,
     Lapses of attention and vigilance,
     Delayed reactions,
     Impaired logical reasoning and decision-making, including
a reduced ability to assess risk or appreciate consequences of actions,
     Reduced situational awareness, and
     Low motivation to perform optional activities.
    A variety of factors contribute to whether an individual
experiences fatigue as well as the severity of that fatigue. The major
factors affecting fatigue include:
     Time of day. Fatigue is, in part, a function of circadian
rhythms. All other factors being equal, fatigue is most likely, and,
when present, most severe, between the hours of 2 a.m. and 6 a.m.
     Amount of recent sleep. If a person has had significantly
less than 8 hours of sleep in the past 24 hours, he or she is more
likely to be fatigued.
     Time awake. A person who has been continually awake for a
long period of time since his or her last major sleep period is more
likely to be fatigued.
     Cumulative sleep debt. For the average person, cumulative
sleep debt is the difference between the amount of sleep a person has
received over the past several days, and the amount of sleep he or she
would have received with 8 hours of sleep a night.
     Time on task. The longer a person has continuously been
doing a job without a break, the more likely he or she is to be
fatigued.
     Individual variation. Individuals respond to fatigue
factors differently and may become fatigued at different times, and to
different degrees of severity, under the same circumstances.
    Scientific research and experimentation have consistently
demonstrated that adequate sleep sustains performance. For most people,
8 hours of sleep in each 24-hour period sustains performance
indefinitely. Sleep opportunities during the WOCL are preferable
because sleep that occurs during the WOCL provides the most
recuperative value. Within limits, shortened periods of nighttime sleep
may be nearly as beneficial as a consolidated sleep period when
augmented by additional sleep periods, such as naps before evening
departures, during flights with augmented flightcrews, and during
layovers. Sleep should not be fragmented with interruptions. In
addition, environmental conditions, such as temperature, noise, and
turbulence, impact how beneficial sleep is and how performance is
restored.
    When a person has accumulated a sleep debt, recovery sleep is
necessary to fully restore the person's ``sleep reservoir.'' Recovery
sleep should include at least one physiological night, that is, one
sleep period during nighttime hours in the time zone in which the
individual is acclimated. The average person requires in excess of 9
hours of sleep a night to recover from a sleep debt. \2\
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    \2\ Recovery sleep does not require additional sleep equal to
the cumulative sleep debt; that is, an 8-hour sleep debt does not
require 8 additional hours of sleep.
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    Several aviation-specific work schedule factors \3\ can affect
sleep and subsequent alertness. These include early start times,
extended work periods, insufficient time off between work periods,
insufficient recovery time off between consecutive work periods, amount
of work time within a shift or duty period, number of consecutive work
periods, night work through one's window of circadian low, daytime
sleep

periods, and day-to-night or night-to-day transitions.
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    \3\ Rosekind MR. Managing work schedules: an alertness and
safety perspective. In: Kryger MH, Roth T, Dement WC, editors.
Principles and Practice of Sleep Medicine; 2005:682.
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    The FAA believes that its current regulations do not adequately
address the risk of fatigue. The impact of this risk is greater in
passenger operations due to the number of persons placed at risk.
Presently, flightcrew members are effectively allowed to work up to 16
hours a day (regardless of the time of day), with all of that time
spent on tasks directly related to aircraft operations. The regulatory
requirement for 9 hours of rest is regularly reduced, with flightcrew
members spending rest time traveling to or from hotels and being
provided with little to no time to decompress. Additionally,
certificate holders regularly exceed the allowable duty periods by
conducting flights under part 91 instead of part 121, where the
applicable flight, duty and rest requirements are housed. As the
National Transportation Safety Board repeatedly notes, the FAA's
regulations do not account for the impact of circadian rhythms on
alertness. The entire set of regulations is overly complicated, with a
different set of regulations for domestic operations, flag operations,
and supplemental operations. In addition, these regulations do not
consider other factors that can lead to varying degrees of fatigue.
Instead, each set of operational rules (i.e. those applicable to
domestic, flag, or supplemental operations) sets forth a singular
approach toward addressing fatigue, regardless of the operational
circumstances that may be more or less fatiguing.\4\
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    \4\ While several of the commenters have claimed that the NPRM
proposed a ``one-size-fits-all'' regulatory structure, the FAA
believes this suggestion is misleading. In the NPRM, and in the
final rule with regard to passenger-carrying operations, the FAA has
eliminated distinctions between domestic, flag, and supplemental
operations, but in all of these operations, the rule imposes
differing requirements based on the operating environment.
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B. National Transportation Safety Board (NTSB) Recommendations

    The NTSB has long been concerned about the effects of fatigue in
the aviation industry. The first aviation safety recommendations,
issued in 1972, involved human fatigue, and aviation safety
investigations continue to identify serious concerns about the effects
of fatigue, sleep, and circadian rhythm disruption. Currently, the
NTSB's list of Most Wanted Transportation Safety Improvements includes
safety recommendations regarding pilot fatigue. These recommendations
are based on two accident investigations and an NTSB safety study on
commuter airline safety.\5\
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    \5\ On February 2, 2010, the NTSB released a press release
summarizing the results of its investigation into the Colgan Air
crash of February 12, 2009, which resulted in the death of 50
people. The NTSB did not state that fatigue was causal factor to the
crash; however, it did recommend that the FAA take steps to address
pilot fatigue.
---------------------------------------------------------------------------

    In February 2006 the NTSB issued safety recommendations after a
BAE-J3201 operated under part 121 by Corporate Airlines struck trees on
final approach and crashed short of the runway at Kirksville Regional
Airport, Kirksville, Missouri. The captain, first officer, and 11 of
the 13 passengers died. The NTSB determined the probable cause of the
October 19, 2004 accident was the pilots' failure to follow established
procedures and properly conduct a non-precision instrument approach at
night in instrument meteorological conditions. The NTSB concluded that
fatigue likely contributed to the pilots' performance and decision-
making ability. This conclusion was based on the less than optimal
overnight rest time available to the pilots, the early report time for
duty, the number of flight legs, and the demanding conditions
encountered during the long duty day.
    As a result of the accident, the NTSB issued the following safety
recommendations related to flight and duty time limitations: (1) Modify
and simplify the flightcrew hours-of-service regulations to consider
factors such as length of duty day, starting time, workload, and other
factors shown by recent research, scientific evidence, and current
industry experience to affect crew alertness (recommendation No. A-06-
10); and (2) require all part 121 and part 135 certificate holders to
incorporate fatigue-related information similar to the information
being developed by the DOT Operator Fatigue Management Program into
initial and recurrent pilot training programs. The recommendation notes
that this training should address the detrimental effects of fatigue
and include strategies for avoiding fatigue and countering its effects
(recommendation No. A-06-10).
    The NTSB's list of Most Wanted Transportation Safety Improvements
also includes a safety recommendation on pilot fatigue and ferry
flights conducted under 14 CFR part 91. Three flightcrew members died
after a Douglas DC-8-63 operated by Air Transport International was
destroyed by ground impact and fire during an attempted three-engine
takeoff at Kansas City International Airport in Kansas City, Missouri.
The NTSB noted that the flightcrew conducted the flight as a
maintenance ferry flight under part 91 after a shortened rest break
following a demanding round trip flight to Europe that crossed multiple
time zones. The NTSB further noted that the international flight,
conducted under part 121, involved multiple legs flown at night
following daytime rest periods that caused the flightcrew to experience
circadian rhythm disruption. In addition, the NTSB found the captain's
last rest period before the accident was repeatedly interrupted by the
certificate holder.
    In issuing its 1995 recommendations, the NTSB stated that the
flight time limits and rest requirements under part 121 that applied to
the flightcrew before the ferry flight did not apply to the ferry
flight operated under part 91. As a result, the regulations permitted a
substantially reduced flightcrew rest period for the nonrevenue ferry
flight. As a result of the investigation, the NTSB reiterated earlier
recommendations to (1) finalize the review of current flight and duty
time limitations to ensure the limitations consider research findings
in fatigue and sleep issues and (2) prohibit certificate holders from
assigning a flightcrew to flights conducted under part 91 unless the
flightcrew met the flight and duty time limits under part 121 or other
applicable regulations (recommendation No. A-95-113).
    In addition to recommending a comprehensive approach to fatigue
with flight duty limits based on fatigue research, circadian rhythms,
and sleep and rest requirements, the NTSB has also stated that a
Fatigue Risk Management System (FRMS) may hold promise as an approach
to dealing with fatigue in the aviation environment. However, the NTSB
noted that it considers fatigue management plans to be a complement to,
not a substitute for, regulations to address fatigue.

C. Flight and Duty Time Limitations and Rest Requirements Aviation
Rulemaking Committee

    As part of this rulemaking action, the FAA chartered an aviation
rulemaking committee (ARC) on June 24, 2009. The FAA brought together
pilots, airlines, and scientific experts to collaborate and develop
options for an FAA-proposed rulemaking to help mitigate pilot fatigue.
The ARC provided a forum for the U.S. aviation community to discuss
current approaches to mitigate fatigue found in international standards
(e.g., the International Civil Aviation Organization (ICAO) standard,
the United Kingdom Civil Aviation Publication (CAP) 371, and the
European Aviation Safety Agency

Notice of Proposed Amendment). The ARC provided its report, a copy of
which is in this rulemaking docket, to the agency on September 9, 2009.

D. Congressional Mandate

    On August 1, 2010, the President signed the Airline Safety and
Federal Aviation Administration Extension Act of 2010 (Pub. L. 111-
216). Section 212 of Public Law 111-216 required ``the FAA
Administrator to issue regulations to limit the number of flight and
duty time hours allowed for pilots to address pilot fatigue.'' 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.

E. Notice of Proposed Rulemaking

    On September 14, 2010, the FAA published in the Federal Register
the Flightcrew Member Duty and Rest Requirements NPRM.\6\ The NPRM
proposed to amend the FAA's existing flight, duty, and rest regulations
applicable to certificate holders and their flightcrew members. The
proposal recognized the factors that lead to fatigue in most
individuals, and it proposed to regulate these factors to ensure that
flightcrew members do not accumulate dangerous amounts of fatigue.
Because the proposed rule addressed fatigue factors that apply
universally, the proposed requirements eliminated the existing
distinctions between domestic, flag and supplemental operations. The
proposal also provided 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.
---------------------------------------------------------------------------

    \6\ 75 FR 55852; September 14, 2010.
---------------------------------------------------------------------------

    The NPRM provided for a 60-day comment period, which ended on
November 15, 2010. Following publication of the NPRM, the FAA received
a number of requests to extend the comment period and to clarify
various sections of the preamble, regulatory text, and the Regulatory
Impact Analysis (RIA). In response, the agency published two actions in
the Federal Register.
    The first action was a ``Notice of procedures for submission of
clarifying questions.'' \7\ Persons asking for clarifications were
advised to file their questions to the rulemaking docket by October 15,
2010. The FAA said it would respond by October 22, 2010. On October 22,
2010, the agency filed two response documents to the rulemaking docket:
``Response to Clarifying Questions to the RIA'' and ``Response to
Clarifying Questions to the NPRM.''
---------------------------------------------------------------------------

    \7\ 75 FR 62486; October 12, 2010.
---------------------------------------------------------------------------

    The second action was a ``Response to requests for a comment period
extension.'' \8\ The FAA provided notice that the comment period would
not be extended. The agency's rationale for this decision is outlined
in the October 15, 2010 action.
---------------------------------------------------------------------------

    \8\ 75 FR 63424; October 15, 2010.
---------------------------------------------------------------------------

    The FAA received more than 8,000 comment submissions, containing
multiple comments on various sections of the preamble and the rule.
Many comment submissions also included specific recommendations for
changes and clarifications.

III. Discussion of Public Comments and Final Rule

A. Applicability

    In the NPRM, the FAA stated that fatigue factors are ``universal.''
\9\ The FAA noted that sleep science, while still evolving, was clear
in several important respects:
---------------------------------------------------------------------------

    \9\ 75 FR 55852, 55857 (Sep. 14, 2010).

    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.

Id. In light of its determination concerning the universal
applicability of factors underlying fatigue, the FAA proposed a single
set of flight, duty, and rest regulations that would regulate these
factors. The proposed regulations would have been applicable to all
part 121 domestic, flag, and supplemental operations. The proposed
regulations would also have applied to all part 91 flights conducted by
part 121 certificate holders, including flights, such as ferry flights,
that have historically been conducted under part 91. The NPRM also
stated that ``the part 135 community should expect to see an NPRM
addressing its operations that looks very similar to, if not exactly
like, the final rule the agency anticipates issuing as part of its
rulemaking initiative.'' Id. The comments received in response to the
proposed applicability of this rule and the corresponding FAA responses
are included below.
    The National Air Carrier Association (NACA) and a number of air
carriers operating non-scheduled flights objected to the proposed rule
applying to supplemental operations. These industry commenters stated
that non-scheduled operations require additional scheduling flexibility
because they are fundamentally different from scheduled operations. The
industry commenters stated that, unlike scheduled operations, non-
scheduled operations provide on-demand operations on behalf of private
and government consumers on a timetable that is determined by the
consumer. According to the industry commenters, non-scheduled carriers
do not have regularly-set schedules that they know months in advance,
but are instead called to fly with little advance notice, making it
more difficult to plan flightcrew member flight times and rest periods.
The industry commenters emphasized that this difficulty is exacerbated
by the fact that non-scheduled operations' flight times (especially
departure times) are controlled largely by the consumer and not the air
carrier.
    The non-scheduled industry commenters also asserted that non-
scheduled carriers serve remote, sometimes hostile locations, with no
established crew bases. Thus, they do not have the same extensive
infrastructure that scheduled operations have access to and must
deadhead flightcrew members into remote locations in order to be able
to swap out flightcrew members during an operation. These commenters
emphasized that the certificate holders running non-scheduled
operations are largely small businesses that will have difficulty
adjusting to the burdens imposed by this rule.
    Based on the differences between non-scheduled and scheduled
operations, the industry commenters stated that a ``one-size-fits-all''
approach does not work for non-scheduled operations. The industry
commenters stated that the existing regulations governing supplemental
operations have existed for over 60 years, and that changing these
regulations will adversely affect air security and national defense
missions conducted through the use of non-scheduled operations. The
commenters emphasized that the existing supplemental flight, duty, and
rest regulations ensure aviation safety by containing additional rest
requirements that are not a part of this rule. In conclusion, the
industry commenters suggested that the FAA either: (1) Retain the
existing flight, duty, and rest regulations governing supplemental
operations, and/or (2) adopt the alternative proposal put forward by
the industry commenters.
    In addition to the concerns expressed by non-scheduled air
carriers, the Cargo Airline Association (CAA) and a number of air
carriers operating all-cargo flights have also objected to the

proposed rule applying to supplemental operations. These industry
commenters asserted that, while a passenger-operation accident can
result in numerous fatalities, an all-cargo accident would consist
primarily of property damage.
    The commenters also stated that the cargo industry is composed of
both scheduled and on-demand operators, and that it specializes in
express delivery services. To effectuate these express delivery
services, some all-cargo carriers do not maintain U.S. domicile bases
and regularly operate long-haul flights and point-to-point operations
outside the United States, traveling across multiple time zones at all
hours of the day and night. The industry commenters also stated that
all-cargo carriers regularly operate around the world in all directions
with extended overseas routings, not with quick overnight turns at
foreign destinations. This results in a lower aircraft utilization rate
than domestic passenger operations. According to the industry
commenters, these types of nighttime and around-the-world operations
are the norm for all-cargo carriers.
    The all-cargo industry commenters added that, similar to non-
scheduled operations, some all-cargo operations also fly to remote,
undeveloped, and sometimes hostile locations. According to the industry
commenters, these types of operations are driven by the same
considerations as similar non-scheduled operations: (1) The schedule is
determined primarily by the customer, and (2) there is a lack of
infrastructure, which necessitates deadheading in flightcrew members.
The industry commenters emphasized that many all-cargo carriers
currently provide their flightcrew members with split duty rest while
cargo is being sorted at sorting facilities, and that the carriers have
invested millions of dollars in high-quality rest facilities. The
industry commenters also stated that flightcrew members working in all-
cargo operations fly fewer total hours than their passenger-
transporting counterparts. The industry commenters concluded by asking
the FAA to either: (1) Retain the existing flight, duty, and rest
regulations that govern supplemental operations, or (2) adopt the
alternative proposal that they have included in their comments.
    Conversely, a number of labor groups submitted comments approving
of a single flight, duty, and rest standard. These groups stated that
they were ``pleased that the FAA has acknowledged the current science
and recognizes that pilot fatigue does not differ whether the pilot is
operating domestically, internationally or in supplemental
operations.'' The NTSB also expressed support for a single flight,
duty, and rest standard, commending the proposed rule for recognizing
that ``human fatigue factors are the same across [domestic, flag, and
supplemental] operations and science cannot support the notion of
allowing longer duty hours for certain subgroups.'' Numerous individual
commenters have also stated that the existing 16-hour duty periods
utilized by supplemental operations result in an unsafe amount of
fatigue.
    In addition to the concerns expressed by the preceding comments,
United Air Lines (United) objected to the applicability of this rule to
flightcrew members who conduct only part 91 operations on behalf of
part 121 certificate holders. United stated that the original reason
for the applicability of this rule to part 91 operations on behalf of
part 121 certificate holders was to ensure that flightcrew members
operating under part 121 did not use part 91 to avoid their flight,
duty, and rest requirements under part 121. Because flightcrew members
who only conduct part 91 operations cannot conduct part 121 flights,
United argued that these flightcrew members should not be subject to
this rule.
    The FAA also received a number of other questions and concerns
about the applicability of this rule. The NetJets Association of Shared
Aircraft Pilots (NJASAP) asked how this rule would apply to certificate
holders who operate under several different parts of the regulation
(e.g., Part 121, Part 135, Subpart 91K). The Regional Airline
Association (RAA) asked the FAA to amend this section in order to
clarify that this rule applies to ``operations directed by the
certificate holder under part 91 of this chapter.'' In addition, a
number of part 135 certificate holders objected to having their
operations included in the proposed flight, duty, and rest
requirements. These commenters asserted that part 135 operations are
fundamentally different from part 121 operations, and thus, these
operations should not be subject to the same requirements.
    In response to concerns expressed by part 135 certificate holders,
the FAA emphasizes that this rule does not apply to part 135
operations. If, in the future, the FAA initiates a rulemaking to change
the existing part 135 flight, duty, and rest regulations, the FAA will
solicit comments from the affected stakeholders and respond to part-
135-specific concerns at that time.
    Turning to concerns expressed by United, this rule applies to some
part 91 operations because many flightcrew members involved in part 121
operations have routinely used part 91 as a way of exceeding the limits
imposed by the part 121 flight, duty, and rest requirements. However,
the FAA agrees with United that there is no reason to require
flightcrew members who do not fly any part 121 operations to comply
with part 121 flight, duty, and rest requirements. Accordingly, the FAA
has amended this rule so that it applies to flightcrew members
operating under part 91 only if at least one their flight segments is
operated under part 117. Flightcrew members operating under part 91 and
who do not have any flight segments subject to part 117 (e.g. pilots
flying only part 91 operations) are not subject to the provisions of
this rule.
    Turning to concerns expressed by air carriers conducting all-cargo
operations, as discussed in the regulatory evaluation, the FAA has
determined that this rule would create far smaller benefits for all-
cargo operations than it does for passenger operations. Consequently,
the FAA is unable to justify imposing the cost of this rule on all-
cargo operations. The FAA notes that in the past it has excluded all-
cargo operations from certain mandatory requirements due to the
different cost-benefit comparison that applies to all-cargo operations.
For example, in 2007, the FAA excluded all-cargo operations of
airplanes with more than two engines from many of the requirements of
the extended range operations (ETOPS) rule because the cost of these
provisions for all-cargo operations relative to the potential societal
benefit was simply too high.\10\
---------------------------------------------------------------------------

    \10\ 72 FR 1808, 1816 (2007).
---------------------------------------------------------------------------

    Based on the cost-benefit analysis of this rule and its past
precedent, the FAA has amended this rule to make compliance with part
117 voluntary for all-cargo operations and to allow those operations to
continue operating under the existing part 121 flight, duty, and rest
regulations if they choose to do so. As such, this rule now allows all-
cargo operations to voluntarily determine, as part of their collective
bargaining and business decisions, whether they wish to operate under
part 117.
    In order to prevent manipulation of this voluntary provision,
certificate holders who wish to operate their all-cargo operations
under part 117 cannot pick and choose specific flights to operate under
this rule. Instead, the certificate holders can only elect to operate
under part 117: (1) All of their all-cargo operations conducted under
contract to a U.S. government agency; and (2) all of their all-cargo
operations

not conducted under contract to a U.S. Government agency.
    Turning to the objections expressed by non-scheduled passenger
operations, the FAA notes that existing regulations set out different
flight, duty, and rest standards for part 121 domestic, flag, and
supplemental operations. Under these regulations, supplemental
operations consist of non-scheduled, all-cargo, and public-charter
flights. The existing regulations provide supplemental operations with
significant scheduling flexibility because they allow air carriers
conducting supplemental operations to schedule unaugmented flightcrew
members for 16-hour FDPs \11\ and augmented flightcrew members for 30-
hour FDPs \12\ regardless of the time of day.\13\
---------------------------------------------------------------------------

    \11\ 14 CFR 121.505(b). The existing regulations do not regulate
FDPs, but instead, regulate the length of duty time. The FAA
believes that duty time, as used in the existing regulations, is
roughly equivalent to the concept of an FDP because flightcrew
members typically begin and end their duty periods at about the same
times as an FDP, as defined by this rule, would begin and end.
    \12\ 14 CFR 121.523(c).
    \13\ An unaugmented flight contains the minimum number of
flightcrew members necessary to safely pilot an aircraft. An
augmented flight contains additional flightcrew members and at least
one onboard rest facility, which allows flightcrew members to work
in shifts and sleep during the flight.
---------------------------------------------------------------------------

    The FAA acknowledges that this rule will significantly impact
supplemental passenger operations because it reduces the existing 16-
and 30-hour across-the-board limits. This section discusses these
reductions and why they are justified in light of the flexibility
concerns of non-scheduled passenger operations. The other changes made
by this rule that affect supplemental operations are discussed in the
other parts of this preamble.
    The FAA has decided to impose the same FDP limits on supplemental
passenger operations as other part 121 operations because it has
determined that the 16-hour unaugmented FDP and the 30-hour augmented
FDP permitted by existing supplemental flight, duty, and rest
regulations are almost always unsafe for passenger operations.\14\ As
discussed in other parts of this preamble, a series of studies
analyzing the national accident rate as a function of the amount of
hours worked have shown that after a person works for about eight or
nine hours, the risk of an accident increases exponentially for each
additional hour worked.\15\ According to these studies, the risk of an
accident in the 12th hour of a work shift is ``more than double'' the
risk of an accident in the 8th hour of a work shift.\16\ Based on this
exponential increase in the accident rate, the FAA has determined that
the risk of an accident in the 16th hour of an unaugmented FDP rises to
unacceptable levels for passenger operations, especially for shifts
that take place during the WOCL. The FAA has also determined, based on
the above data, that a 30-hour FDP likewise poses an unacceptably high
risk of an accident for passenger operations even with the fatigue-
mitigation benefits provided by augmentation.
---------------------------------------------------------------------------

    \14\ The FAA notes that this rule technically allows an
unaugmented flightcrew member to work on a 16-hour FDP if a 14-hour
FDP is extended through the use of a 2-hour FDP extension. However,
a 14-hour unaugmented FDP is only permitted during periods of peak
circadian alertness, and the 2-hour FDP extension is subject to
additional safeguards. A 30-hour FDP is never permitted, although a
carrier could potentially develop an FRMS that allowed a 30-hour FDP
in augmented operations.
    \15\ See Simon Folkard & Philip Tucker, Shift work, safety and
productivity, Occupational Medicine, Feb. 1, 2003, at 98 (analyzing
three studies that reported a trend in risk over successive hours on
duty).
    \16\ Id. The FAA notes that the Federal Motor Carrier Safety
Administration, another DOT agency, has examined studies comparing
crash risk to hours worked in certain truck operations. Similar to
the Folkard & Tucker study, these studies found a steady rise in
crash risk with additional work hours; however, they did not show an
increase as rapid as the results reported by Folkard and Tucker.
(See, for example, Blanco, M., Hanowski, R., Olson, R., Morgan, J.,
Soccolich, S., Wu, S.C., and Guo, F., ``The Impact of Driving, Non-
Driving Work, and Rest Breaks on Driving Performance in Commercial
Motor vehicle Operations,'' FMCSA, April 2011).
---------------------------------------------------------------------------

    In determining that a 16-hour unaugmented and a 30-hour augmented
FDP is unsafe for passenger operations, the FAA has also taken into
account the fact that aviation-specific data shows that FDPs of this
length significantly increase the risk of an accident. A study
published in 2003 analyzed the accident rate of pilots as a function of
the amount of time that the pilots spent on duty.\17\ The study found
that:
---------------------------------------------------------------------------

    \17\ Jeffrey H. Goode, Are pilots at risk of accidents due to
fatigue?, Journal of Safety Research 34 (2003) 309-13.

    [T]he proportion of accidents associated with pilots having
longer duty periods is higher than the proportion of longer duty
periods for all pilots. For 10-12 hours of duty time, the proportion
of accident pilots with this length of duty period is 1.7 times as
large as for all pilots. For pilots with 13 or more hours of duty,
the proportion of accident pilot duty periods is over five and a
half times as high.\18\
---------------------------------------------------------------------------

    \18\ Id. at 311.

    Because studies examining the national accident rate and aviation-
specific accidents have both shown that working over 13 hours
significantly increases the risk of an accident, the FAA has decided to
disallow the 16-hour unaugmented and 30-hour augmented FDPs currently
permitted in supplemental passenger operations by subjecting
supplemental passenger operations to the same FDP limits as other part
121 passenger operations. The effect that other provisions of this rule
will have on supplemental passenger operations and the reasons why the
FAA has chosen to adopt these provisions are discussed in the
corresponding portions of this preamble.
    The FAA understands that including supplemental passenger
operations in this rule will take away a portion of the scheduling
flexibility currently enjoyed by non-scheduled passenger operations.
However, this rule contains a number of provisions that ease the burden
of current rules on non-scheduled operations in a way that does not
decrease safety.
    The most significant way in which this rule eases the burden of
existing rules on supplemental passenger operations is the elimination
of compensatory rest requirements. Under the existing rules, a pilot
who flies an aircraft for over 8 hours in a supplemental operation must
receive a compensatory rest period that is 16 hours or longer
(depending on whether the flight was augmented) at the conclusion of
his or her duty day. This compensatory rest requirement imposed a
significant burden on supplemental passenger operations because pilots
had to be provided with at least 16 hours of rest simply for flying for
9 hours. In addition, the FAA found that by focusing on flight time and
not on FDP, the existing supplemental flight, duty, and rest
regulations led to counterintuitive results in which long 16- and 30-
hour FDPs were permitted with only a 9-hour required rest period, but a
9-hour flight time with a relatively-short FDP resulted in a 16- to 18-
hour required rest period.
    In order to address the concerns discussed in the preceding
paragraph and because there was an absence of scientific data showing
that rest periods providing for more than 8 hours of sleep were always
necessary to combat transient fatigue, this rule eliminates the
existing compensatory rest requirements for supplemental passenger
operations. The removal of this additional rest requirement will allow
certificate holders conducting non-scheduled passenger operations to
fly augmented international operations, including those that are under
contract with the United States Government, without having to provide
flightcrew members with an additional 6 hours of rest at the end of the
operation. In addition, to ensure that certificate holders

conducting supplemental operations are able to provide critical
services in support of government operations, this rule also contains
an Emergency and Government Sponsored Operations section that allows
operations performed in accordance with a government contract to exceed
this rule's flight, duty, and rest limits in certain situations.
    Another example of a provision in this rule that benefits
supplemental passenger operations is the increase of the flight-time
limits for augmented and unaugmented flights. This increase will allow
certificate holders conducting supplemental operations to schedule
unaugmented flightcrew members for 9 hours of flight time during peak
circadian times after providing them with only 10 hours of rest. The
existing regulations would require certificate holders conducting
supplemental operations to provide their flightcrew members with 18
hours of rest after an operation involving 9 hours of unaugmented
flight time.
    In addition to including provisions that ease the burden of the
maximum-FDP-limit reduction on supplemental operations, the FAA has
also made adjustments to this rulemaking in response to concerns raised
by air carriers (certificate holders) conducting non-scheduled
passenger operations. Thus, the FAA has: (1) Increased the unaugmented
and augmented FDP limits in Tables B and C, (2) increased the amount of
the split-duty credit and made that credit easier to obtain, and (3)
largely eliminated the scheduling reliability requirements that were
proposed in the NPRM. All of these adjustments were made, at least in
part, in response to the concerns raised by certificate holders
conducting non-scheduled operations, and they should significantly ease
the burden of this rule on these types of operations. In making these
adjustments, the FAA has, where possible, incorporated into this rule
portions of the alternative proposal put forward by the industry
commenters who conduct non-scheduled passenger operations.
    While air-carrier business models for passenger operations may
differ, the factors that give rise to unsafe levels of fatigue are the
same for each flightcrew member involved in these operations. A
flightcrew member working a 16 or 30-hour FDP as part of a supplemental
passenger operation will not be less tired simply because he or she is
working in a supplemental type of operation instead of a domestic type
operation. To account for this fact and ensure that fatigue is limited
to safe levels, the FAA has decided to set a single flight, duty, and
rest standard for all part 121 certificate holders conducting passenger
operations. The FAA is sympathetic to the fact that supplemental
passenger operations require additional flexibility that is not
required by other business models and as a result, may bear a
disproportionate cost of this rule. To ameliorate the cost of this
rulemaking on supplemental operations, this rule contains supplemental-
friendly provisions and adjustments that do not have an adverse effect
on safety. However, the flexibility and cost-savings required by
supplemental passenger operations can no longer be used to justify 16
and 30-hour FDPs for these operations because scientific studies have
shown that FDPs of this length significantly increase the risk of an
aviation accident that could injure passengers onboard an aircraft.
    In response to NJASAP's question, the FAA notes that this rule
applies to all part 121 certificate holder passenger operations and all
part 121 and part 91 operations where an FDP includes at least one
flight segment conducted under part 117. Thus, if a flightcrew member
flies one or more segments of an FDP in passenger-carrying operations,
but also flies a part 91 positioning flight as part of that FDP, the
part 91 flight would have to be conducted under part 117. Parts 135 and
91K have their own set of flight, duty, and rest requirements that will
continue to apply to those operations.

B. Definitions

    The NPRM included definitions specific to this part. The
definitions adopted in this rule are in addition to those in Sec. Sec.
1.1 and 110.2. In the event that terms conflict, the definitions in
part 117 control for purposes of the flight and duty regulations
adopted in this rule. The section below provides a discussion of the
specific definitions used in the final rule.
1. Acclimated
    The FAA proposed to define ``acclimated'' as a condition in which a
flightcrew member has been in a theater for 72 hours or has been given
at least 36 consecutive hours free from duty.
    The Airline Pilots Association (ALPA), the Allied Pilots
Association (APA), the Coalition of Airline Pilots Associations (CAPA),
and the Independent Pilots Association (IPA) stated that acclimated
should mean a condition in which a flightcrew member has been in a new
theater for the first 72 hours since arriving and has been given at
least 36 consecutive hours free from duty during the 72 hour period.
Also, the Flight Time Aviation Regulation Committee and Flightcrew
Representatives (representing labor) (Flight Time ARC) supported the
suggested, revised definition. These commenters noted that according to
established science, three consecutive local nights' rest is required
to become acclimated. They also noted that Cap 371 provides for three
consecutive local nights rest to become acclimated.
    NACA, North American Airlines (NAA), World Airways, and Atlas Air
Worldwide Holdings, Inc. (Atlas) contended that the proposed definition
should be revised to allow 30 consecutive hours free from duty instead
of 36 hours.
    NACA and NAA said that it is important in regulations controlling
both schedules and operations that the extended rest periods be
consistent across domestic and international operations. NACA, NAA, and
World Airways said that the FAA's proposed acclimation time should be
changed to reflect the agency's proposed 168-hour look-back rest period
of 30 hours. (See Sec.  117.25(b)). These commenters believed that 30
hours is appropriate because any further time to acclimate may preclude
flightcrew members from returning to their home base as flightcrew
members, which becomes important in commercial operations where flight
hours are guaranteed.
    World Airways said that its recommendation of 30 hours free from
duty is within the range the ARC discussed as sufficient for
acclimation to occur. Atlas said that there is no scientific
justification for selecting 36 as the minimum number of consecutive
hours. Atlas further commented that subsequent to publication of the
NPRM, the FAA clarified its definition of acclimated, stating that the
computation is based on actual, not scheduled, operations. Atlas
believed that this clarification needs to be incorporated into the
definition as follows: ``Time in theater begins upon block in at an
airport more than four time zones from the previous acclimated
location.''
    In response to the above comments, the FAA is not persuaded by the
argument that acclimation only can occur when the flightcrew member is
in a new theater for 72 hours and has been given 36 consecutive hours
free from duty during that period. The Flight Time ARC did receive
information from the sleep specialists that an individual attempting to
acclimate to a new time zone will adjust his or her clock approximately
one hour per day for each hour of time zone difference. 75 FR 55852,
55861 (Sep. 14, 2010). The ARC, however, concluded that, based on its
collective experience, acclimation can

occur more quickly if the flightcrew member manages the sleep
opportunity appropriately. The ARC also concluded that a flightcrew
member can become acclimated by either receiving three consecutive
physiological nights' rest or a layover rest period of 30 to 36
consecutive hours. The ARC universally rejected the premise that,
because the United Kingdom is 5 time zones away from the eastern coast
of the United States, it would take between five and nine days to
acclimate to a European time zone. The commenters did not present new
information that was not considered during the ARC. There is no
compelling information or argument that refutes the body of experience
represented in the ARC and the FAA declines to amend this definition as
suggested.
    The FAA also declines to accept the suggestion that a 30 hour rest
period is adequate to acclimate compared to the 36 hour period proposed
in the NPRM. The ARC recommended a 30 to 36 hour layover rest period.
The FAA decided to propose the 36-hour rest period because it provides
for one physiological night's rest and then opportunity for a shorter
rest period. The agency finds that the more conservative approach is
appropriate to provide the more meaningful opportunity for rest.
    United Parcel Service Co. (UPS) commented that administrative
duties should be exempted or removed from the scope of flight duty when
determining flightcrew member acclimation. UPS further commented that
if flightcrew members revised company manuals or navigation charts
during a duty free period (layover) or prior to report time, it is
possible that the flightcrew members would not satisfy the definition
of being acclimated or could drive different FDP limits based on when
they claim their duties started.
    In response to UPS' concern, to acclimate a flightcrew member under
this rule, the certificate holder must provide the required rest and
cannot assign any duties during the rest period. Similarly, it is the
flightcrew member's responsibility to take advantage of the period and
rest accordingly. If a flightcrew member independently decides to
perform administrative type duties during this time period, as
described by the commenter, the flightcrew member is considered
acclimated regardless of whether he or she actually rested during this
time period.
2. Acclimated Local Time
    While the FAA did not propose this term, ALPA, CAPA, Flight Time
ARC, and the Southwest Airlines Pilots Association (SWAPA) suggested
including this term. They suggested that acclimated local time means
the local time at the location where the pilot last had greater than 36
hours free from duty in the first 72 hours in theater. IPA recommended
the same definition, except it replaced the term ``pilot'' with
``flightcrew member.'' In support of their recommendation, ALPA, CAPA,
and Flight Time ARC said this new definition would provide an
unambiguous time for applying the definition of ``nighttime duty
period'' and for entering the FDP and flight time limit tables. They
further said that the wording in the NPRM concerning acclimated or home
base time left many questions of interpretation. For example, a USA-
based pilot who acclimates in Europe and then subsequently flies to
Japan would, under the current NPRM wording, enter the tables at home-
base time instead of Europe time. The commenters also stated that the
exact location of acclimation must be known to determine future loss of
acclimation. Under their proposal, the commenters contended that both
the tables and the definition of nighttime flight duty period would use
the new term, ``acclimated local time.''
    The FAA has accommodated these concerns by changing the heading of
Tables A, B, and C to reflect acclimated time. In addition, the FAA
clarifies that a flightcrew member is considered acclimated based on
which rest he or she was given first. If the flightcrew member
completes 36 consecutive hours of rest prior to being in theater for 72
hours, then the flightcrew member is acclimated at the time that the
36-hour period ends and he or she is acclimated at the location that
the rest occurred.
3. Airport/Standby Reserve
    According to the proposed definition, ``Airport/standby reserve''
means a defined duty period during which a flightcrew member is
required by a certificate holder to be at, or in close proximity to, an
airport for a possible assignment.
    UPS said that the FAA's definition of airport/standby reserve is
too vague and is open to interpretation. It recommended revising the
definition to mean an assignment that requires a flightcrew member to
be in a position to begin preflight activities following notification
of an assignment without requiring additional travel time to arrive for
the operation.
    NACA and NAA did not believe that the definition is necessary
because airport/standby reserve is an assignment within an FDP. If the
term is adopted, NACA and NAA recommended that the term be defined as a
duty period during which a flightcrew member is required by a
certificate holder to be at, or in close proximity to, an airport for a
possible assignment, and to show at the departure gate or aircraft
within one hour.
    Atlas contended that the FAA did not clarify the relationship of
airport/standby reserve and short-call reserve in its clarification
document published after the NPRM. This commenter noted that according
to the FAA's clarification, airport/standby reserve and short-call
reserve are mutually exclusive. Atlas said that the distinction was
explained as whether or not the flightcrew member is ``at the airport
or in close proximity to the airport.'' If at or in close proximity to
the airport, a flightcrew member is deemed to be on airport/standby
reserve, this suggests that a flightcrew member on short-call reserve
in a hotel room near an airport could be deemed to be on airport/
standby reserve. Atlas believed the distinction is important because it
determines if the reserve is counted as part of the FDP. Atlas argued
that airport/standby reserve means a defined duty period at an on-
airport facility to which a flightcrew member has been required to
report by a certificate holder immediately following assignment
(usually within one hour) and at which no rest facilities are available
or no rest is scheduled.
    The FAA agrees that the proposed terminology could be confusing and
has modified the term to mean a duty period during which a flightcrew
member is required by a certificate holder to be at an airport for
possible assignment.
4. Augmented Flightcrew
    The NPRM defined ``augmented flightcrew'' as a flightcrew that has
more than the minimum number of flightcrew members required by the
airplane type certificate to operate the aircraft to allow a flightcrew
member to be replaced by another qualified flightcrew member for in-
flight rest.
    A number of industry commenters objected to the fact that the
proposed augmented flightcrew definition did not allow a flight
engineer to augment a pilot. These commenters stated that adding a
flight engineer to a flightcrew has a number of safety benefits. The
commenters added that their inability to augment with a flight engineer
would result in three-seat aircraft being retired prematurely, which
would raise the costs of this rule.
    This rule does not allow augmentation with a flight engineer for

safety reasons. As discussed more fully in other parts of this
preamble, an augmented flight provides fatigue-mitigation benefits
because it contains more than the minimum number of pilots, and the
additional pilots allow the flightcrew to obtain in-flight rest by
working in shifts and replacing each other at the aircraft controls.
However, a flight engineer is not qualified to manipulate the flight
controls and pilot an aircraft and is generally prohibited from
occupying a pilot duty station. Because a flight engineer who is not
qualified as a pilot cannot occupy a pilot duty station, an engineer
cannot replace a pilot at the aircraft controls. As such, this rule
does not allow a pilot to be augmented with a flight engineer.
    With regard to three-seat aircraft, even though this rule does not
give augmentation credit for a flight engineer to augment a pilot, it
does not prohibit flight engineers from working on three-seat aircraft.
All this rule states is that, without additional pilots, a flightcrew
that has a flight engineer would not be considered augmented. Because a
flight engineer could still work on a three-seat aircraft under the
terms of this rule, the FAA does not believe that the above limitation
on augmentation would lead to the premature retirement of three-seat
aircraft.
5. Calendar Day
    The NPRM proposed that a ``calendar day'' means a 24-hour period
from 0000 through 2359.
    Alaska Airlines said that while the FAA contends in its clarifying
document that the calendar day for the flightcrew member's home base
should be sufficient, calendar day as defined in the NPRM does not
provide this clarification. Alaska Airlines instead recommended that a
calendar day means a 24-hour period from 0000 through 2359 local time
at the flightcrew member's home base.
    Boeing Commercial Airplanes (Boeing) suggested a similar definition
to address frequent transitions between time zones. Boeing further
stated that rules such as the ones proposed in the NPRM are implemented
in computerized optimization systems for crew scheduling, and as a
result, ambiguities in the rules can lead to different interpretations.
    The FAA has amended this term to include reference to Coordinated
Universal Time or local time. This is consistent with the definition of
calendar day in section 121.467(a) (Flight attendant duty period
limitations and rest requirements: Domestic, flag, and supplemental
operations).
6. Consecutive Night Duty Period
    The FAA did not propose a definition for this term; ALPA, CAPA,
SWAPA, Flight Time ARC, and Federal Express Air Line Pilots
Association, International (FedEx ALPA) said that the proposed Sec.
117.27 limits consecutive nighttime flight duty periods to three
periods. To avoid confusion in applying Sec.  117.27, the commenters
believed that the term ``consecutive night duty period'' should be
defined. They recommended that consecutive night duty period mean two
or more night flight duty periods that are not separated by at least a
part Sec.  117.25 rest between the duty periods that encompasses a
physiological night's sleep (1 a.m. to 7 a.m. at home base or
acclimated local time). IPA suggested the adoption of a similar
definition.
    The FAA declines defining the term consecutive night flight duty
period and instead includes a provision in Sec.  117.27 to address the
commenters' concerns. Section 117.27 now specifies that the
consecutive-night provisions apply to consecutive flight duty periods
that infringe on the WOCL. The WOCL is defined later in this section.
7. Deadhead Transportation
    As proposed, ``deadhead transportation'' means transportation of a
flightcrew member as a passenger, by air or surface transportation, as
required by a certificate holder, excluding transportation to or from a
suitable accommodation.
    Air Transport Association of America, Inc. (ATA) suggested removing
the word ``passenger'' from the definition because the FAA should not
assume that deadhead transportation should be limited to flightcrew
members characterized as passengers when not all carriers carry
passengers. Similarly, UPS commented that the proposed definition fails
to address deadhead transportation on aircraft not configured for
passenger operations (i.e., all-cargo aircraft). UPS suggested that the
FAA revise the definition as follows: ``Deadhead transportation means
transportation of a flightcrew member as a passenger, non-assigned
flight deck occupant, or other additional flightcrew member by air or
surface transportation, as required by the certificate holder,
excluding transportation to or from a suitable accommodation.''
    The FAA agrees with the above commenters and has modified the term
to apply to the transportation of a flightcrew member as a passenger or
a non-operating flightcrew member. The FAA has also added two
clarifying statements to the definition. The first is that all time
spent in deadhead transportation is duty and is not rest. This
provision was copied from proposed Sec.  117.29 Deadhead
transportation. Secondly, the FAA includes in this definition that
deadhead transportation is not considered a segment for purposes of
determining the maximum flight duty period in Table B.
8. Duty
    The NPRM defines ``duty'' to mean any task, other than long-call
reserve, that a flightcrew member performs on behalf of the certificate
holder, including but not limited to airport/standby reserve, short-
call reserve, flight duty, pre-and post-flight duties, administrative
work, training, deadhead transportation, aircraft positioning on the
ground, aircraft loading, and aircraft servicing.
    Industry commenters largely rejected the proposition that short-
call reserve be considered duty. They argued that this classification
is inappropriate and unrelated to effective fatigue mitigation. They
also stated that the only requirement or company task a pilot has on
short call reserve is to be available to be contacted. Otherwise, the
pilot is free to do what he or she wants and plans the day to take
advantage of rest opportunities or any other activities as he or she
desires, just as a lineholder would. Industry also largely objected to
the classification of short-call reserve as duty. ALPA, CAPA, FedEx
ALPA, SWAPA and APA all commented favorably on short call reserve being
considered duty.
    As stated in the NPRM, the FAA's rationale for this proposal was
that while on short-call reserve, the flightcrew member can expect that
he or she will not receive an opportunity to rest prior to commencing
an FDP. Additionally, the flightcrew member is required to limit his or
her action sufficiently so that he or she can report to the duty
station within a fairly short timeframe. The FAA believed that this
time should be accounted for under the cumulative limitations and
therefore proposed that short-call reserve be considered duty.
    However, the commenters argued that a flightcrew member on short-
call reserve has the same predictable rest and sleep opportunities as a
regularly-scheduled lineholder and that being on reserve cannot entail
significant workload and thereby be fatiguing. The FAA accepts that
while reserve cannot be categorized as ``rest'' it does not necessarily
fit squarely with being considered duty either. As the commenters
correctly pointed out, time

spent on short-call reserve is simply not as fatiguing as time spent on
an FDP. Therefore, this rule no longer includes short-call reserve as
duty.
    ATA, NACA, UPS, United, Continental Airlines, Inc. (Continental),
Alaska Airlines, NAA, Delta Air Lines (Delta), and World Airways stated
that the proposed definition of duty is too broad, operationally
unworkable, and not clear regarding accountability. They objected to
the inclusion of the terms ``any task,'' ``on behalf of the certificate
holder,'' and ``administrative work'' in the definition. ATA provided
the example of a professional pilot who routinely performs tasks such
as refreshing outdated publications, watching videos for recurrent
training, and reading and responding to emails. Because a flightcrew
member can perform these tasks at a time and place of his or her
choosing, the commenters argued that a certificate holder has no way of
knowing or controlling the pertinent flightcrew member conduct.
    ATA asserted that the inclusion of administrative but not labor-
related work in the definition does not make sense because no material
distinction exists between administrative tasks performed on behalf of
management and similar tasks performed on behalf of labor.
    Alaska Airlines said that the FAA in its clarifying document noted
that the term ``administrative work'' is readily understandable;
however, the commenter noted that the term's role in fatigue and in the
context of the regulation is vague. The commenter believed that the
term needs further clarification and should only include work
associated with flight operations.
    Continental and United said that the definition of duty considers
administrative work in the same way that it assesses flight duty. They
contend that this is inappropriate when applied to the cumulative duty
restrictions discussed in proposed Sec.  117.23.
    Alaska Airlines suggested that the FAA make clear in the final rule
that duty only includes activities that the carrier can directly
control. ATA recommended clarifying the definition by replacing the
phrase ``on behalf of the certificate holder'' with ``directed by a
certificate holder on company property.'' NACA, UPS, Delta, and World
Airways suggested revising the definition of duty to mean ``any task,
other than long-call and short-call reserve, that is directed by the
certificate holder * * *'' NAA believed the term ``on behalf of the
certificate holder'' should be replaced with ``is assigned by the
certificate holder.''
    UPS contended that the FAA must address the issue of management
pilot duty and suggested that management pilot duty include all time
spent during company business-related meetings and other business-
related activity conducted on company property. UPS argued that if this
is not addressed, management pilots will effectively become non-flying
pilots.
    NACA, World Airways, and NAA recommend deleting the term
``administrative work'' because it is too vague and inclusive of issues
that have nothing to do with direction by the certificate holder or FDP
fatigue mitigation. Continental and United recommended that the FAA
remove administrative activity from the definition and add a provision
to the regulation that applies administrative duty to specific FDPs.
ATA and Delta request that if the term is kept in the definition, the
FAA should clarify that the definition treats management and labor-
related administrative work in the same way.
    In response to the above comments, the definition of duty has been
further modified by replacing ``on behalf'' of the certificate holder
with ``as required'' by the certificate holder. This addresses the
certificate holders' concern that the administrative work accomplished
by the flightcrew member is work that he or she is required to do, and
appropriately included as duty. Lastly, the FAA agrees that performance
of administrative management work is not distinguishable from any other
type of administrative work, and therefore administrative management
work is included in the term ``administrative work'' under this
definition.
9. Duty Period
    As proposed, ``duty period'' means a period that begins when a
certificate holder requires a flightcrew member to report for duty and
ends when that crew member is free from all duties.
    UPS said that defining the end of the duty period as ``* * * free
from all duties'' is too ambiguous and uncertain since a certificate
holder cannot control voluntary duties that a flightcrew member may
decide to accomplish at the end of his or her FDP. UPS suggested that
the definition be changed so that the end of the duty period occurs
when the flightcrew member is ``* * * released from all company
directed duties.'' In light of the changes that have been made to this
rule, the FAA has determined that it is no longer necessary to define
this term, and therefore the proposed definition is withdrawn.
10. Early Start Duty
    The NPRM did not propose a definition for this term, however, APA
recommended including the term, which would mean an FDP that commences
in the period 0500 to 0659 home base time or where acclimated. The FAA
does not agree that adopting this term is necessary or useful.
11. Fatigue
    Fatigue as proposed means physiological state of reduced mental or
physical performance capability resulting from lack of sleep or
increased physical activity that can reduce a flightcrew member's
alertness and ability to safely operate an aircraft or perform safety-
related duties.
    ATA commented that the proposed definition of fatigue is
inconsistent with ICAO's proposed definition. ATA noted that ICAO
proposes to define fatigue as ``a physiological state of reduced mental
or physical performance capability resulting from sleep loss or
extended wakefulness, circadian phase, or workload (mental and/or
physical activity) that can impair a crew member's alertness and
ability to safely operate an aircraft or perform safety related
duties.'' ATA recommended adopting the ICAO definition because it
captures the fatigue-inducing effects of the interaction of sleep loss,
circadian phase, and workload, and provides a scientific basis for
fatigue risk management.
    In response to ATA's comments, the FAA notes that ICAO has not
finalized its definition of fatigue, and the proposed definition may be
subject to change. At this point, it is not prudent for the FAA to
include a term that ultimately may be changed or not even adopted.
Therefore, the FAA is adopting the definition of fatigue that was
proposed.
12. Fit for Duty
    As proposed, the definition of ``fit for duty'' means
physiologically and mentally prepared and capable of performing
assigned duties in flight with the highest degree of safety.
    UPS commented that including ``* * * duties in flight with the
highest degree of safety'' in the definition of ``fit for duty'' is not
practical and too subjective. UPS further stated that it is unrealistic
for any human to be at their ``highest'' level of performance during
every possible FDP and suggests replacing ``* * * highest degree of
safety'' with ``* * * capable of performing duties that assure flight
safety.''
    The FAA does not agree with UPS because every flightcrew member on

every flight should be prepared and capable of performing the assigned
duties at the highest degree of safety. Accordingly, the FAA has
adopted the proposed definition in the final rule.
13. Flight Duty Period
    The NPRM defines ``flight duty period'' to mean a period that
begins when a flightcrew member is required to report for duty with the
intention of conducting a flight, a series of flights, or positioning
or ferrying flights, and ends when the aircraft is parked after the
last flight and there is no intention for further aircraft movement by
the same flightcrew member. A flight duty period would include deadhead
transportation before a flight segment without an intervening required
rest period, training conducted in an aircraft, flight simulator or
flight training device, and airport/standby reserve.
    ATA, UPS, World Airways, NAA, NACA, Delta, and Alaska Airlines
objected to including all flight training in a flight simulator or
training device in the definition of FDP. ATA, Delta, and Alaska
Airlines commented that there is no scientific basis for such
inclusion, and all seven commenters said there is no inherent safety
basis for this decision. Alaska Airlines and Delta added that with
simulator time included in the FDP, pursuant to section 117.27,
flightcrew members would be unable to participate in simulator training
on more than three consecutive nights. ATA further commented that there
is no basis for including travel to a training site in the FDP unless
the travel occurs before flight time.
    ATA, Delta, and Alaska Airlines recommended that the FAA revise the
proposed definition to state that only training and flight simulator
time conducted before a flight without an intervening rest period is
counted as part of the FDP. UPS said that it supports counting time
spent in a simulator or flight training device as part of an FDP only
if this time immediately precedes flight duty without an intervening
rest period. UPS believed that there is an unintended consequence of
treating simulator and flight training device training as part of an
FDP, regardless of when the training occurs. That is, the practice of
providing additional training to a flightcrew member who requests that
training will be discontinued; thereby, affecting flight safety.
    NACA, NAA and World Airways commented that an FDP ``must involve a
flight, or at a minimum, movement of an aircraft where the public is at
risk where an aircraft accident potential immediately exists.'' They
suggested revising the proposed definition to add the following
phrases: ``but not limited to'' and ``whenever these duties are
performed in conjunction with duties involving flight without an
intervening rest period.'' This would result in a definition that
reads: ``* * * A flight duty period includes, but is not limited to,
deadhead transportation * * * and airport/standby reserve whenever
these duties are performed in conjunction with duties involving flight
without an intervening rest period.''
    The FAA clarifies that an FDP begins when the flightcrew member
reports for duty and will include the duties performed by the
flightcrew member on behalf of the certificate holder that occur before
a flight segment or between flight segments without a required
intervening rest period. The FDP ends when the aircraft is parked after
the last flight and there is no intention for further aircraft movement
by the same flightcrew member. Included in the FDP are any of the
following actions if they occur before a flight segment or between
flight segments without an intervening rest period: deadhead
transportation, training conducted in an aircraft or flight simulator,
and airport/standby reserve. Time spent in a flight training device
that takes place after the aircraft has been parked after the last
flight has been eliminated from this definition. For purposes of
calculating the pertinent part 121 flight, duty, and rest limits, the
FAA considers time spent on an FDP to be duty.
14. Flight Time
    The NPRM did not propose a definition for this term; however, APA,
ALPA, CAPA, FedEx ALPA, SWAPA, and Flight Time ARC recommended adding a
definition for flight time to begin when the aircraft first moves with
the intention of flight. These commenters argued that this term in
Sec.  1.1 is defined as the moment the aircraft first moves under its
own power. However, the pilot in command (PIC) and required flight deck
flightcrew members are always responsible and must perform their duties
when the aircraft is moved by a tug or sits on a hardstand and that
time should count, according to the commenters, as flight time if the
movement is with the intention for flight. They also state that this
definition would be consistent with Annex II, Subpart Q to the
Commission of the European Communities Regulation No. 3922/91, as
Amended (EU OPS subpart Q) which defines flight time as the time
between an airplane first moving from its parking place for the purpose
of taking off until it comes to rest on the designated parking position
and all engines or propellers are stopped.
    IPA suggested that the proposed definition be revised as follows:
``Flight time means when the aircraft first moves with the intention of
flight until it comes to rest on the designated parking position.''
    The FAA declines the commenters' recommendations. Numerous other
regulations are based on the definition of flight time that is set out
in Sec.  1.1. Changing this term solely in the context of the flight
and duty regulations would make this rule more complicated than
necessary and create confusion between this rule and other regulations.
15. Late Finish Duty
    The NPRM did not propose a definition for this term; however, APA
said a definition of ``late finish duty'' is needed to provide for
fatigue mitigation caused by consecutive early starts and late
finishes. APA suggested that the term be defined as an FDP that ends
during the period of 0000-0159, home base time or where acclimated. The
FAA does not find that it is necessary or useful to adopt this term.
16. Night and Nighttime
    The FAA did not propose definitions for either of these terms;
however, NACA and NAA said that the FAA's intent for using the term
``night'' in the NPRM should be defined. If it is not defined, the
commenters said that the FAA should always use the term ``physiological
night'' in all text in the preamble and in the final rule. They
recommended defining night to mean ``the period between 0100 and 0700
at the flightcrew member's designated home base or acclimated
location.'' The commenters noted that this would make the term
compatible with the definition of ``physiological night's rest.''
    Atlas said that the final rule should contain a definition of the
terms ``night'' and ``nighttime,'' so as to make the meanings
comparable to references in proposed Sec.  117.27, as well as to the
definition of ``physiological night's rest.'' It noted that while
``physiological night's rest'' refers to the hours of 0100 and 0700,
the term ``nighttime'' referenced in proposed Sec.  117.27 is
interpreted to refer to operations that commence between 2200 and 0500,
according to page 22 of the FAA's clarification document. Both
definitions, the commenter said, differ from the definition of
``night'' in 14 CFR. Sec.  1.1, which is the time between the end of
evening civil twilight and the beginning of morning civil twilight, as
published in the American Air Almanac, converted to local time.

    The FAA declines to adopt these terms. The FAA uses the word
``physiological night's rest'' when it is appropriate. In addition,
please refer to the FAA's response to the term ``Consecutive Night Duty
Period.''
17. Nighttime Flight Duty Period
    The FAA did not propose a definition for this term; however, APA,
ALPA, CAPA, FedEx ALPA, SWAPA, and Flight Time ARC said that to avoid
confusion when conducting consecutive nighttime operations under Sec.
117.27, the FAA should define ``nighttime flight duty.'' They suggested
that this term be defined to mean a duty period during which any part
of the duty period falls within the home base or acclimated local time
period of 0200 to 0459.
    IPA suggested a definition of ``nighttime flight duty'' as follows:
``a duty period during which any part of the duty period falls within
the home base or acclimated local time period of 0200 to 0459.''
    Please see response to ``6. Consecutive Night Duty Period.'' The
FAA does not find it necessary to define the term as suggested.
18. Nighttime Operations
    ATA said that the FAA should add a new definition of nighttime
operations for purposes of part 117 to be consistent with the agency's
document that responds to clarifying questions to the NPRM. The
commenter believed that the definition should include operations that
commence between 10 p.m. and 5 a.m. The FAA has clarified the pertinent
provisions of section 117.27, and as such, it finds that a separate
definition for nighttime operations is unnecessary.
19. Report Time
    The NPRM defined ``report time'' as the time that the certificate
holder requires a flightcrew member to report for a duty period. The
FAA did not receive any comments with regard to this definition, and as
such, this rule adopts the proposed definition.
20. Reserve Availability Period
    The NPRM defined ``reserve availability period'' to mean a duty
period during which a certificate holder requires a reserve flightcrew
member on short call reserve to be available to receive an assignment
for a flight duty period.
    NACA objected to the premise that short call reserve is duty. It
noted that ARC discussions were clear that short call reserve, which is
a period of time when the only responsibility the crew member has is to
answer the phone, is not a fatiguing event, and thus, it should not
constitute duty for cumulative-duty purposes. NACA suggested revising
the proposed definition so that it reads ``reserve availability period
means a period of time during which a certificate holder requires a
reserve flightcrew member on short call reserve to be available to
receive an assignment for a flight duty period.''
    As discussed in other portions of this preamble, cumulative-duty-
period limits have been removed from this rule. This removal addresses
the concern expressed in NACA's comment as short-call reserve is no
longer subject to the cumulative-duty-period limits.
21. Reserve Duty Period
    The NPRM defined ``reserve duty period'' as the time, applicable
only to short call reserve, from the beginning of the reserve
availability period to the end of an assigned flight duty period. In
light of the changes that were made to the reserve status section, this
definition is no longer necessary, and it has been removed from the
final rule.
22. Reserve Flightcrew Member
    The NPRM defined ``reserve flightcrew member'' as a flightcrew
member who a certificate holder requires to be available to receive an
assignment for duty. The FAA did not receive any comments with regard
to this definition, and as such, this rule adopts the proposed
definition.
23. Rest Facility
    The NPRM defines ``rest facility'' as a bunk, seat, room or other
accommodation that provides a flightcrew member with a sleep
opportunity. In determining what constitutes each specific type of rest
facility, the FAA took note of a comprehensive evaluation of available
onboard rest facilities, which was conducted by the Dutch government in
2007. Simons M, Spencer M., Extension of Flying Duty Period By In-
Flight Relief. Report TNO-DV2007C362. TNO, Soesterberg, Netherlands,
2007 (TNO Report). The TNO Report was created in order to provide
science-based advice on the maximum permissible extension of the FDP
related to the quality of the available onboard rest facility and the
augmentation of the flightcrew with one or two pilots.
    As defined in the NPRM, ``Class 1 rest facility'' means a bunk or
other surface that allows for a flat sleeping position and is located
separate from both the flight deck and passenger cabin in an area that
is temperature-controlled, allows the flightcrew member to control
light, and provides isolation from noise and disturbance. ``Class 2
rest facility'' means a seat in an aircraft cabin that allows for a
flat or near flat sleeping position; is separated from passengers by a
minimum of a curtain to provide darkness and some sound mitigation; and
is reasonably free from disturbance by passengers or flightcrew
members. ``Class 3 rest facility'' means a seat in an aircraft cabin or
flight deck that reclines at least 40 degrees and provides leg and foot
support.
    ATA stated that the proposed rule was overly restrictive with
respect to the facilities it deemed sufficient for conferring credit
for in-flight rest on augmented flights. ATA, NACA, and UPS criticized
the proposal for over-relying on the TNO Report. ATA and UPS emphasized
that the TNO Report is only a single study that has not been adopted by
any regulatory body. NACA asserted that ``the TNO report is more than
10 years old and was proposed by a limited number of scientists and
based upon limited studies.'' NACA added that ``[i]n the ARC
discussions, Dr. Hursh stated that his [SAFTE/FAST] models value sleep
on a bunk at approximately 66 to 80 percent of normal sleep.'' APA
stated that the TNO Report has not been validated in the aviation
context.
    ATA stated that the proposed rule's adoption of the TNO report
would have substantial adverse impacts on U.S. carriers because it
would deviate from the less-restrictive criteria for rest facilities
that the FAA set out in Advisory Circular (AC) 121-31. This is because,
ATA asserted, many air carriers have invested a substantial amount of
money developing rest facilities that comply with the guidelines set
out in AC 121-31, and these facilities would not satisfy the more
stringent criteria for rest facilities set out in the TNO Report. ATA
noted that although it supports the concept of credit for in-flight
rest, it does not support rest facility criteria derived from the TNO
Report. It further noted that ``the FAA should continue to accept AC
121-31 standards for all aircraft built prior to the imposition of the
new rule, the use of current business class seats as Class 2 facilities
and for credit being afforded to all-cargo aircraft that provide a
`horizontal sleep opportunity' to flightcrew members. Rest facilities
in use today built to AC 121-31 standards are operationally validated
as a means of fatigue mitigation that FAA has accepted and there is no
evidence that such facilities should not be used in the future.'' To
minimize costs, ATA recommended that ``[a]t a minimum, the guidance in
AC 121-31 should remain in effect for all aircraft built prior to the
implementation date of the NPRM and

a significant period allowed for newer aircraft to conform to any new
standards.''
    UPS added that most air-cargo carriers would be unable to install
rest facilities needed for the augmentation credit because air-cargo
aircraft do not have passenger cabins. UPS asserted that it would be
unable to install the rest facilities required by this rule in
approximately 18% of its total fleet.
    The existing advisory circular that provides guidance for onboard
rest facilities (AC 121-31) was written in 1994 based on the science
that existed at that time. The TNO Report, on the other hand, was
written in 2007, and it provides the most comprehensive evaluation
available to date of onboard rest facilities. This report may not yet
have been adopted by other regulatory bodies because it is only four
years old, and significant regulatory changes usually take place over a
longer period of time. When drafting this rule, the FAA found the TNO
Report to be more persuasive than AC 121-31 because the TNO Report
performed a comprehensive evaluation of rest facilities, and because it
was based on more recent scientific data than AC 121-31.
    The FAA understands that the TNO Report provides more conservative
conclusions than the pertinent SAFTE/FAST data concerning onboard rest
facilities. However, in response to comments discussed above, the FAA
has increased the augmented FDP limits in Table C. This increase should
more accurately reflect the results of the SAFTE/FAST modeling for
augmented operations.
    The FAA has considered the fact that basing the definition of rest
facilities on the TNO Report may pose hardships for air carriers who
currently rely on AC 121-31 for guidance about onboard rest facilities.
To mitigate this hardship, as well as for a number of other
considerations, the FAA has decided to make the effective date of this
rule two years from publication. This two-year window will provide air
carriers with time to phase out their current onboard rest facilities
and install/upgrade onboard rest facilities that comply with the
provisions of this rule.
    APA, FedEx ALPA, SWAPA, CAPA, and Flight Time ARC said that the
definition of ``rest facility'' should include the following
clarification: ``A rest facility on an aircraft shall only be used for
in-flight rest opportunities.'' The commenters said this statement will
eliminate any temptation to have crews obtaining their part Sec.
117.25 or part Sec.  117.17 rest on the aircraft when it is on the
ramp. Several of these commenters noted that a bunk or seat on an
aircraft is not a suitable rest facility on the ground. APA further
recommended that the FAA separate the definitions of an ``in-flight,
onboard rest facility'' and a ``ground-based rest facility'' and
clearly differentiate between a ground-based rest facility and a
suitable accommodation.
    The FAA agrees with the above commenters that rest in a rest
facility should take place while an aircraft is in-flight. That is why
the augmented FDP section, section 117.17, to which the rest-facilities
definition applies, mandates that the required minimum augmentation
rest take place in-flight. Because section 117.17 already requires that
the minimum augmentation rest take place in-flight, there is no need to
further amend the pertinent regulatory text.
    Turning to APA's request for clarification concerning the
distinction between onboard and ground-based rest facilities, the FAA
notes that a rest facility is a facility that is installed in an
aircraft. A suitable accommodation, on the other hand, is a ground-
based facility. The FAA has amended the pertinent definitions to
clarify this distinction between a suitable accommodation and a rest
facility.
    APA also stated that detailed minimum standards should be spelled
out in regulatory requirements. At a minimum, the language in the Class
1 facility definition should be improved to indicate that other
surfaces that allow for a flat sleeping position should be suitably
padded and reasonably comfortable and suitable for sleeping. APA noted
that the ARC's discussions described ground-based facilities primarily
as bunkrooms and the like used by cargo carriers to provide rest during
a package sort operation. APA urged the FAA to adopt the detailed
recommendations regarding onboard rest facility requirements set out in
the appendix included in its comment submission. APA added that it
remains concerned that if such specifications are left to Advisory
Circulars, and if important details are not followed, in-flight rest
could be seriously compromised. Additionally, it noted that several
studies have commented on sleep problems caused by low humidity or an
improper temperature, but the FAA did not mention these factors nor
list any requirement for them. APA suggested that a Class 1 rest
facility should account for low humidity and improper temperatures.
    Delta expressed concern with the following description of a Class 2
facility that, it said, is contained both in the preface and in
Advisory Circular 121-31A: A Class 2 rest facility is ``a seat in an
aircraft cabin that allows for a flat or near flat sleeping position
(around 80 degrees from the seat's vertical centerline).'' Delta said
that many U.S. carriers currently providing on board rest facilities on
routes for which Class 2 seats would be used are using a passenger
business class type seat, some of which have been slightly modified or
enhanced. The commenter further noted that these types of facilities
have been in use for many years mostly on flights governed by 14 CFR
121.483. According to Delta, the ARC discussed this issue and
acknowledged that these existing seats have worked very well. Delta
asserted that most of these seats do not recline to the 80 degree range
nor is it known yet if it is feasible to modify them for this
capability. Delta believed that business class type seats currently
being used are more than adequate to allow for in-flight rest.
    UPS and NACA said that the definition of a Class 2 rest facility
fails to address rest facilities on aircraft configured without a
passenger cabin (i.e., all-cargo aircraft). UPS suggested that the
definition should read: ``In an aircraft configured with a passenger
cabin, Class 2 rest facility means a seat that allows for a flat or
near flat sleeping position and is separated from passengers by a
minimum of a curtain to provide darkness and some sound mitigation, and
is reasonably free from disturbance by passengers or in-flight
flightcrew members. In an aircraft not configured with a passenger
cabin, Class 2 rest facility means a seat that allows for a flat or
near flat sleeping position.''
    In response to these comments, the FAA notes that, as discussed
above, the specific requirements for rest facilities were derived from
the TNO Report, which analyzed how much rest would be obtained from
each rest facility that complied with those requirements. Because
various air carriers currently utilize different types of rest
facilities, the FAA has determined that adding to the TNO Report's
minimum rest-facility requirements would require more air carriers to
replace their existing rest facilities without a demonstrated safety
benefit to justify this cost. Accordingly, the FAA declines to add
additional requirements to the rest-facility requirements set out in
the NPRM.
    The FAA has also decided not to expand the definition of a Class 2
rest facility beyond the recommendations of the TNO Report. The FAA is
open to the possibility of expanding the definition of a Class 2 rest
facility if additional data is provided as part of an FRMS, and if
expanding this definition would not adversely affect safety. In
response

to UPS and NACA's concerns, the FAA has changed the phrase ``passenger
cabin'' to ``aircraft cabin'' in the rest-facility definition in order
to include rest facilities on aircraft without a passenger cabin.
    A number of industry groups and air carriers also objected to the
fact that the NPRM did not consider economy-class seats to be a rest
facility. These commenters stated that, in their operational
experience, economy-class seats provided flightcrew members with
significant amounts of restful sleep. The commenters cited a number of
studies that, they claimed, indicate that an economy-class seat can
provide restful sleep.
    The decision to not consider an economy-class seat to be a rest
facility was based on the TNO Report, which determined that ``the
probability of obtaining recuperative sleep in such a seat would be
minimal.'' \19\ The TNO Report's determination was based on the
following considerations: (1) An economy-class seat does not recline
more than 40 degrees ``and has no opportunities for adequate foot and
leg rest, which diminishes the probability of recuperative sleep;'' (2)
``space around the seat is not sufficient to create an adequate
separation from the passengers (jostle in economy class), or guarantee
any privacy;'' and (3) ``a majority of passengers are unable to sleep
at all in an economy seat. With the help of sleeping aids or alcohol,
some passengers succeed in obtaining some sleep, but they often feel a
general malaise after sleeping in a cramped position.'' \20\ The FAA
agrees with the TNO Report's analysis of economy-class seats, and based
on this analysis, which states that economy-class seats provide minimal
amounts of recuperative sleep, the FAA has determined that economy-
class seats should not be considered a rest facility in this rule.
---------------------------------------------------------------------------

    \19\ TNO Report at 17.
    \20\ Id. at 18.
---------------------------------------------------------------------------

    Delta stated that it is unclear why the FAA is concerned with
keeping crew rest facilities out of the coach or economy section of the
aircraft. Delta believes that if the seat meets the NPRM definition
requirements and the specifications provided in AC 121-3A (now AC 117-
1), the geographical location of the rest facility on the aircraft
should be immaterial. Delta further noted that it attempted to locate a
scientific or an operational basis for the exclusionary requirement and
has been unable to find any; therefore, Delta believes this is an
unjustified constraint and should be removed.
    As discussed in the preceding response, one of the reasons why an
economy-class seat does not provide restful sleep is that space around
the seat is not sufficient to create an adequate separation from the
passengers (economy jostling). Because there are substantially more
passengers in the economy section of an aircraft, that section is
generally noisier and has more densely-packed people than the other
sections of the aircraft. In addition, the FAA notes that economy
cabins are generally located behind the aircraft engines, and thus,
have to deal with louder engine noise. Due to all of these
considerations, locating a rest facility in the economy section would
reduce the restfulness of the sleep obtained by a flightcrew member.
    Boeing stated it has concerns about the use of the phrase ``sleep
opportunity'' in the definition. It noted that it considers a ``sleep
opportunity'' to be a period of time during which sleep or rest can
feasibly occur. Boeing suggested that the definition be revised to
read: ``Rest facility means a bunk, seat, room, or other accommodation
that provides a flightcrew member with comfort and quiet so as to
maximize sleep and rest within a sleep opportunity period.''
    Boeing's suggested definition of rest facilities has already been
largely incorporated into the definitions for the Class 1 and 2 rest
facilities. The FAA declines to incorporate the suggested definition
for a Class 3 rest facility because there is no recommendation in the
TNO Report that a Class 3 facility provide sound mitigation.
    Boeing also said that it finds the new crew rest definitions to be
overly prescriptive, and may drive design and configuration decisions
that would run counter to the intent of the proposed rule. For example,
all three classes of rest facility are defined by their location: Class
1 must be located ``separate from both the flight deck and passenger
cabin;'' Class 2 must be in the passenger cabin; and Class 3 must be in
the cabin or flight deck. Boeing notes that while these definitions may
encompass most or many of the current airplane configurations, they
preclude new and novel designs that might better match the intent of
the rule. The commenter recommended that the FAA consider including a
provision in the rule that would allow new or alternative designs to be
qualified as ``equivalent'' to Class 1, 2, or 3, based on scientific
data, such as: ``Rest facilities may be qualified to a higher Class if
the quantity of sleep achieved in the facility can be demonstrated to
be equal to or greater than the level achieved by that Class.''
    Boeing's recommendation for recognizing new rest facilities that
provide a sleep opportunity that is equivalent to the rest facilities
defined by this rule is addressed by the FRMS and exemption processes.
If an air carrier can show that its rest facility provides the same
benefits as a Class 1, 2, or 3 rest facility, the FAA may approve an
FRMS or an exemption recognizing the rest facility in question as
providing the same fatigue mitigation as the rest facilities regulated
by this rule.
    Atlas said that the proposed rule's definition of rest facility is
unworkably vague and leaves a number of uncertainties, which the FAA
declined to clarify in response to questions. In particular, NACA and
Atlas stated that the definition of Class 1 rest facility needs to be
revised, as it is impossible to provide complete ``isolation from noise
and disturbance'' on an aircraft. Atlas said that it supports changing
the definition of a Class 3 rest facility to include a common coach
class seat or non-crew seat on the flight deck of an all-cargo
aircraft.
    The definition for a Class 1 rest facility does not require that
the isolation from noise and disturbance be complete. The FAA will
accept a Class 1 rest facility that minimizes noise and disturbance
without eliminating it completely, as complete elimination of noise and
disturbance onboard an aircraft is virtually impossible. As discussed
above, the FAA has declined to accept an economy-class seat as a rest
facility because the TNO Report has determined that these types of seat
provide a minimal amount of restful sleep.
24. Rest Period
    The NPRM defined ``rest period'' as a continuous period determined
prospectively during which the flightcrew member is free from all
restraint by the certificate holder, including freedom from present
responsibility for work should the occasion arise. None of the comments
raised any significant issues with regard to this definition, and as
such, this rule adopts the proposed definition.
25. Scheduled
    The NPRM stated that ``scheduled'' means times assigned by a
certificate holder when a flightcrew member is required to report for
duty.
    UPS commented that the definition does not address reschedules that
occur during an FDP but only schedules assigned when the flightcrew
member

reported for duty. UPS suggested revising the definition as follows:
``Scheduled means times assigned by a certificate holder when a
flightcrew member is required to report for duty or has been given a
re-schedule during the FDP that fully complies with the requirements of
this part.''
    The FAA agrees with UPS that the proposed definition was ambiguous.
The pertinent definition has been amended for clarification purposes.
26. Schedule Reliability
    The NPRM defines ``schedule reliability'' to mean the accuracy of
the length of a scheduled flight duty period as compared to the actual
flight duty period.
    FedEx ALPA, ALPA, CAPA, SWAPA, IPA, and Flight Time ARC proposed
the following revised definition for schedule reliability: ``Schedule
reliability means the accuracy of the length of both a scheduled flight
duty period and a scheduled flight segment as compared to the actual
flight duty period and segment.'' SWAPA offered the following rationale
for the revised definition: ``To achieve schedule reliability, the
individual flight segments must be considered. If a given segment
within a pairing causes the pairing to exceed the limits, the
certificate holder can merely leave the offending segment and change
the pairing mix to bring it within limits. The segment would never be
corrected. We believe that a scheduling metric must be included in
Sec.  117.9. Certificate holders now provide on-time reports to the DOT
on an individual flight segment so this should not be a burdensome
requirement.''
    UPS said that defining schedule reliability as a comparison of an
actual FDP to a scheduled FDP has no fatigue or safety implications. It
recommended revising the definition as follows to match the preamble
description: ``Schedule reliability means the accuracy of the length of
a scheduled flight duty period as compared to the maximum FDP listed in
either Tables B or C (as applicable).''
    As discussed in other parts of this preamble, the FAA has largely
removed the proposed schedule-reliability requirements from the final
rule. As such, there is no longer a need to define schedule
reliability, and that definition has been removed from this rule.
27. Short-Call Reserve
    The NPRM stated that ``short-call reserve'' means a period of time
in which a flightcrew member does not receive a required rest period
following notification by the certificate holder to report for a flight
duty period.
    NACA said that the only task assigned during short-call reserve is
answering the phone. Otherwise, flightcrew members are free to conduct
their lives as if they were in a rest period. NACA recommended
clarifying the definition by specifying that short-call reserve is not
duty.
    NACA, Atlas, and NAA asked the FAA to more clearly distinguish
short-call reserve from airport/standby reserve. Atlas recommended
revising the definition of short-call reserve to mean ``a short,
designated period of time (usually three hours or less), either at home
or in a hotel, during which a flightcrew member is on reserve call-up
for an assignment. Because the flightcrew member has not reported for
assignment and rest is available, the time on short-call reserve is not
to be considered part of FDP or duty.'' NAA recommended the following
revision to the definition to address its concerns: ``Short-call
reserve means a period of duty time in which a flightcrew member does
not receive a required rest period following notification by the
certificate holder to report for a flight duty period, but is provided
more than one hour notice of the required reporting time.''
    In response to the above comments, the FAA notes that the
distinctive feature of short-call reserve is that the flightcrew member
on short-call reserve is assigned a reserve availability period.
Accordingly, the definition of short-call reserve has been amended to
clarify that this definition only applies to a flightcrew member who is
assigned to a reserve availability period. As discussed in the
pertinent portions of this preamble, the FAA has removed the
cumulative-duty-period limits from this rule, in part, in response to
concerns raised by commenters about the way that this cumulative limit
impacted short-call reserve.
28. Split Duty
    The NPRM defines ``split duty'' as a flight duty period that has a
scheduled break in duty that is less than a required rest period.
    NACA said that the definition of split duty should make clear that
the term ``scheduled'' is used only where it is clearly applicable to
the situation intended. For non-scheduled operations, NACA believed
that a schedule begins when the flightcrew member shows up for an FDP.
As such, NACA argued that split-duty credit should be provided for a
break in nonscheduled operations that was not foreseen. Additionally,
according to NACA, a scheduled split duty break should not be strictly
enforced because it may be intended in a nonscheduled FDP at the time
the flightcrew member shows up for the FDP but not used for real-time
operational reasons.
    NACA further said that the fatigue-mitigating rest must be provided
in the FDP in which the split-duty credit is actually used. According
to NACA, the split-duty rest can only be used if the split duty rest
opportunity is actually provided. NACA recommended that the definition
be revised as follows, to include the phrase ``an actual'' to address
its concerns: ``split duty means a flight duty period that has an
actual scheduled break in duty that is less than a required rest