(c)..................................  .......................  23.2605................  Installation and
                                                                                operation.
(d)..................................  .......................  23.2300 and 23.2600....  Flight control systems;
                                                                                Flightcrew interface.
(e), (f), (g)........................  .......................  23.2500 and 23.2510....  Airplane level systems
                                                                                requirements;
                                                                                Equipment, systems,
                                                                                and installations.
(h)..................................  .......................  23.2605................  Installation and
                                                                                operation.
23.1331..............................  Instruments using a
                                        power source.
(a)..................................  .......................  23.2605................  Installation and
                                                                                operation.
(b) and (c)..........................  .......................  23.2510 and 23.2525....  Equipment, systems, and
                                                                                installations; System
                                                                                power generation,
                                                                                storage, and
                                                                                distribution.
23.1335..............................  Flight director systems  23.2500, 23.2505,        Airplane level systems;
                                                                 23.2510, 23.2600, and    Function and
                                                                 23.2605.                 installation;
                                                                                Equipment systems and
                                                                                installations;
                                                                                Flightcrew interface;
                                                                                and Installation and
                                                                                operation.
23.1337..............................  Powerplant instruments
                                        installation.
(a)..................................  .......................  23.2325................  Fire protection.
                                                                23.2430................  Fuel systems.
(b)..................................  .......................  23.2605................  Installation and
                                                                                operation.
                                                                23.2610................  Flight, navigation, and
                                                                                powerplant
                                                                                instruments.
                                                                23.2510................  Equipment, systems, and
                                                                                installations.
(c)..................................  .......................  23.2510................  Equipment, systems, and
                                                                                installations.
(d)..................................  .......................  23.2605................  Installation and
                                                                                operation.
                                                                23.2615................  Flight, navigation, and
                                                                                powerplant
                                                                                instruments.
23.1351..............................  Electrical Systems--
                                        General.
(a)..................................  .......................  23.2525................  System power
                                                                                generation, storage,
                                                                                and distribution.
(b)..................................  .......................  23.2500, 23.2525.......  Airplane level systems
                                                                                requirements: System
                                                                                power generation,
                                                                                storage, and
                                                                                distribution.
(c)..................................  .......................  23.2525, 23.2605.......  System power
                                                                                generation, storage,
                                                                                and distribution;
                                                                                Installation and
                                                                                operation.
(d)..................................  .......................  23.2605................  Installation and
                                                                                operation.
(e)..................................  .......................  23.2500, 23.2325.......  Airplane level systems
                                                                                requirements: Fire
                                                                                protection.
(f), (g).............................  .......................  23.2500................  Airplane level systems
                                                                                requirements.
23.1353..............................  Storage battery design   23.2525................  System power
                                        and installation.                                 generation, storage,
                                                                                and distribution.

23.1357..............................  Circuit protective       23.2500, 23.2505,        Airplane level systems
                                        devices.                 23.2510, and 23.2525.    requirements; Function
                                                                                and installation;
                                                                                Equipment, systems,
                                                                                and installations; and
                                                                                System power
                                                                                generation, storage,
                                                                                and distribution.
23.1359..............................  Electrical system fire
                                        protection.
(a)..................................  .......................  23.2330, 23.2325.......  Fire protection in
                                                                                designated fire zones;
                                                                                Fire protection.
(b)..................................  .......................  23.2330................  Fire protection in
                                                                                designated fire zones.
(c)..................................  .......................  23.2325................  Fire protection.
23.1361..............................  Master switch            23.2500 and 23.2505....  Airplane level systems
                                        arrangement.                                      requirements; Function
                                                                                and installation.
23.1365..............................  Electrical cables and    23.2505................  Function and
                                        equipment.                                        installation.
(b)..................................  .......................  23.2330................  Fire protection in
                                                                                designated fire zones.
23.1367..............................  Switches...............
(a) and (b)..........................  .......................  23.2505................  Function and
                                                                                installation.
(c) and (d)..........................  .......................  23.2600................  Flightcrew interface.
23.1381..............................  Instrument lights......
(a) and (b)..........................  .......................  23.2600................  Flightcrew interface.
(c)..................................  .......................  23.2500................  Airplane level systems
                                                                                requirements.
23.1383(a), (b), (c).................  Taxi and landing lights  23.2530................  External and cockpit
                                                                                lighting.
(d)..................................  Taxi and landing lights  23.2325................  Fire protection.
23.1385(a), (b), (c).................  Position light system    23.2530................  External and cockpit
                                        installation.                                     lighting.
(d)..................................  Position light system    23.2325................  Fire protection.
                                        installation.
23.1387..............................  Position light system    23.2530................  External and cockpit
                                        dihedral angles.                                  lighting.
23.1389..............................  Position light           23.2530................  External and cockpit
                                        distribution and                                  lighting.
                                        intensities.
23.1391..............................  Minimum intensities in   23.2530................  External and cockpit
                                        the horizontal plane                              lighting.
                                        of position lights.
23.1393..............................  Minimum intensities in   23.2530................  External and cockpit
                                        any vertical plane of                             lighting.
                                        position lights.
23.1395..............................  Maximum intensities in   23.2530................  External and cockpit
                                        overlapping beams of                              lighting.
                                        position lights.
23.1397..............................  Color specifications...  23.2530................  External and cockpit
                                                                                lighting.
23.1399..............................  Riding light...........  23.2530................  External and cockpit
                                                                                lighting.
23.1401..............................  Anticollision light
                                        system.
(a), (a)(1)..........................  .......................  23.2530................  External and cockpit
                                                                                lighting.
(a)(2)...............................  .......................  Means Of Compliance....
(b) thru (f).........................  .......................  23.2530................  External and cockpit
                                                                                lighting.
23.1411..............................  Safety Equipment-
                                        General.
(a), (b)(1)..........................  .......................  23.2535................  Safety equipment.
(b)(2)...............................  .......................  23.2270................  Emergency conditions.
23.1415..............................  Ditching equipment.....  23.2535................  Safety equipment.
(a), (c), (d)........................  .......................  23.2535................  Safety equipment.
(b)..................................  .......................  Means Of Compliance....
23.1416..............................  Pneumatic de-icer boot   23.2500................  Airplane level systems
                                        system.                                           requirements.
                                                                23.2505................  Function and
                                                                                installation.
(c)..................................  .......................  23.2605(b).............  Installation and
                                                                                operation.
23.1419..............................  Ice protection.........  23.2165(a)(1)..........  Performance and flight
                                                                                characteristics
                                                                                requirements for
                                                                                flight in icing
                                                                                conditions.
                                                                23.2540(a).............  Flight in icing
                                                                                conditions.
(d)..................................  .......................  23.2600(a).............  Flightcrew interface.
23.1431..............................  Electronic equipment...  23.2510................  Equipment, systems and
                                                                                installations.
23.1435..............................  Hydraulic systems......
(a)(1)...............................  .......................  23.2235................  Structural strength.
(a)(2)...............................  .......................  23.2600................  Flightcrew interface.
(a)(3)(c)............................  .......................  23.2250................  Design and construction
                                                                                principles.
(a)(4), (b)..........................  .......................  23.2545................  Pressurized system
                                                                                elements.
(c)..................................  .......................  23.2440(c).............  Powerplant fire
                                                                                protection.
23.1437..............................  Accessories for          23.2410 & 23.2515......  Powerplant installation
                                        multiengine airplanes.                            hazard assessment and
                                                                                Equipment, systems and
                                                                                installations.
23.1438..............................  Pressurization and       23.2545................  Pressurized system
                                        pneumatic systems.                                elements.

23.1441..............................  Oxygen equipment and     23.2320(e).............  Occupant physical
                                        supply.                                           environment.
(c)..................................  .......................  23.2605(b).............  Installation and
                                                                                operation.
23.1443..............................  Minimum mass flow of     23.2320(e).............  Occupant physical
                                        supplemental oxygen.                              environment.
23.1445..............................  Oxygen distribution      23.2320(e).............  Occupant physical
                                        system.                                           environment.
(a), (b).............................  .......................  23.2250(c).............  Design and construction
                                                                                principles.
23.1447..............................  Equipment standards for  23.2320(e).............  Occupant physical
                                        oxygen dispensing                                 environment.
                                        units.
23.1449..............................  Means for determining    23.2320(e).............  Occupant physical
                                        use of oxygen.                                    environment.
23.1450..............................  Chemical oxygen
                                        generators.
(a)(b)...............................  .......................  23.2320(e).............  Occupant physical
                                                                                environment.
(c)..................................  .......................  23.2610................  Instrument markings,
                                                                                control markings, and
                                                                                placards.
23.1451..............................  Fire protection for      23.2320(e).............  Occupant physical
                                        oxygen equipment.                                 environment.
23.1453..............................  Protection of oxygen     23.2320(e) & 23.2545...  Occupant physical
                                        equipment from rupture.                           environment &
                                                                                Pressurized system
                                                                                elements.
23.1457..............................  Cockpit voice recorders  23.1457................  No Change.
23.1459..............................  Flight recorders.......  23.1459................  No Change.
23.1461..............................  Equipment containing     23.2550................  Equipment containing
                                        high-energy rotors.                               high-energy rotors.
----------------------------------------------------------------------------------------------------------------
                                Subpart G--Operating Limitations and Information
----------------------------------------------------------------------------------------------------------------
23.1501..............................  General................  23.2610................  Instrument, control
                                                                                markings, and
                                                                                placards.
23.1505..............................  Airspeed limitations...  23.2610................  Instrument markings,
                                                                                control markings, and
                                                                                placards.
23.1507..............................  Operating maneuvering    23.2610................  Instrument markings,
                                        speed.                                            control markings, and
                                                                                placards.
23.1511..............................  Flap extended speed....  23.2610................  Instrument markings,
                                                                                control markings, and
                                                                                placards.
23.1513..............................  Minimum control speed..  23.2610................  Instrument markings,
                                                                                control markings, and
                                                                                placards.
23.1519..............................  Weight and center of     23.2610................  Instrument markings,
                                        gravity.                                          control markings, and
                                                                                placards.
23.1521..............................  Powerplant limitations.  23.2610................  Instrument markings,
                                                                                control markings, and
                                                                                placards.
23.1522..............................  Auxiliary power unit     23.2610................  Instrument markings,
                                        limitations.                                      control markings, and
                                                                                placards.
23.1523..............................  Minimum flight crew....  23.2610................  Instrument markings,
                                                                                control markings, and
                                                                                placards.
23.1524..............................  Maximum passenger        23.2610................  Instrument markings,
                                        seating configuration.                            control markings, and
                                                                                placards.
23.1525..............................  Kinds of operation.....  23.2610................  Airplane level system
                                                                                requirements.
                                                                23.2610................  Instrument markings,
                                                                                control markings, and
                                                                                placards.
23.1527..............................  Maximum operating        23.2610................  Instrument markings,
                                        altitude.                                         control markings, and
                                                                                placards.
23.1529..............................  Instructions for         23.1529................  Instructions for
                                        continued                                         continued
                                        airworthiness.                                    airworthiness.
23.1541..............................  Marking and Placards--   23.2610................  Instrument markings,
                                        General.                                          control markings, and
                                                                                placards.
23.1543..............................  Instrument marking:      23.2610................  Instrument markings,
                                        General.                                          control markings, and
                                                                                placards.
23.1545..............................  Airspeed indicator.....  23.2610................  Instrument markings,
                                                                                control markings, and
                                                                                placards.
23.1547..............................  Magnetic direction       23.2610................  Instrument markings,
                                        indicator.                                        control markings, and
                                                                                placards.
23.1549..............................  Powerplant and           23.2610................  Instrument markings,
                                        auxiliary power unit                              control markings, and
                                        instruments.                                      placards.
23.1551..............................  Oil quantity indicator.  23.2610................  Instrument markings,
                                                                                control markings, and
                                                                                placards.
23.1553..............................  Fuel quantity indicator  23.2610................  Instrument markings,
                                                                                control markings, and
                                                                                placards.
23.1555..............................  Control markings.......  23.2610................  Instrument markings,
                                                                                control markings, and
                                                                                placards.
23.1557..............................  Miscellaneous marking    23.2610................  Instrument markings,
                                        and placards.                                     control markings, and
                                                                                placards.
23.1559..............................  Operating limitations    23.2610................  Instrument markings,
                                        placard.                                          control markings, and
                                                                                placards.

23.1561..............................  Safety equipment.......  23.2610................  Instrument markings,
                                                                                control markings, and
                                                                                placards.
23.1563..............................  Airspeed placards......  23.2610................  Instrument markings,
                                                                                control markings, and
                                                                                placards.
23.1567..............................  Flight maneuver placard  23.2610................  Instrument markings,
                                                                                control markings, and
                                                                                placards.
23.1581..............................  Airplane Flight Manual   23.2620................  Airplane flight manual.
                                        and Approved Manual
                                        Material--General.
23.1583..............................  Operating limitations..  23.2620................  Airplane flight manual.
23.1585..............................  Operating procedures...  23.2620................  Airplane flight manual.
23.1587..............................  Performance information  23.2620................  Airplane flight manual.
23.1589..............................  Loading information....  23.2620................  Airplane flight manual.
Appendix A...........................  Simplified Design Load   Means Of Compliance....
                                        Criteria.
Appendix B...........................  [Reserved].............
Appendix C...........................  Basic Landing            Means Of Compliance....
                                        Conditions.
Appendix D...........................  Wheel Spin-Up and        Means Of Compliance....
                                        Spring-Back Loads.
Appendix E...........................  [Reserved].............
Appendix F...........................  Test Procedure.........  Means Of Compliance....
Appendix G...........................  Instructions for         Appendix A.............  Instructions for
                                        Continued                                         Continued
                                        Airworthiness.                                    Airworthiness.
Appendix H...........................  Installation of An       Means Of Compliance....
                                        Automatic Power
                                        Reserve (APR) System.
Appendix I...........................  Seaplane Loads.........  Means Of Compliance....
Appendix J...........................  HIRF Environments and    Means Of Compliance....
                                        Equipment HIRF Test
                                        Levels.
----------------------------------------------------------------------------------------------------------------

Appendix 2 to the Preamble--Abbreviations and Acronyms Frequently Used
in This Document

AC Advisory Circular
AD Airworthiness Directive
AFM Airplane Flight Manual
A-NPA Advance Notice of Proposed Amendment
ARC Aviation Rulemaking Committee
ASTM ASTM International
FCAA Foreign Civil Aviation Authority
CAR 3 Civil Aviation Regulations, Part 3
Cf Confer (to identify a source or a usage citation for a word or
phrase)
CPS Certification Process Study
CS Certification Specification
CS-VLA Certification Specification-Very Light Aeroplanes
DER Designated Engineering Representative
EASA European Aviation Safety Agency
ELOS Equivalent Level of Safety
FR Federal Register
GA General Aviation
HIRF High-Intensity Radiated Field
IFR Instrument Flight Rules
IMC Instrument Meteorological Conditions
KCAS Knots Calibrated Airspeeds
LOC Loss of Control
NATCA National Air Traffic Controllers Association
NPA Notice of Proposed Amendment
NPRM Notice of Proposed Rulemaking
NTSB National Transportation Safety Board
OMB Office of Management and Budget
SAE SAE International
SARA Small Airplane Revitalization Act of 2013
SLD Supercooled Large Droplet
STC Supplemental Type Certificate
TC Type Certificate
TCDS Type Certificate Data Sheet
VA Design Maneuvering Speed
VC Design Cruising Speed
VD Design Dive Speed
VMC Minimum Control Speed
VMO/MMO Maximum Operating Limit Speed
VNO Maximum Structural Cruising Speed
VFR Visual Flight Rules
VSO Stalling speed or the minimum steady flight speed in
the landing configuration

List of Subjects

14 CFR Part 21

    Aircraft, Aviation safety, Recording and recordkeeping
requirements.

14 CFR Part 23

    Aircraft, Aviation Safety, Signs and symbols.

14 CFR Part 35

    Aircraft, Aviation safety.

14 CFR Part 43

    Aircraft, Aviation safety, Reporting and recordkeeping
requirements.

14 CFR Part 91

    Air traffic control, Aircraft, Airmen, Airports, Aviation safety,
Reporting and recordkeeping requirements.

14 CFR Part 121

    Aircraft, Airmen, Aviation safety, Reporting and recordkeeping
requirements.

14 CFR Part 135

    Aircraft, Airmen, Aviation safety, Reporting and recordkeeping
requirements.

The Amendment

    In consideration of the foregoing, the Federal Aviation
Administration amends chapter I of title 14, Code of Federal
Regulations as follows:

PART 21--CERTIFICATION PROCEDURES FOR PRODUCTS AND ARTICLES

0
1. The authority citation for part 21 is revised to read as follows:

    Authority:  42 U.S.C. 7572; 49 U.S.C. 106(f), 106(g), 40105,
40113, 44701-44702, 44704, 44707, 44709, 44711, 44713, 44715, 45303.

0
2. In Sec.  21.9, revise paragraphs (a)(5), (a)(6), and add paragraph
(a)(7) to read as follows:

Sec.  21.9   Replacement and modification articles.

    (a) * * *
    (5) Produced by an owner or operator for maintaining or altering
that owner or operator's product;
    (6) Fabricated by an appropriately rated certificate holder with a
quality system, and consumed in the repair or alteration of a product
or article in accordance with part 43 of this chapter; or
    (7) Produced in any other manner approved by the FAA.
* * * * *

0
3. In Sec.  21.17, revise paragraph (a) introductory text to read as
follows:

Sec.  21.17   Designation of applicable regulations.

    (a) Except as provided in Sec. Sec.  25.2, 27.2, 29.2, and in parts
26, 34, and 36 of this subchapter, an applicant for a type certificate
must show that the aircraft, aircraft engine, or propeller concerned
meets--
* * * * *

0
4. In Sec.  21.24, revise paragraph (a)(1)(i) to read as follows:

Sec.  21.24   Issuance of type certificate: primary category aircraft.

    (a) * * *
    (1) * * *
    (i) Is unpowered; is an airplane powered by a single, naturally
aspirated engine with a 61-knot or less Vso stall speed as
determined under part 23 of this chapter; or is a rotorcraft with a 6-
pound per square foot main rotor disc loading limitation, under sea
level standard day conditions;
* * * * *

0
5. In Sec.  21.35, revise paragraph (b)(2) to read as follows:

Sec.  21.35   Flight tests.

* * * * *
    (b) * * *
    (2) For aircraft to be certificated under this subchapter, except
gliders and low-speed, certification level 1 or 2 airplanes, as defined
in part 23 of this chapter, to determine whether there is reasonable
assurance that the aircraft, its components, and its equipment are
reliable and function properly.
* * * * *

0
6. In Sec.  21.50, revise paragraph (b) to read as follows:

Sec.  21.50   Instructions for continued airworthiness and
manufacturer's maintenance manuals having airworthiness limitations
sections.

* * * * *
    (b) The holder of a design approval, including either a type
certificate or supplemental type certificate for an aircraft, aircraft
engine, or propeller for which application was made after January 28,
1981, must furnish at least one set of complete Instructions for
Continued Airworthiness to the owner of each type aircraft, aircraft
engine, or propeller upon its delivery, or upon issuance of the first
standard airworthiness certificate for the affected aircraft, whichever
occurs later. The Instructions for Continued Airworthiness must be
prepared in accordance with Sec. Sec.  [thinsp]23.1529, 25.1529,
25.1729, 27.1529, 29.1529, 31.82, 33.4, 35.4, or part 26 of this
subchapter, or as specified in the applicable airworthiness criteria
for special classes of aircraft defined in Sec.  [thinsp]21.17(b), as
applicable. If the holder of a design approval chooses to designate
parts as commercial, it must include in the Instructions for Continued
Airworthiness a list of commercial parts submitted in accordance with
the provisions of paragraph (c) of this section. Thereafter, the holder
of a design approval must make those instructions available to any
other person required by this chapter to comply with any of the terms
of those instructions. In addition, changes to the Instructions for
Continued Airworthiness shall be made available to any person required
by this chapter to comply with any of those instructions.
* * * * *

0
7. In Sec.  21.101 revise paragraphs (b) introductory text, and (c) to
read as follows:

Sec.  21.101   Designation of applicable regulations.

* * * * *
    (b) Except as provided in paragraph (g) of this section, if
paragraphs (b)(1), (2), or (3) of this section apply, an applicant may
show that the change and areas affected by the change comply with an
earlier amendment of a regulation required by paragraph (a) of this
section, and of any other regulation the FAA finds is directly related.
However, the earlier amended regulation may not precede either the
corresponding regulation included by reference in the type certificate,
or any regulation in Sec. Sec.  25.2, 27.2, or 29.2 of this chapter
that is related to the change. The applicant may show compliance with
an earlier amendment of a regulation for any of the following:
* * * * *
    (c) An applicant for a change to an aircraft (other than a
rotorcraft) of 6,000 pounds or less maximum weight, to a non-turbine
rotorcraft of 3,000 pounds or less maximum weight, to a level 1 low-
speed airplane, or to a level 2 low-speed airplane may show that the
change and areas affected by the change comply with the regulations
included in the type certificate. However, if the FAA finds that the
change is significant in an area, the FAA may designate compliance with
an amendment to the regulation incorporated by reference in the type
certificate that applies to the change and any regulation that the FAA
finds is directly related, unless the FAA also finds that compliance
with that amendment or regulation would not contribute materially to
the level of safety of the product or would be impractical.
* * * * *

0
8. Revise part 23 to read as follows:

PART 23--AIRWORTHINESS STANDARDS: NORMAL CATEGORY AIRPLANES

Sec.
23.1457 Cockpit voice recorders.
23.1459 Flight data recorders.
23.1529 Instructions for continued airworthiness.
Subpart A--General
23.2000 Applicability and definitions.
23.2005 Certification of normal category airplanes.
23.2010 Accepted means of compliance.
Subpart B--Flight

Performance

23.2100 Weight and center of gravity.
23.2105 Performance data.
23.2110 Stall speed.
23.2115 Takeoff performance.
23.2120 Climb requirements.
23.2125 Climb information.
23.2130 Landing.

Flight Characteristics

23.2135 Controllability.
23.2140 Trim.
23.2145 Stability.
23.2150 Stall characteristics, stall warning, and spins.
23.2155 Ground and water handling characteristics.
23.2160 Vibration, buffeting, and high-speed characteristics.
23.2165 Performance and flight characteristics requirements for
flight in icing conditions.
Subpart C--Structures
23.2200 Structural design envelope.
23.2205 Interaction of systems and structures.

Structural Loads

23.2210 Structural design loads.
23.2215 Flight load conditions.
23.2220 Ground and water load conditions.
23.2225 Component loading conditions.
23.2230 Limit and ultimate loads.

Structural Performance

23.2235 Structural strength.
23.2240 Structural durability.
23.2245 Aeroelasticity.

Design

23.2250 Design and construction principles.
23.2255 Protection of structure.
23.2260 Materials and processes.
23.2265 Special factors of safety.

Structural Occupant Protection

23.2270 Emergency conditions.
Subpart D--Design and Construction
23.2300 Flight control systems.
23.2305 Landing gear systems.
23.2310 Buoyancy for seaplanes and amphibians.

Occupant System Design Protection

23.2315 Means of egress and emergency exits.
23.2320 Occupant physical environment.

Fire and High Energy Protection

23.2325 Fire protection.
23.2330 Fire protection in designated fire zones and adjacent areas.
23.2335 Lightning protection.
Subpart E--Powerplant
23.2400 Powerplant installation.
23.2405 Automatic power or thrust control systems.
23.2410 Powerplant installation hazard assessment.
23.2415 Powerplant ice protection.
23.2420 Reversing systems.
23.2425 Powerplant operational characteristics.
23.2430 Fuel system.
23.2435 Powerplant induction and exhaust systems.
23.2440 Powerplant fire protection.
Subpart F--Equipment
23.2500 Airplane level systems requirements.
23.2505 Function and installation.
23.2510 Equipment, systems, and installations.
23.2515 Electrical and electronic system lightning protection.
23.2520 High-intensity Radiated Fields (HIRF) protection.
23.2525 System power generation, storage, and distribution.
23.2530 External and cockpit lighting.
23.2535 Safety equipment.
23.2540 Flight in icing conditions.
23.2545 Pressurized system elements.
23.2550 Equipment containing high-energy rotors.
Subpart G--Flightcrew Interface and Other Information
23.2600 Flightcrew interface.
23.2605 Installation and operation.
23.2610 Instrument markings, control markings, and placards.
23.2615 Flight, navigation, and powerplant instruments.
23.2620 Airplane flight manual.

Appendix A to Part 23--Instructions for Continued Airworthiness

    Authority:  49 U.S.C. 106(f), 106(g), 40113, 44701-44702, 44704,
Pub. L. 113-53, 127 Stat. 584 (49 U.S.C. 44704) note.

Sec.  23.1457   Cockpit voice recorders.

    (a) Each cockpit voice recorder required by the operating rules of
this chapter must be approved and must be installed so that it will
record the following:
    (1) Voice communications transmitted from or received in the
airplane by radio.
    (2) Voice communications of flightcrew members on the flight deck.
    (3) Voice communications of flightcrew members on the flight deck,
using the airplane's interphone system.
    (4) Voice or audio signals identifying navigation or approach aids
introduced into a headset or speaker.
    (5) Voice communications of flightcrew members using the passenger
loudspeaker system, if there is such a system and if the fourth channel
is available in accordance with the requirements of paragraph
(c)(4)(ii) of this section.
    (6) If datalink communication equipment is installed, all datalink
communications, using an approved data message set. Datalink messages
must be recorded as the output signal from the communications unit that
translates the signal into usable data.
    (b) The recording requirements of paragraph (a)(2) of this section
must be met by installing a cockpit-mounted area microphone, located in
the best position for recording voice communications originating at the
first and second pilot stations and voice communications of other
crewmembers on the flight deck when directed to those stations. The
microphone must be so located and, if necessary, the preamplifiers and
filters of the recorder must be so adjusted or supplemented, so that
the intelligibility of the recorded communications is as high as
practicable when recorded under flight cockpit noise conditions and
played back. Repeated aural or visual playback of the record may be
used in evaluating intelligibility.
    (c) Each cockpit voice recorder must be installed so that the part
of the communication or audio signals specified in paragraph (a) of
this section obtained from each of the following sources is recorded on
a separate channel:
    (1) For the first channel, from each boom, mask, or handheld
microphone, headset, or speaker used at the first pilot station.
    (2) For the second channel from each boom, mask, or handheld
microphone, headset, or speaker used at the second pilot station.
    (3) For the third channel--from the cockpit-mounted area
microphone.
    (4) For the fourth channel from:
    (i) Each boom, mask, or handheld microphone, headset, or speaker
used at the station for the third and fourth crewmembers.
    (ii) If the stations specified in paragraph (c)(4)(i) of this
section are not required or if the signal at such a station is picked
up by another channel, each microphone on the flight deck that is used
with the passenger loudspeaker system, if its signals are not picked up
by another channel.
    (5) And that as far as is practicable all sounds received by the
microphone listed in paragraphs (c)(1), (2), and (4) of this section
must be recorded without interruption irrespective of the position of
the interphone-transmitter key switch. The design shall ensure that
sidetone for the flightcrew is produced only when the interphone,
public address system, or radio transmitters are in use.
    (d) Each cockpit voice recorder must be installed so that:
    (1)(i) It receives its electrical power from the bus that provides
the maximum reliability for operation of the cockpit voice recorder
without jeopardizing service to essential or emergency loads.
    (ii) It remains powered for as long as possible without
jeopardizing emergency operation of the airplane.
    (2) There is an automatic means to simultaneously stop the recorder
and prevent each erasure feature from functioning, within 10 minutes
after crash impact.
    (3) There is an aural or visual means for preflight checking of the
recorder for proper operation.
    (4) Any single electrical failure external to the recorder does not
disable both the cockpit voice recorder and the flight data recorder.
    (5) It has an independent power source--
    (i) That provides 10 1 minutes of electrical power to
operate both the cockpit voice recorder and cockpit-mounted area
microphone;
    (ii) That is located as close as practicable to the cockpit voice
recorder; and
    (iii) To which the cockpit voice recorder and cockpit-mounted area
microphone are switched automatically in the event that all other power
to the cockpit voice recorder is interrupted either by normal shutdown
or by any other loss of power to the electrical power bus.
    (6) It is in a separate container from the flight data recorder
when both are required. If used to comply with only the cockpit voice
recorder requirements, a combination unit may be installed.
    (e) The recorder container must be located and mounted to minimize
the probability of rupture of the container as a result of crash impact
and consequent heat damage to the recorder from fire.
    (1) Except as provided in paragraph (e)(2) of this section, the
recorder container must be located as far aft as practicable, but need
not be outside of the pressurized compartment, and may not be located
where aft-mounted engines may crush the container during impact.
    (2) If two separate combination digital flight data recorder and
cockpit voice

recorder units are installed instead of one cockpit voice recorder and
one digital flight data recorder, the combination unit that is
installed to comply with the cockpit voice recorder requirements may be
located near the cockpit.
    (f) If the cockpit voice recorder has a bulk erasure device, the
installation must be designed to minimize the probability of
inadvertent operation and actuation of the device during crash impact.
    (g) Each recorder container must--
    (1) Be either bright orange or bright yellow;
    (2) Have reflective tape affixed to its external surface to
facilitate its location under water; and
    (3) Have an underwater locating device, when required by the
operating rules of this chapter, on or adjacent to the container, which
is secured in such manner that they are not likely to be separated
during crash impact.

Sec.  23.1459   Flight data recorders.

    (a) Each flight recorder required by the operating rules of this
chapter must be installed so that--
    (1) It is supplied with airspeed, altitude, and directional data
obtained from sources that meet the aircraft level system requirements
and the functionality specified in Sec.  23.2500;
    (2) The vertical acceleration sensor is rigidly attached, and
located longitudinally either within the approved center of gravity
limits of the airplane, or at a distance forward or aft of these limits
that does not exceed 25 percent of the airplane's mean aerodynamic
chord;
    (3)(i) It receives its electrical power from the bus that provides
the maximum reliability for operation of the flight data recorder
without jeopardizing service to essential or emergency loads;
    (ii) It remains powered for as long as possible without
jeopardizing emergency operation of the airplane;
    (4) There is an aural or visual means for preflight checking of the
recorder for proper recording of data in the storage medium;
    (5) Except for recorders powered solely by the engine-driven
electrical generator system, there is an automatic means to
simultaneously stop a recorder that has a data erasure feature and
prevent each erasure feature from functioning, within 10 minutes after
crash impact;
    (6) Any single electrical failure external to the recorder does not
disable both the cockpit voice recorder and the flight data recorder;
and
    (7) It is in a separate container from the cockpit voice recorder
when both are required. If used to comply with only the flight data
recorder requirements, a combination unit may be installed. If a
combination unit is installed as a cockpit voice recorder to comply
with Sec.  23.1457(e)(2), a combination unit must be used to comply
with this flight data recorder requirement.
    (b) Each non-ejectable record container must be located and mounted
so as to minimize the probability of container rupture resulting from
crash impact and subsequent damage to the record from fire. In meeting
this requirement, the record container must be located as far aft as
practicable, but need not be aft of the pressurized compartment, and
may not be where aft-mounted engines may crush the container upon
impact.
    (c) A correlation must be established between the flight recorder
readings of airspeed, altitude, and heading and the corresponding
readings (taking into account correction factors) of the first pilot's
instruments. The correlation must cover the airspeed range over which
the airplane is to be operated, the range of altitude to which the
airplane is limited, and 360 degrees of heading. Correlation may be
established on the ground as appropriate.
    (d) Each recorder container must--
    (1) Be either bright orange or bright yellow;
    (2) Have reflective tape affixed to its external surface to
facilitate its location under water; and
    (3) Have an underwater locating device, when required by the
operating rules of this chapter, on or adjacent to the container, which
is secured in such a manner that they are not likely to be separated
during crash impact.
    (e) Any novel or unique design or operational characteristics of
the aircraft shall be evaluated to determine if any dedicated
parameters must be recorded on flight recorders in addition to or in
place of existing requirements.

Sec.  23.1529   Instructions for continued airworthiness.

    The applicant must prepare Instructions for Continued
Airworthiness, in accordance with appendix A of this part, that are
acceptable to the Administrator. The instructions may be incomplete at
type certification if a program exists to ensure their completion prior
to delivery of the first airplane or issuance of a standard certificate
of airworthiness, whichever occurs later.

Subpart A--General

Sec.  23.2000   Applicability and definitions.

    (a) This part prescribes airworthiness standards for the issuance
of type certificates, and changes to those certificates, for airplanes
in the normal category.
    (b) For the purposes of this part, the following definition
applies:
    Continued safe flight and landing means an airplane is capable of
continued controlled flight and landing, possibly using emergency
procedures, without requiring exceptional pilot skill or strength. Upon
landing, some airplane damage may occur as a result of a failure
condition.

Sec.  23.2005   Certification of normal category airplanes.

    (a) Certification in the normal category applies to airplanes with
a passenger-seating configuration of 19 or less and a maximum
certificated takeoff weight of 19,000 pounds or less.
    (b) Airplane certification levels are:
    (1) Level 1--for airplanes with a maximum seating configuration of
0 to 1 passengers.
    (2) Level 2--for airplanes with a maximum seating configuration of
2 to 6 passengers.
    (3) Level 3--for airplanes with a maximum seating configuration of
7 to 9 passengers.
    (4) Level 4--for airplanes with a maximum seating configuration of
10 to 19 passengers.
    (c) Airplane performance levels are:
    (1) Low speed--for airplanes with a VNO and
VMO <= 250 Knots Calibrated Airspeed (KCAS) and a
MMO <= 0.6.
    (2) High speed--for airplanes with a VNO or
VMO > 250 KCAS or a MMO > 0.6.
    (d) Airplanes not certified for aerobatics may be used to perform
any maneuver incident to normal flying, including--
    (1) Stalls (except whip stalls); and
    (2) Lazy eights, chandelles, and steep turns, in which the angle of
bank is not more than 60 degrees.
    (e) Airplanes certified for aerobatics may be used to perform
maneuvers without limitations, other than those limitations established
under subpart G of this part.

Sec.  23.2010   Accepted means of compliance.

    (a) An applicant must comply with this part using a means of
compliance, which may include consensus standards, accepted by the
Administrator.
    (b) An applicant requesting acceptance of a means of compliance
must provide the means of compliance to the FAA in a form and manner
acceptable to the Administrator.

Subpart B--Flight

Performance

Sec.  23.2100   Weight and center of gravity.

    (a) The applicant must determine limits for weights and centers of
gravity that provide for the safe operation of the airplane.
    (b) The applicant must comply with each requirement of this subpart
at critical combinations of weight and center of gravity within the
airplane's range of loading conditions using tolerances acceptable to
the Administrator.
    (c) The condition of the airplane at the time of determining its
empty weight and center of gravity must be well defined and easily
repeatable.

Sec.  23.2105   Performance data.

    (a) Unless otherwise prescribed, an airplane must meet the
performance requirements of this subpart in--
    (1) Still air and standard atmospheric conditions at sea level for
all airplanes; and
    (2) Ambient atmospheric conditions within the operating envelope
for levels 1 and 2 high-speed and levels 3 and 4 airplanes.
    (b) Unless otherwise prescribed, the applicant must develop the
performance data required by this subpart for the following conditions:
    (1) Airport altitudes from sea level to 10,000 feet (3,048 meters);
and
    (2) Temperatures above and below standard day temperature that are
within the range of operating limitations, if those temperatures could
have a negative effect on performance.
    (c) The procedures used for determining takeoff and landing
distances must be executable consistently by pilots of average skill in
atmospheric conditions expected to be encountered in service.
    (d) Performance data determined in accordance with paragraph (b) of
this section must account for losses due to atmospheric conditions,
cooling needs, and other demands on power sources.

Sec.  23.2110   Stall speed.

    The applicant must determine the airplane stall speed or the
minimum steady flight speed for each flight configuration used in
normal operations, including takeoff, climb, cruise, descent, approach,
and landing. The stall speed or minimum steady flight speed
determination must account for the most adverse conditions for each
flight configuration with power set at--
    (a) Idle or zero thrust for propulsion systems that are used
primarily for thrust; and
    (b) A nominal thrust for propulsion systems that are used for
thrust, flight control, and/or high-lift systems.

Sec.  23.2115   Takeoff performance.

    (a) The applicant must determine airplane takeoff performance
accounting for--
    (1) Stall speed safety margins;
    (2) Minimum control speeds; and
    (3) Climb gradients.
    (b) For single engine airplanes and levels 1, 2, and 3 low-speed
multiengine airplanes, takeoff performance includes the determination
of ground roll and initial climb distance to 50 feet (15 meters) above
the takeoff surface.
    (c) For levels 1, 2, and 3 high-speed multiengine airplanes, and
level 4 multiengine airplanes, takeoff performance includes a
determination the following distances after a sudden critical loss of
thrust--
    (1) An aborted takeoff at critical speed;
    (2) Ground roll and initial climb to 35 feet (11 meters) above the
takeoff surface; and
    (3) Net takeoff flight path.

Sec.  23.2120   Climb requirements.

    The design must comply with the following minimum climb performance
out of ground effect:
    (a) With all engines operating and in the initial climb
configuration--
    (1) For levels 1 and 2 low-speed airplanes, a climb gradient of 8.3
percent for landplanes and 6.7 percent for seaplanes and amphibians;
and
    (2) For levels 1 and 2 high-speed airplanes, all level 3 airplanes,
and level 4 single-engines a climb gradient after takeoff of 4 percent.
    (b) After a critical loss of thrust on multiengine airplanes--
    (1) For levels 1 and 2 low-speed airplanes that do not meet single-
engine crashworthiness requirements, a climb gradient of 1.5 percent at
a pressure altitude of 5,000 feet (1,524 meters) in the cruise
configuration(s);
    (2) For levels 1 and 2 high-speed airplanes, and level 3 low-speed
airplanes, a 1 percent climb gradient at 400 feet (122 meters) above
the takeoff surface with the landing gear retracted and flaps in the
takeoff configuration(s); and
    (3) For level 3 high-speed airplanes and all level 4 airplanes, a 2
percent climb gradient at 400 feet (122 meters) above the takeoff
surface with the landing gear retracted and flaps in the approach
configuration(s).
    (c) For a balked landing, a climb gradient of 3 percent without
creating undue pilot workload with the landing gear extended and flaps
in the landing configuration(s).

Sec.  23.2125   Climb information.

    (a) The applicant must determine climb performance at each weight,
altitude, and ambient temperature within the operating limitations--
    (1) For all single-engine airplanes;
    (2) For levels 1 and 2 high-speed multiengine airplanes and level 3
multiengine airplanes, following a critical loss of thrust on takeoff
in the initial climb configuration; and
    (3) For all multiengine airplanes, during the enroute phase of
flight with all engines operating and after a critical loss of thrust
in the cruise configuration.
    (b) The applicant must determine the glide performance for single-
engine airplanes after a complete loss of thrust.

Sec.  23.2130   Landing.

    The applicant must determine the following, for standard
temperatures at critical combinations of weight and altitude within the
operational limits:
    (a) The distance, starting from a height of 50 feet (15 meters)
above the landing surface, required to land and come to a stop.
    (b) The approach and landing speeds, configurations, and
procedures, which allow a pilot of average skill to land within the
published landing distance consistently and without causing damage or
injury, and which allow for a safe transition to the balked landing
conditions of this part accounting for:
    (1) Stall speed safety margin; and
    (2) Minimum control speeds.

Flight Characteristics

Sec.  23.2135   Controllability.

    (a) The airplane must be controllable and maneuverable, without
requiring exceptional piloting skill, alertness, or strength, within
the operating envelope--
    (1) At all loading conditions for which certification is requested;
    (2) During all phases of flight;
    (3) With likely reversible flight control or propulsion system
failure; and
    (4) During configuration changes.
    (b) The airplane must be able to complete a landing without causing
substantial damage or serious injury using the steepest approved
approach gradient procedures and providing a reasonable margin below
Vref or above approach angle of attack.
    (c) VMC is the calibrated airspeed at which, following
the sudden critical loss of thrust, it is possible to maintain control
of the airplane. For multiengine airplanes, the applicant must
determine VMC, if applicable, for the most critical
configurations used in takeoff and landing operations.

    (d) If the applicant requests certification of an airplane for
aerobatics, the applicant must demonstrate those aerobatic maneuvers
for which certification is requested and determine entry speeds.

Sec.  23.2140   Trim.

    (a) The airplane must maintain lateral and directional trim without
further force upon, or movement of, the primary flight controls or
corresponding trim controls by the pilot, or the flight control system,
under the following conditions:
    (1) For levels 1, 2, and 3 airplanes in cruise.
    (2) For level 4 airplanes in normal operations.
    (b) The airplane must maintain longitudinal trim without further
force upon, or movement of, the primary flight controls or
corresponding trim controls by the pilot, or the flight control system,
under the following conditions:
    (1) Climb.
    (2) Level flight.
    (3) Descent.
    (4) Approach.
    (c) Residual control forces must not fatigue or distract the pilot
during normal operations of the airplane and likely abnormal or
emergency operations, including a critical loss of thrust on
multiengine airplanes.

Sec.  23.2145   Stability.

    (a) Airplanes not certified for aerobatics must--
    (1) Have static longitudinal, lateral, and directional stability in
normal operations;
    (2) Have dynamic short period and Dutch roll stability in normal
operations; and
    (3) Provide stable control force feedback throughout the operating
envelope.
    (b) No airplane may exhibit any divergent longitudinal stability
characteristic so unstable as to increase the pilot's workload or
otherwise endanger the airplane and its occupants.

Sec.  23.2150   Stall characteristics, stall warning, and spins.

    (a) The airplane must have controllable stall characteristics in
straight flight, turning flight, and accelerated turning flight with a
clear and distinctive stall warning that provides sufficient margin to
prevent inadvertent stalling.
    (b) Single-engine airplanes, not certified for aerobatics, must not
have a tendency to inadvertently depart controlled flight.
    (c) Levels 1 and 2 multiengine airplanes, not certified for
aerobatics, must not have a tendency to inadvertently depart controlled
flight from thrust asymmetry after a critical loss of thrust.
    (d) Airplanes certified for aerobatics that include spins must have
controllable stall characteristics and the ability to recover within
one and one-half additional turns after initiation of the first control
action from any point in a spin, not exceeding six turns or any greater
number of turns for which certification is requested, while remaining
within the operating limitations of the airplane.
    (e) Spin characteristics in airplanes certified for aerobatics that
includes spins must recover without exceeding limitations and may not
result in unrecoverable spins--
    (1) With any typical use of the flight or engine power controls; or
    (2) Due to pilot disorientation or incapacitation.

Sec.  23.2155   Ground and water handling characteristics.

    For airplanes intended for operation on land or water, the airplane
must have controllable longitudinal and directional handling
characteristics during taxi, takeoff, and landing operations.

Sec.  23.2160   Vibration, buffeting, and high-speed characteristics.

    (a) Vibration and buffeting, for operations up to VD/
MD, must not interfere with the control of the airplane or
cause excessive fatigue to the flightcrew. Stall warning buffet within
these limits is allowable.
    (b) For high-speed airplanes and all airplanes with a maximum
operating altitude greater than 25,000 feet (7,620 meters) pressure
altitude, there must be no perceptible buffeting in cruise
configuration at 1g and at any speed up to VMO/
MMO, except stall buffeting.
    (c) For high-speed airplanes, the applicant must determine the
positive maneuvering load factors at which the onset of perceptible
buffet occurs in the cruise configuration within the operational
envelope. Likely inadvertent excursions beyond this boundary must not
result in structural damage.
    (d) High-speed airplanes must have recovery characteristics that do
not result in structural damage or loss of control, beginning at any
likely speed up to VMO/MMO, following--
    (1) An inadvertent speed increase; and
    (2) A high-speed trim upset for airplanes where dynamic pressure
can impair the longitudinal trim system operation.

Sec.  23.2165   Performance and flight characteristics requirements for
flight in icing conditions.

    (a) An applicant who requests certification for flight in icing
conditions defined in part 1 of appendix C to part 25 of this chapter,
or an applicant who requests certification for flight in these icing
conditions and any additional atmospheric icing conditions, must show
the following in the icing conditions for which certification is
requested under normal operation of the ice protection system(s):
    (1) Compliance with each requirement of this subpart, except those
applicable to spins and any that must be demonstrated at speeds in
excess of--
    (i) 250 knots CAS;
    (ii) VMO/MMO or VNE; or
    (iii) A speed at which the applicant demonstrates the airframe will
be free of ice accretion.
    (2) The means by which stall warning is provided to the pilot for
flight in icing conditions and non-icing conditions is the same.
    (b) If an applicant requests certification for flight in icing
conditions, the applicant must provide a means to detect any icing
conditions for which certification is not requested and show the
airplane's ability to avoid or exit those conditions.
    (c) The applicant must develop an operating limitation to prohibit
intentional flight, including takeoff and landing, into icing
conditions for which the airplane is not certified to operate.

Subpart C--Structures

Sec.  23.2200   Structural design envelope.

    The applicant must determine the structural design envelope, which
describes the range and limits of airplane design and operational
parameters for which the applicant will show compliance with the
requirements of this subpart. The applicant must account for all
airplane design and operational parameters that affect structural
loads, strength, durability, and aeroelasticity, including:
    (a) Structural design airspeeds, landing descent speeds, and any
other airspeed limitation at which the applicant must show compliance
to the requirements of this subpart. The structural design airspeeds
must--
    (1) Be sufficiently greater than the stalling speed of the airplane
to safeguard against loss of control in turbulent air; and
    (2) Provide sufficient margin for the establishment of practical
operational limiting airspeeds.
    (b) Design maneuvering load factors not less than those, which
service

history shows, may occur within the structural design envelope.
    (c) Inertial properties including weight, center of gravity, and
mass moments of inertia, accounting for--
    (1) Each critical weight from the airplane empty weight to the
maximum weight; and
    (2) The weight and distribution of occupants, payload, and fuel.
    (d) Characteristics of airplane control systems, including range of
motion and tolerances for control surfaces, high lift devices, or other
moveable surfaces.
    (e) Each critical altitude up to the maximum altitude.

Sec.  23.2205   Interaction of systems and structures.

    For airplanes equipped with systems that modify structural
performance, alleviate the impact of this subpart's requirements, or
provide a means of compliance with this subpart, the applicant must
account for the influence and failure of these systems when showing
compliance with the requirements of this subpart.

Structural Loads

Sec.  23.2210   Structural design loads.

    (a) The applicant must:
    (1) Determine the applicable structural design loads resulting from
likely externally or internally applied pressures, forces, or moments
that may occur in flight, ground and water operations, ground and water
handling, and while the airplane is parked or moored.
    (2) Determine the loads required by paragraph (a)(1) of this
section at all critical combinations of parameters, on and within the
boundaries of the structural design envelope.
    (b) The magnitude and distribution of the applicable structural
design loads required by this section must be based on physical
principles.

Sec.  23.2215   Flight load conditions.

    The applicant must determine the structural design loads resulting
from the following flight conditions:
    (a) Atmospheric gusts where the magnitude and gradient of these
gusts are based on measured gust statistics.
    (b) Symmetric and asymmetric maneuvers.
    (c) Asymmetric thrust resulting from the failure of a powerplant
unit.

Sec.  23.2220   Ground and water load conditions.

    The applicant must determine the structural design loads resulting
from taxi, takeoff, landing, and handling conditions on the applicable
surface in normal and adverse attitudes and configurations.

Sec.  23.2225   Component loading conditions.

    The applicant must determine the structural design loads acting on:
    (a) Each engine mount and its supporting structure such that both
are designed to withstand loads resulting from--
    (1) Powerplant operation combined with flight gust and maneuver
loads; and
    (2) For non-reciprocating powerplants, sudden powerplant stoppage.
    (b) Each flight control and high-lift surface, their associated
system and supporting structure resulting from--
    (1) The inertia of each surface and mass balance attachment;
    (2) Flight gusts and maneuvers;
    (3) Pilot or automated system inputs;
    (4) System induced conditions, including jamming and friction; and
    (5) Taxi, takeoff, and landing operations on the applicable
surface, including downwind taxi and gusts occurring on the applicable
surface.
    (c) A pressurized cabin resulting from the pressurization
differential--
    (1) From zero up to the maximum relief pressure combined with gust
and maneuver loads;
    (2) From zero up to the maximum relief pressure combined with
ground and water loads if the airplane may land with the cabin
pressurized; and
    (3) At the maximum relief pressure multiplied by 1.33, omitting all
other loads.

Sec.  23.2230   Limit and ultimate loads.

    The applicant must determine--
    (a) The limit loads, which are equal to the structural design loads
unless otherwise specified elsewhere in this part; and
    (b) The ultimate loads, which are equal to the limit loads
multiplied by a 1.5 factor of safety unless otherwise specified
elsewhere in this part.

Structural Performance

Sec.  23.2235   Structural strength.

    The structure must support:
    (a) Limit loads without--
    (1) Interference with the safe operation of the airplane; and
    (2) Detrimental permanent deformation.
    (b) Ultimate loads.

Sec.  23.2240   Structural durability.

    (a) The applicant must develop and implement inspections or other
procedures to prevent structural failures due to foreseeable causes of
strength degradation, which could result in serious or fatal injuries,
or extended periods of operation with reduced safety margins. Each of
the inspections or other procedures developed under this section must
be included in the Airworthiness Limitations Section of the
Instructions for Continued Airworthiness required by Sec.  23.1529.
    (b) For Level 4 airplanes, the procedures developed for compliance
with paragraph (a) of this section must be capable of detecting
structural damage before the damage could result in structural failure.
    (c) For pressurized airplanes:
    (1) The airplane must be capable of continued safe flight and
landing following a sudden release of cabin pressure, including sudden
releases caused by door and window failures.
    (2) For airplanes with maximum operating altitude greater than
41,000 feet, the procedures developed for compliance with paragraph (a)
of this section must be capable of detecting damage to the pressurized
cabin structure before the damage could result in rapid decompression
that would result in serious or fatal injuries.
    (d) The airplane must be designed to minimize hazards to the
airplane due to structural damage caused by high-energy fragments from
an uncontained engine or rotating machinery failure.

Sec.  23.2245   Aeroelasticity.

    (a) The airplane must be free from flutter, control reversal, and
divergence--
    (1) At all speeds within and sufficiently beyond the structural
design envelope;
    (2) For any configuration and condition of operation;
    (3) Accounting for critical degrees of freedom; and
    (4) Accounting for any critical failures or malfunctions.
    (b) The applicant must establish tolerances for all quantities that
affect flutter.

Design

Sec.  23.2250   Design and construction principles.

    (a) The applicant must design each part, article, and assembly for
the expected operating conditions of the airplane.
    (b) Design data must adequately define the part, article, or
assembly configuration, its design features, and any materials and
processes used.
    (c) The applicant must determine the suitability of each design
detail and part having an important bearing on safety in operations.
    (d) The control system must be free from jamming, excessive
friction, and excessive deflection when the airplane is subjected to
expected limit airloads.
    (e) Doors, canopies, and exits must be protected against
inadvertent opening in

flight, unless shown to create no hazard when opened in flight.

Sec.  23.2255   Protection of structure.

    (a) The applicant must protect each part of the airplane, including
small parts such as fasteners, against deterioration or loss of
strength due to any cause likely to occur in the expected operational
environment.
    (b) Each part of the airplane must have adequate provisions for
ventilation and drainage.
    (c) For each part that requires maintenance, preventive
maintenance, or servicing, the applicant must incorporate a means into
the aircraft design to allow such actions to be accomplished.

Sec.  23.2260  Materials and processes.

    (a) The applicant must determine the suitability and durability of
materials used for parts, articles, and assemblies, accounting for the
effects of likely environmental conditions expected in service, the
failure of which could prevent continued safe flight and landing.
    (b) The methods and processes of fabrication and assembly used must
produce consistently sound structures. If a fabrication process
requires close control to reach this objective, the applicant must
perform the process under an approved process specification.
    (c) Except as provided in paragraphs (f) and (g) of this section,
the applicant must select design values that ensure material strength
with probabilities that account for the criticality of the structural
element. Design values must account for the probability of structural
failure due to material variability.
    (d) If material strength properties are required, a determination
of those properties must be based on sufficient tests of material
meeting specifications to establish design values on a statistical
basis.
    (e) If thermal effects are significant on a critical component or
structure under normal operating conditions, the applicant must
determine those effects on allowable stresses used for design.
    (f) Design values, greater than the minimums specified by this
section, may be used, where only guaranteed minimum values are normally
allowed, if a specimen of each individual item is tested before use to
determine that the actual strength properties of that particular item
will equal or exceed those used in the design.
    (g) An applicant may use other material design values if approved
by the Administrator.

Sec.  23.2265  Special factors of safety.

    (a) The applicant must determine a special factor of safety for
each critical design value for each part, article, or assembly for
which that critical design value is uncertain, and for each part,
article, or assembly that is--
    (1) Likely to deteriorate in service before normal replacement; or
    (2) Subject to appreciable variability because of uncertainties in
manufacturing processes or inspection methods.
    (b) The applicant must determine a special factor of safety using
quality controls and specifications that account for each--
    (1) Type of application;
    (2) Inspection method;
    (3) Structural test requirement;
    (4) Sampling percentage; and
    (5) Process and material control.
    (c) The applicant must multiply the highest pertinent special
factor of safety in the design for each part of the structure by each
limit and ultimate load, or ultimate load only, if there is no
corresponding limit load, such as occurs with emergency condition
loading.

Structural Occupant Protection

Sec.  23.2270  Emergency conditions.

    (a) The airplane, even when damaged in an emergency landing, must
protect each occupant against injury that would preclude egress when--
    (1) Properly using safety equipment and features provided for in
the design;
    (2) The occupant experiences ultimate static inertia loads likely
to occur in an emergency landing; and
    (3) Items of mass, including engines or auxiliary power units
(APUs), within or aft of the cabin, that could injure an occupant,
experience ultimate static inertia loads likely to occur in an
emergency landing.
    (b) The emergency landing conditions specified in paragraph (a)(1)
and (a)(2) of this section, must--
    (1) Include dynamic conditions that are likely to occur in an
emergency landing; and
    (2) Not generate loads experienced by the occupants, which exceed
established human injury criteria for human tolerance due to restraint
or contact with objects in the airplane.
    (c) The airplane must provide protection for all occupants,
accounting for likely flight, ground, and emergency landing conditions.
    (d) Each occupant protection system must perform its intended
function and not create a hazard that could cause a secondary injury to
an occupant. The occupant protection system must not prevent occupant
egress or interfere with the operation of the airplane when not in use.
    (e) Each baggage and cargo compartment must--
    (1) Be designed for its maximum weight of contents and for the
critical load distributions at the maximum load factors corresponding
to the flight and ground load conditions determined under this part;
    (2) Have a means to prevent the contents of the compartment from
becoming a hazard by impacting occupants or shifting; and
    (3) Protect any controls, wiring, lines, equipment, or accessories
whose damage or failure would affect safe operations.

Subpart D--Design and Construction

Sec.  23.2300   Flight control systems.

    (a) The applicant must design airplane flight control systems to:
    (1) Operate easily, smoothly, and positively enough to allow proper
performance of their functions.
    (2) Protect against likely hazards.
    (b) The applicant must design trim systems, if installed, to:
    (1) Protect against inadvertent, incorrect, or abrupt trim
operation.
    (2) Provide a means to indicate--
    (i) The direction of trim control movement relative to airplane
motion;
    (ii) The trim position with respect to the trim range;
    (iii) The neutral position for lateral and directional trim; and
    (iv) The range for takeoff for all applicant requested center of
gravity ranges and configurations.

Sec.  23.2305   Landing gear systems.

    (a) The landing gear must be designed to--
    (1) Provide stable support and control to the airplane during
surface operation; and
    (2) Account for likely system failures and likely operation
environments (including anticipated limitation exceedances and
emergency procedures).
    (b) All airplanes must have a reliable means of stopping the
airplane with sufficient kinetic energy absorption to account for
landing. Airplanes that are required to demonstrate aborted takeoff
capability must account for this additional kinetic energy.
    (c) For airplanes that have a system that actuates the landing
gear, there is--
    (1) A positive means to keep the landing gear in the landing
position; and
    (2) An alternative means available to bring the landing gear in the
landing position when a non-deployed system position would be a hazard.

Sec.  23.2310   Buoyancy for seaplanes and amphibians.

    Airplanes intended for operations on water, must--
    (a) Provide buoyancy of 80 percent in excess of the buoyancy
required to support the maximum weight of the airplane in fresh water;
and
    (b) Have sufficient margin so the airplane will stay afloat at rest
in calm water without capsizing in case of a likely float or hull
flooding.

Occupant System Design Protection

Sec.  23.2315   Means of egress and emergency exits.

    (a) With the cabin configured for takeoff or landing, the airplane
is designed to:
    (1) Facilitate rapid and safe evacuation of the airplane in
conditions likely to occur following an emergency landing, excluding
ditching for level 1, level 2 and single engine level 3 airplanes.
    (2) Have means of egress (openings, exits or emergency exits), that
can be readily located and opened from the inside and outside. The
means of opening must be simple and obvious and marked inside and
outside the airplane.
    (3) Have easy access to emergency exits when present.
    (b) Airplanes approved for aerobatics must have a means to egress
the airplane in flight.

Sec.  23.2320  Occupant physical environment.

    (a) The applicant must design the airplane to--
    (1) Allow clear communication between the flightcrew and
passengers;
    (2) Protect the pilot and flight controls from propellers; and
    (3) Protect the occupants from serious injury due to damage to
windshields, windows, and canopies.
    (b) For level 4 airplanes, each windshield and its supporting
structure directly in front of the pilot must withstand, without
penetration, the impact equivalent to a two-pound bird when the
velocity of the airplane is equal to the airplane's maximum approach
flap speed.
    (c) The airplane must provide each occupant with air at a
breathable pressure, free of hazardous concentrations of gases, vapors,
and smoke during normal operations and likely failures.
    (d) If a pressurization system is installed in the airplane, it
must be designed to protect against--
    (1) Decompression to an unsafe level; and
    (2) Excessive differential pressure.
    (e) If an oxygen system is installed in the airplane, it must--
    (1) Effectively provide oxygen to each user to prevent the effects
of hypoxia; and
    (2) Be free from hazards in itself, in its method of operation, and
its effect upon other components.

Fire and High Energy Protection

Sec.  23.2325  Fire protection.

    (a) The following materials must be self-extinguishing--
    (1) Insulation on electrical wire and electrical cable;
    (2) For levels 1, 2, and 3 airplanes, materials in the baggage and
cargo compartments inaccessible in flight; and
    (3) For level 4 airplanes, materials in the cockpit, cabin,
baggage, and cargo compartments.
    (b) The following materials must be flame resistant--
    (1) For levels 1, 2 and 3 airplanes, materials in each compartment
accessible in flight; and
    (2) Any equipment associated with any electrical cable installation
and that would overheat in the event of circuit overload or fault.
    (c) Thermal/acoustic materials in the fuselage, if installed, must
not be a flame propagation hazard.
    (d) Sources of heat within each baggage and cargo compartment that
are capable of igniting adjacent objects must be shielded and insulated
to prevent such ignition.
    (e) For level 4 airplanes, each baggage and cargo compartment
must--
    (1) Be located where a fire would be visible to the pilots, or
equipped with a fire detection system and warning system; and
    (2) Be accessible for the manual extinguishing of a fire, have a
built-in fire extinguishing system, or be constructed and sealed to
contain any fire within the compartment.
    (f) There must be a means to extinguish any fire in the cabin such
that--
    (1) The pilot, while seated, can easily access the fire
extinguishing means; and
    (2) For levels 3 and 4 airplanes, passengers have a fire
extinguishing means available within the passenger compartment.
    (g) Each area where flammable fluids or vapors might escape by
leakage of a fluid system must--
    (1) Be defined; and
    (2) Have a means to minimize the probability of fluid and vapor
ignition, and the resultant hazard, if ignition occurs.
    (h) Combustion heater installations must be protected from
uncontained fire.

Sec.  23.2330  Fire protection in designated fire zones and adjacent
areas.

    (a) Flight controls, engine mounts, and other flight structures
within or adjacent to designated fire zones must be capable of
withstanding the effects of a fire.
    (b) Engines in a designated fire zone must remain attached to the
airplane in the event of a fire.
    (c) In designated fire zones, terminals, equipment, and electrical
cables used during emergency procedures must be fire-resistant.

Sec.  23.2335  Lightning protection.

    The airplane must be protected against catastrophic effects from
lightning.

Subpart E--Powerplant

Sec.  23.2400  Powerplant installation.

    (a) For the purpose of this subpart, the airplane powerplant
installation must include each component necessary for propulsion,
which affects propulsion safety, or provides auxiliary power to the
airplane.
    (b) Each airplane engine and propeller must be type certificated,
except for engines and propellers installed on level 1 low-speed
airplanes, which may be approved under the airplane type certificate in
accordance with a standard accepted by the FAA that contains
airworthiness criteria the Administrator has found appropriate and
applicable to the specific design and intended use of the engine or
propeller and provides a level of safety acceptable to the FAA.
    (c) The applicant must construct and arrange each powerplant
installation to account for--
    (1) Likely operating conditions, including foreign object threats;
    (2) Sufficient clearance of moving parts to other airplane parts
and their surroundings;
    (3) Likely hazards in operation including hazards to ground
personnel; and
    (4) Vibration and fatigue.
    (d) Hazardous accumulations of fluids, vapors, or gases must be
isolated from the airplane and personnel compartments, and be safely
contained or discharged.
    (e) Powerplant components must comply with their component
limitations and installation instructions or be shown not to create a
hazard.

Sec.  23.2405  Automatic power or thrust control systems.

    (a) An automatic power or thrust control system intended for in-
flight use must be designed so no unsafe condition will result during
normal operation of the system.

    (b) Any single failure or likely combination of failures of an
automatic power or thrust control system must not prevent continued
safe flight and landing of the airplane.
    (c) Inadvertent operation of an automatic power or thrust control
system by the flightcrew must be prevented, or if not prevented, must
not result in an unsafe condition.
    (d) Unless the failure of an automatic power or thrust control
system is extremely remote, the system must--
    (1) Provide a means for the flightcrew to verify the system is in
an operating condition;
    (2) Provide a means for the flightcrew to override the automatic
function; and
    (3) Prevent inadvertent deactivation of the system.

Sec.  23.2410  Powerplant installation hazard assessment.

    The applicant must assess each powerplant separately and in
relation to other airplane systems and installations to show that any
hazard resulting from the likely failure of any powerplant system,
component, or accessory will not--
    (a) Prevent continued safe flight and landing or, if continued safe
flight and landing cannot be ensured, the hazard has been minimized;
    (b) Cause serious injury that may be avoided; and
    (c) Require immediate action by any crewmember for continued
operation of any remaining powerplant system.

Sec.  23.2415  Powerplant ice protection.

    (a) The airplane design, including the induction and inlet system,
must prevent foreseeable accumulation of ice or snow that adversely
affects powerplant operation.
    (b) The powerplant installation design must prevent any
accumulation of ice or snow that adversely affects powerplant
operation, in those icing conditions for which certification is
requested.

Sec.  23.2420  Reversing systems.

    Each reversing system must be designed so that--
    (a) No unsafe condition will result during normal operation of the
system; and
    (b) The airplane is capable of continued safe flight and landing
after any single failure, likely combination of failures, or
malfunction of the reversing system.

Sec.  23.2425   Powerplant operational characteristics.

    (a) The installed powerplant must operate without any hazardous
characteristics during normal and emergency operation within the range
of operating limitations for the airplane and the engine.
    (b) The pilot must have the capability to stop the powerplant in
flight and restart the powerplant within an established operational
envelope.

Sec.  23.2430   Fuel systems.

    (a) Each fuel system must--
    (1) Be designed and arranged to provide independence between
multiple fuel storage and supply systems so that failure of any one
component in one system will not result in loss of fuel storage or
supply of another system;
    (2) Be designed and arranged to prevent ignition of the fuel within
the system by direct lightning strikes or swept lightning strokes to
areas where such occurrences are highly probable, or by corona or
streamering at fuel vent outlets;
    (3) Provide the fuel necessary to ensure each powerplant and
auxiliary power unit functions properly in all likely operating
conditions;
    (4) Provide the flightcrew with a means to determine the total
useable fuel available and provide uninterrupted supply of that fuel
when the system is correctly operated, accounting for likely fuel
fluctuations;
    (5) Provide a means to safely remove or isolate the fuel stored in
the system from the airplane;
    (6) Be designed to retain fuel under all likely operating
conditions and minimize hazards to the occupants during any survivable
emergency landing. For level 4 airplanes, failure due to overload of
the landing system must be taken into account; and
    (7) Prevent hazardous contamination of the fuel supplied to each
powerplant and auxiliary power unit.
    (b) Each fuel storage system must--
    (1) Withstand the loads under likely operating conditions without
failure;
    (2) Be isolated from personnel compartments and protected from
hazards due to unintended temperature influences;
    (3) Be designed to prevent significant loss of stored fuel from any
vent system due to fuel transfer between fuel storage or supply
systems, or under likely operating conditions;
    (4) Provide fuel for at least one-half hour of operation at maximum
continuous power or thrust; and
    (5) Be capable of jettisoning fuel safely if required for landing.
    (c) Each fuel storage refilling or recharging system must be
designed to--
    (1) Prevent improper refilling or recharging;
    (2) Prevent contamination of the fuel stored during likely
operating conditions; and
    (3) Prevent the occurrence of any hazard to the airplane or to
persons during refilling or recharging.

Sec.  23.2435   Powerplant induction and exhaust systems.

    (a) The air induction system for each powerplant or auxiliary power
unit and their accessories must--
    (1) Supply the air required by that powerplant or auxiliary power
unit and its accessories under likely operating conditions;
    (2) Be designed to prevent likely hazards in the event of fire or
backfire;
    (3) Minimize the ingestion of foreign matter; and
    (4) Provide an alternate intake if blockage of the primary intake
is likely.
    (b) The exhaust system, including exhaust heat exchangers for each
powerplant or auxiliary power unit, must--
    (1) Provide a means to safely discharge potential harmful material;
and
    (2) Be designed to prevent likely hazards from heat, corrosion, or
blockage.

Sec.  23.2440   Powerplant fire protection.

    (a) A powerplant, auxiliary power unit, or combustion heater that
includes a flammable fluid and an ignition source for that fluid must
be installed in a designated fire zone.
    (b) Each designated fire zone must provide a means to isolate and
mitigate hazards to the airplane in the event of fire or overheat
within the zone.
    (c) Each component, line, fitting, and control subject to fire
conditions must--
    (1) Be designed and located to prevent hazards resulting from a
fire, including any located adjacent to a designated fire zone that may
be affected by fire within that zone;
    (2) Be fire resistant if carrying flammable fluids, gas, or air or
required to operate in event of a fire; and
    (3) Be fireproof or enclosed by a fire proof shield if storing
concentrated flammable fluids.
    (d) The applicant must provide a means to prevent hazardous
quantities of flammable fluids from flowing into, within or through
each designated fire zone. This means must--
    (1) Not restrict flow or limit operation of any remaining
powerplant or auxiliary power unit, or equipment necessary for safety;
    (2) Prevent inadvertent operation; and
    (3) Be located outside the fire zone unless an equal degree of
safety is provided with a means inside the fire zone.
    (e) A means to ensure the prompt detection of fire must be provided
for each designated fire zone--

    (1) On a multiengine airplane where detection will mitigate likely
hazards to the airplane; or
    (2) That contains a fire extinguisher.
    (f) A means to extinguish fire within a fire zone, except a
combustion heater fire zone, must be provided for--
    (1) Any fire zone located outside the pilot's view;
    (2) Any fire zone embedded within the fuselage, which must also
include a redundant means to extinguish fire; and
    (3) Any fire zone on a level 4 airplane.

Subpart F--Equipment

Sec.  23.2500   Airplane level systems requirements.

    This section applies generally to installed equipment and systems
unless a section of this part imposes requirements for a specific piece
of equipment, system, or systems.
    (a) The equipment and systems required for an airplane to operate
safely in the kinds of operations for which certification is requested
(Day VFR, Night VFR, IFR) must be designed and installed to--
    (1) Meet the level of safety applicable to the certification and
performance level of the airplane; and
    (2) Perform their intended function throughout the operating and
environmental limits for which the airplane is certificated.
    (b) The systems and equipment not covered by paragraph (a),
considered separately and in relation to other systems, must be
designed and installed so their operation does not have an adverse
effect on the airplane or its occupants.

Sec.  23.2505   Function and installation.

    When installed, each item of equipment must function as intended.

Sec.  23.2510   Equipment, systems, and installations.

    For any airplane system or equipment whose failure or abnormal
operation has not been specifically addressed by another requirement in
this part, the applicant must design and install each system and
equipment, such that there is a logical and acceptable inverse
relationship between the average probability and the severity of
failure conditions to the extent that:
    (a) Each catastrophic failure condition is extremely improbable;
    (b) Each hazardous failure condition is extremely remote; and
    (c) Each major failure condition is remote.

Sec.  23.2515   Electrical and electronic system lightning protection.

    An airplane approved for IFR operations must meet the following
requirements, unless an applicant shows that exposure to lightning is
unlikely:
    (a) Each electrical or electronic system that performs a function,
the failure of which would prevent the continued safe flight and
landing of the airplane, must be designed and installed such that--
    (1) The function at the airplane level is not adversely affected
during and after the time the airplane is exposed to lightning; and
    (2) The system recovers normal operation of that function in a
timely manner after the airplane is exposed to lightning unless the
system's recovery conflicts with other operational or functional
requirements of the system.
    (b) Each electrical and electronic system that performs a function,
the failure of which would significantly reduce the capability of the
airplane or the ability of the flightcrew to respond to an adverse
operating condition, must be designed and installed such that the
system recovers normal operation of that function in a timely manner
after the airplane is exposed to lightning.

Sec.  23.2520   High-intensity Radiated Fields (HIRF) protection.

    (a) Each electrical and electronic systems that perform a function,
the failure of which would prevent the continued safe flight and
landing of the airplane, must be designed and installed such that--
    (1) The function at the airplane level is not adversely affected
during and after the time the airplane is exposed to the HIRF
environment; and
    (2) The system recovers normal operation of that function in a
timely manner after the airplane is exposed to the HIRF environment,
unless the system's recovery conflicts with other operational or
functional requirements of the system.
    (b) For airplanes approved for IFR operations, each electrical and
electronic system that performs a function, the failure of which would
significantly reduce the capability of the airplane or the ability of
the flightcrew to respond to an adverse operating condition, must be
designed and installed such that the system recovers normal operation
of that function in a timely manner after the airplane is exposed to
the HIRF environment.

Sec.  23.2525   System power generation, storage, and distribution.

    The power generation, storage, and distribution for any system must
be designed and installed to--
    (a) Supply the power required for operation of connected loads
during all intended operating conditions;
    (b) Ensure no single failure or malfunction of any one power
supply, distribution system, or other utilization system will prevent
the system from supplying the essential loads required for continued
safe flight and landing; and
    (c) Have enough capacity, if the primary source fails, to supply
essential loads, including non-continuous essential loads for the time
needed to complete the function required for continued safe flight and
landing.

Sec.  23.2530   External and cockpit lighting.

    (a) The applicant must design and install all lights to minimize
any adverse effects on the performance of flightcrew duties.
    (b) Any position and anti-collision lights, if required by part 91
of this chapter, must have the intensities, flash rate, colors, fields
of coverage, and other characteristics to provide sufficient time for
another aircraft to avoid a collision.
    (c) Any position lights, if required by part 91 of this chapter,
must include a red light on the left side of the airplane, a green
light on the right side of the airplane, spaced laterally as far apart
as practicable, and a white light facing aft, located on an aft portion
of the airplane or on the wing tips.
    (d) Any taxi and landing lights must be designed and installed so
they provide sufficient light for night operations.
    (e) For seaplanes or amphibian airplanes, riding lights must
provide a white light visible in clear atmospheric conditions.

Sec.  23.2535   Safety equipment.

    Safety and survival equipment, required by the operating rules of
this chapter, must be reliable, readily accessible, easily
identifiable, and clearly marked to identify its method of operation.

Sec.  23.2540   Flight in icing conditions.

    An applicant who requests certification for flight in icing
conditions defined in part 1 of appendix C to part 25 of this chapter,
or an applicant who requests certification for flight in these icing
conditions and any additional atmospheric icing conditions, must show
the following in the icing conditions for which certification is
requested:
    (a) The ice protection system provides for safe operation.
    (b) The airplane design must provide protection from stalling when
the autopilot is operating.

Sec.  23.2545   Pressurized systems elements.

    Pressurized systems must withstand appropriate proof and burst
pressures.

Sec.  23.2550   Equipment containing high-energy rotors.

    Equipment containing high-energy rotors must be designed or
installed to protect the occupants and airplane from uncontained
fragments.

Subpart G--Flightcrew Interface and Other Information

Sec.  23.2600   Flightcrew interface.

    (a) The pilot compartment, its equipment, and its arrangement to
include pilot view, must allow each pilot to perform his or her duties,
including taxi, takeoff, climb, cruise, descent, approach, landing, and
perform any maneuvers within the operating envelope of the airplane,
without excessive concentration, skill, alertness, or fatigue.
    (b) The applicant must install flight, navigation, surveillance,
and powerplant controls and displays so qualified flightcrew can
monitor and perform defined tasks associated with the intended
functions of systems and equipment. The system and equipment design
must minimize flightcrew errors, which could result in additional
hazards.
    (c) For level 4 airplanes, the flightcrew interface design must
allow for continued safe flight and landing after the loss of vision
through any one of the windshield panels.

Sec.  23.2605   Installation and operation.

    (a) Each item of installed equipment related to the flightcrew
interface must be labelled, if applicable, as to it identification,
function, or operating limitations, or any combination of these
factors.
    (b) There must be a discernible means of providing system operating
parameters required to operate the airplane, including warnings,
cautions, and normal indications to the responsible crewmember.
    (c) Information concerning an unsafe system operating condition
must be provided in a timely manner to the crewmember responsible for
taking corrective action. The information must be clear enough to avoid
likely crewmember errors.

Sec.  23.2610   Instrument markings, control markings, and placards.

    (a) Each airplane must display in a conspicuous manner any placard
and instrument marking necessary for operation.
    (b) The design must clearly indicate the function of each cockpit
control, other than primary flight controls.
    (c) The applicant must include instrument marking and placard
information in the Airplane Flight Manual.

Sec.  23.2615   Flight, navigation, and powerplant instruments.

    (a) Installed systems must provide the flightcrew member who sets
or monitors parameters for the flight, navigation, and powerplant, the
information necessary to do so during each phase of flight. This
information must--
    (1) Be presented in a manner that the crewmember can monitor the
parameter and determine trends, as needed, to operate the airplane; and
    (2) Include limitations, unless the limitation cannot be exceeded
in all intended operations.
    (b) Indication systems that integrate the display of flight or
powerplant parameters to operate the airplane or are required by the
operating rules of this chapter must--
    (1) Not inhibit the primary display of flight or powerplant
parameters needed by any flightcrew member in any normal mode of
operation; and
    (2) In combination with other systems, be designed and installed so
information essential for continued safe flight and landing will be
available to the flightcrew in a timely manner after any single failure
or probable combination of failures.

Sec.  23.2620   Airplane flight manual.

    The applicant must provide an Airplane Flight Manual that must be
delivered with each airplane.
    (a) The Airplane Flight Manual must contain the following
information--
    (1) Airplane operating limitations;
    (2) Airplane operating procedures;
    (3) Performance information;
    (4) Loading information; and
    (5) Other information that is necessary for safe operation because
of design, operating, or handling characteristics.
    (b) The following sections of the Airplane Flight Manual must be
approved by the FAA in a manner specified by the administrator--
    (1) For low-speed, level 1 and 2 airplanes, those portions of the
Airplane Flight Manual containing the information specified in
paragraph (a)(1) of this section; and
    (2) For high-speed level 1 and 2 airplanes and all level 3 and 4
airplanes, those portions of the Airplane Flight Manual containing the
information specified in paragraphs (a)(1) thru (a)(4) of this section.

Appendix A to Part 23--Instructions for Continued Airworthiness

A23.1 General

    (a) This appendix specifies requirements for the preparation of
Instructions for Continued Airworthiness as required by this part.
    (b) The Instructions for Continued Airworthiness for each
airplane must include the Instructions for Continued Airworthiness
for each engine and propeller (hereinafter designated ``products''),
for each appliance required by this chapter, and any required
information relating to the interface of those appliances and
products with the airplane. If Instructions for Continued
Airworthiness are not supplied by the manufacturer of an appliance
or product installed in the airplane, the Instructions for Continued
Airworthiness for the airplane must include the information
essential to the continued airworthiness of the airplane.
    (c) The applicant must submit to the FAA a program to show how
changes to the Instructions for Continued Airworthiness made by the
applicant or by the manufacturers of products and appliances
installed in the airplane will be distributed.

A23.2 Format

    (a) The Instructions for Continued Airworthiness must be in the
form of a manual or manuals as appropriate for the quantity of data
to be provided.
    (b) The format of the manual or manuals must provide for a
practical arrangement.

A23.3 Content

    The contents of the manual or manuals must be prepared in the
English language. The Instructions for Continued Airworthiness must
contain the following manuals or sections and information:
    (a) Airplane maintenance manual or section.
    (1) Introduction information that includes an explanation of the
airplane's features and data to the extent necessary for maintenance
or preventive maintenance.
    (2) A description of the airplane and its systems and
installations including its engines, propellers, and appliances.
    (3) Basic control and operation information describing how the
airplane components and systems are controlled and how they operate,
including any special procedures and limitations that apply.
    (4) Servicing information that covers details regarding
servicing points, capacities of tanks, reservoirs, types of fluids
to be used, pressures applicable to the various systems, location of
access panels for inspection and servicing, locations of lubrication
points, lubricants to be used, equipment required for servicing, tow
instructions and limitations, mooring, jacking, and leveling
information.
    (b) Maintenance Instructions.
    (1) Scheduling information for each part of the airplane and its
engines, auxiliary power units, propellers, accessories,
instruments, and equipment that provides the recommended periods at
which they should be cleaned, inspected, adjusted, tested, and
lubricated, and the degree of inspection, the applicable wear
tolerances, and work recommended at these periods. However, the
applicant may refer to an accessory, instrument, or equipment
manufacturer as the source of this information if the applicant
shows that the item has an exceptionally high degree of complexity
requiring specialized maintenance techniques, test

equipment, or expertise. The recommended overhaul periods and
necessary cross reference to the Airworthiness Limitations section
of the manual must also be included. In addition, the applicant must
include an inspection program that includes the frequency and extent
of the inspections necessary to provide for the continued
airworthiness of the airplane.
    (2) Troubleshooting information describing probable
malfunctions, how to recognize those malfunctions, and the remedial
action for those malfunctions.
    (3) Information describing the order and method of removing and
replacing products and parts with any necessary precautions to be
taken.
    (4) Other general procedural instructions including procedures
for system testing during ground running, symmetry checks, weighing
and determining the center of gravity, lifting and shoring, and
storage limitations.
    (c) Diagrams of structural access plates and information needed
to gain access for inspections when access plates are not provided.
    (d) Details for the application of special inspection techniques
including radiographic and ultrasonic testing where such processes
are specified by the applicant.
    (e) Information needed to apply protective treatments to the
structure after inspection.
    (f) All data relative to structural fasteners such as
identification, discard recommendations, and torque values.
    (g) A list of special tools needed.
    (h) In addition, for level 4 airplanes, the following
information must be furnished--
    (1) Electrical loads applicable to the various systems;
    (2) Methods of balancing control surfaces;
    (3) Identification of primary and secondary structures; and
    (4) Special repair methods applicable to the airplane.

A23.4 Airworthiness limitations section.

    The Instructions for Continued Airworthiness must contain a
section titled Airworthiness Limitations that is segregated and
clearly distinguishable from the rest of the document. This section
must set forth each mandatory replacement time, structural
inspection interval, and related structural inspection procedure
required for type certification. If the Instructions for Continued
Airworthiness consist of multiple documents, the section required by
this paragraph must be included in the principal manual. This
section must contain a legible statement in a prominent location
that reads ``The Airworthiness Limitations section is FAA approved
and specifies maintenance required under Sec. Sec.  43.16 and 91.403
of Title 14 of the Code of Federal Regulations unless an alternative
program has been FAA approved.''

PART 35--AIRWORTHINESS STANDARDS: PROPELLERS

0
9. The authority citation for part 35 is revised to read as follows:

    Authority: 49 U.S.C. 106(f), 106(g), 40113, 44701-44702, 44704.

0
10. In Sec.  35.1, revise paragraph (c) to read as follows:

Sec.  35.1   Applicability.

* * * * *
    (c) An applicant is eligible for a propeller type certificate and
changes to those certificates after demonstrating compliance with
subparts A, B, and C of this part. However, the propeller may not be
installed on an airplane unless the applicant has shown compliance with
either Sec.  23.2400(c) or Sec.  25.907 of this chapter, as applicable,
or compliance is not required for installation on that airplane.
* * * * *

0
11. In Sec.  35.37, revise paragraph (c)(1) to read as follows:

Sec.  35.37   Fatigue limits and evaluation.

* * * * *
    (c) * * *
    (1) The intended airplane by complying with Sec.  23.2400(c) or
Sec.  25.907 of this chapter, as applicable; or
* * * * *

PART 43--MAINTENANCE, PREVENTIVE MAINTENANCE, REBUILDING, AND
ALTERATION

0
12. The authority citation for part 43 is revised to read as follows:

    Authority: 42 U.S.C. 7572; 49 U.S.C. 106(f), 106(g), 40105,
40113, 44701-44702, 44704, 44707, 44709, 44711, 44713, 44715, 45303.

0
13. In part 43, appendix E, revise the introductory text and paragraph
(a)(2) to read as follows:

Appendix E to Part 43--Altimeter System Test and Inspection

    Each person performing the altimeter system tests and
inspections required by Sec.  91.411 of this chapter must comply
with the following:
    (a) * * *
    (2) Perform a proof test to demonstrate the integrity of the
static pressure system in a manner acceptable to the Administrator.
For airplanes certificated under part 25 of this chapter, determine
that leakage is within the tolerances established by Sec.  25.1325.
* * * * *

PART 91--GENERAL OPERATING AND FLIGHT RULES

0
14. The authority citation for part 91 continues to read as follows:

    Authority: 49 U.S.C. 106(f), 106(g), 1155, 40101, 40103, 40105,
40113, 40120, 44101, 44111, 44701, 44704, 44709, 44711, 44712,
44715, 44716, 44717, 44722, 46306, 46315, 46316, 46504, 46506-46507,
47122, 47508, 47528-47531, 47534, articles 12 and 29 of the
Convention on International Civil Aviation (61 Stat. 1180), (126
Stat. 11).

0
15. In Sec.  91.205, revise paragraphs (b)(13) and (b)(14), and remove
and reserve paragraph (b)(16) to read as follows:

Sec.  91.205   Powered civil aircraft with standard category U.S.
airworthiness certificates: Instrument and equipment requirements.

* * * * *
    (b) * * *
    (13) An approved safety belt with an approved metal-to-metal
latching device, or other approved restraint system for each occupant 2
years of age or older.
    (14) For small civil airplanes manufactured after July 18, 1978, an
approved shoulder harness or restraint system for each front seat. For
small civil airplanes manufactured after December 12, 1986, an approved
shoulder harness or restraint system for all seats. Shoulder harnesses
installed at flightcrew stations must permit the flightcrew member,
when seated and with the safety belt and shoulder harness fastened, to
perform all functions necessary for flight operations. For purposes of
this paragraph--
    (i) The date of manufacture of an airplane is the date the
inspection acceptance records reflect that the airplane is complete and
meets the FAA-approved type design data; and
    (ii) A front seat is a seat located at a flightcrew member station
or any seat located alongside such a seat.
* * * * *
    (16) [Reserved]
* * * * *

0
16. In Sec.  91.313, revise paragraph (g) introductory text to read as
follows:

Sec.  91.313   Restricted category civil aircraft: Operating
limitations.

* * * * *
    (g) No person may operate a small restricted-category civil
airplane manufactured after July 18, 1978, unless an approved shoulder
harness or restraint system is installed for each front seat. The
shoulder harness or restraint system installation at each flightcrew
station must permit the flightcrew member, when seated and with the
safety belt and shoulder harness fastened or the restraint system
engaged, to perform all functions necessary for flight operation. For
purposes of this paragraph--
* * * * *

0
17. In Sec.  91.323, revise paragraph (b)(3) to read as follows:

Sec.  91.323   Increased maximum certificated weights for certain
airplanes operated in Alaska.

* * * * *
    (b) * * *
    (3) The weight at which the airplane meets the positive maneuvering
load factor n, where n=2.1+(24,000/(W+10,000)) and W=design maximum
takeoff weight, except that n need not be more than 3.8; or
* * * * *

0
18. In Sec.  91.531, revise paragraphs (a)(1) and (a)(3) to read as
follows:

Sec.  91.531   Second in command requirements.

    (a) * * *
    (1) A large airplane or normal category level 4 airplane, except
that a person may operate an airplane certificated under SFAR 41
without a pilot who is designated as second in command if that airplane
is certificated for operation with one pilot.
* * * * *
    (3) A commuter category airplane or normal category level 3
airplane, except that a person may operate those airplanes
notwithstanding paragraph (a)(1) of this section, that have a passenger
seating configuration, excluding pilot seats, of nine or less without a
pilot who is designated as second in command if that airplane is type
certificated for operations with one pilot.
* * * * *

PART 121--OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL
OPERATIONS

0
19. The authority citation for part 121 continues to read as follows:

    Authority: 49 U.S.C. 106(f), 106(g), 40103, 40113, 40119, 41706,
42301 preceding note added by Pub. L. 112-95, Sec. 412, 126 Stat.
89, 44101, 44701-44702, 44705, 44709-44711, 44713, 44716-44717,
44722, 44729, 44732; 46105; Pub. L. 111-216, 124 Stat. 2348 (49
U.S.C. 44701 note); Pub. L. 112-95, 126 Stat. 62 (49 U.S.C. 44732
note).

0
20. In Sec.  121.310, revise paragraph (b)(2)(iii) to read as follows:

Sec.  121.310   Additional emergency equipment.

* * * * *
    (b) * * *
    (2) * * *
    (iii) For a nontransport category turbopropeller powered airplane
type certificated after December 31, 1964, each passenger emergency
exit marking and each locating sign must be manufactured to have white
letters 1 inch high on a red background 2 inches high, be self-
illuminated or independently, internally electrically illuminated, and
have a minimum brightness of at least 160 microlamberts. The color may
be reversed if the passenger compartment illumination is essentially
the same. On these airplanes, no sign may continue to be used if its
luminescence (brightness) decreases to below 100 microlamberts.
* * * * *

PART 135--OPERATING REQUIREMENTS: COMMUTER AND ON DEMAND OPERATIONS
AND RULES GOVERNING PERSONS ON BOARD SUCH AIRCRAFT

0
21. The authority citation for part 135 continues to read as follows:

    Authority: 49 U.S.C. 106(f), 106(g), 41706, 40113, 44701-44702,
44705, 44709, 44711-44713, 44715-44717, 44722, 44730, 45101-45105;
Pub. L. 112-95, 126 Stat. 58 (49 U.S.C. 44730).

0
22. In Sec.  135.169, revise paragraphs (b) introductory text, (b)(6),
and (b)(7), and add paragraph (b)(8) to read as follows:

Sec.  135.169   Additional airworthiness requirements.

* * * * *
    (b) No person may operate a small airplane that has a passenger-
seating configuration, excluding pilot seats, of 10 seats or more
unless it is type certificated--
* * * * *
    (6) In the normal category and complies with section 1.(b) of
Special Federal Aviation Regulation No. 41;
    (7) In the commuter category; or
    (8) In the normal category, as a multi-engine certification level 4
airplane as defined in part 23 of this chapter.
* * * * *

    Issued under authority provided by 49 U.S.C. 106(f), 44701(a),
44703 and Pub. L. 113-53 (127 Stat. 584; 49 U.S.C. 44704 note) in
Washington, DC, on December 12, 2016.
Michael P. Huerta,
Administrator.
[FR Doc. 2016-30246 Filed 12-21-16; 4:15 pm]
 BILLING CODE 4910-13-P