AC 20-124, “Water Ingestion Testing for Turbine Powered Airplanes,” September 30, 1985.
AC 20-128A, “Design Considerations for Minimizing Hazards Caused by Uncontained Turbine Engine and Auxiliary Power Unit Rotor Failure,” March 25, 1997.
AC 20-131A, “Airworthiness Approval of Traffic Alert and Collision Avoidance Systems (TCAS II) and Mode S Transponders,” March 29, 1993.
AC 20-136, “Protection of Aircraft Electrical/Electronic Systems Against the Indirect Effects of Lightning,” March 5, 1990.
AC 20-138A, “Airworthiness Approval of Global Navigation Satellite System (GNSS) Equipment,” December 22, 2003.
AC 20-146, “Methodology for Dynamic Seat Certification by Analysis for Use in Part 23, 25, 27, and 29 Airplanes and Rotorcraft,” May 19, 2003.
AC 21-16D, “RTCA Document DO-160D,” July 21, 1998.
AC 21-25A, “Approval of Modified Seating Systems Initially Approved Under a Technical Standard Order,” June 3, 1997.
AC 21-34, “Shoulder Harness-Safety Belt Installations,” June 4, 1993.
AC 23-2, “Flammability Tests,” August 20, 1984.
AC 23-18, “Installation of Terrain Awareness and Warning System (TAWS) Approved for Part 23 Airplanes,” June 14, 2000.
AC 23-19, “Airframe Guide for Certification of Part 23 Airplanes,” January 27, 2003.
AC 23.143-1, “Ice Contaminated Tailplane (ICTS) Stall,” December 20, 2001.
AC 23.562-1, “Dynamic Testing of Part 23 Airplane Seat/Restraint Systems and Occupant Protection,” June 22, 1989.
AC 23.1309-1C, “Equipment, Systems, and Installations in Part 23 Airplanes,” March 12, 1999.
AC 23.1311-1A, “Installation of Electronic Displays in Part 23 Airplanes,” March 12, 1999.
AC 23.1419-2C, “Certification of Part 23 Airplanes for Flight in Icing Conditions,” July 21, 2004.
AC 25-11, “Transport Category Airplane Electronic Display Systems,” July 16, 1987.
AC 90-79, “Recommended Practices and Procedures for the Use of Electronic Long- Range Navigation,” July 14, 1980.
AC 120-31A, “Operational and Airworthiness Approval of Airborne Omega Radio Navigation Systems as a Means of Updating Self-Contained Navigation Systems,” April 21, 1977.
AC 120-37, “Operational and Airworthiness Approval of Airborne Omega Radio Navigation Systems as a Sole Means of Overwater Long Range Navigation,” October 10, 1978.
AC 121-13, and Change 2, “Self-Contained Navigation Systems (Long Range),” December 21, 1970.
Copies of current publications of the following “for sale” ACs may be purchased from the Superintendent of Documents, P. O. Box 371954, Pittsburgh, PA 15250-7954; make check or money order payable to the Superintendent of Documents:
AC 20-88A, “Guidelines on the Marking of Aircraft Powerplant Instruments (Displays),” May 21, 1986.
AC 20-101C, “Airworthiness Approval of Omega/VLF Navigation Systems for Use in the U.S. National Airspace System (NAS) and Alaska,” September 12, 1988.
AC 21.303-2H, “Parts Manufacturer Approvals – 1992 (Microfiche),” October 13, 1992 (Microfiche).
AC 23-16A, “Powerplant Guide for Certification of Part 23 Airplanes and Airships,” February 23, 2004.
AC 23-8B, “Flight Test Guide for Certification of Part 23 Airplanes,” August 14, 2003.
AC 43.13-1B, Change 1, “Acceptable Methods, Techniques, and Practices⎯Aircraft Inspection and Repair,” September 27, 2001.
AC 43.13-2A, “Acceptable Methods, Techniques, and Practices⎯Aircraft Alterations,” January 1, 1977.P-8110-2, Change 2, “Airship Design Criteria,” February 6, 1995
NOTE 1: Republishing these documents, as a part of this AC, was not considered to be the best utilization of FAA resources.
b. Industry Documents 4
(1) To obtain a copy of the TSOs, write to the U.S. Department of Transportation, Subsequent Distribution Office, Ardmore East Business Center, 3341 Q 75th Avenue, Landover, MD 20785, or from the internet at http://www.faa.gov/certification/aircraft/.
TSO-C9c, “Automatic Pilots,” September 15, 1960.
TSO-C62d, “Tires,” September 7, 1990.
TSO-C22g, “Safety Belts,” March 5, 1993.
TSO-C26c, “Aircraft Wheels and Wheel-Brake Assemblies, with Addendum I,” May 18, 1984.
TSO-C39b, “Aircraft Seats and Berths,” April 17, 1987.
TSO-C55, “Fuel and Oil Quantity Instruments (Reciprocating Engine Aircraft),” April 1, 1959.
TSO-C114, “Torso Restraint Systems,” March 27, 1987.
TSO-C151b, “Terrain Awareness and Warning System,” December 17, 2002.
(2) The RTCA documents listed below are available from RTCA, Inc., Suite 805, 1828 L Street, NW, Washington, DC 20036:
RTCA/DO-160D, “Environmental Conditions and Test Procedures for Airborne Equipment,” July 29, 1997.
RTCA/DO-178B, “Software Considerations in Airborne Systems and Equipment Certification,” December 1, 1992.
(3) The documents listed below are available from the Society of Automotive Engineers (SAE), Inc., 400 Commonwealth Drive, Warrendale, PA 15096:
SAE Aerospace Recommended Practice (ARP), ARP 597C, “Wheels and Brakes, Supplementary Criteria for Design Endurance⎯Civil Transport Aircraft,” April 24, 1991.
SAE ARP 813A, “Maintainability Recommendations for Aircraft Wheel and Brake Design,” February 1, 1995.
SAE ARP 1619, “Replacement and Modified Brakes and Wheels,” March 1, 2001.
SAE Aerospace Information Report (AIR) 1064, “Brake Dynamics,” January 1, 1997.
SAE Aerospace Standard AS1145, “Aircraft Brake Temperature Monitor System (Btms),” February 1, 1998.
SAE J384, “Motor Vehicle Seat Belt Anchorages-Test Procedure,” June 9, 1994.
SAE Recommended Practice, June 2004 SAE Handbook, Volume 2, pages 33.08-33.09.
SAE ARP 5412, “Aircraft Lightning Environment and Related Test Waveforms,” November 1, 1999.
SAE ARP 5413, “Certification of Aircraft Electrical/Electronic Systems for the Indirect Effects of Lightning,” (it is being incorporated into an AC), November 1, 1999.
SAE ARP 5414, “Aircraft Lightning Zoning,” December 1, 1999.
SAE ARP 5415, “Users Manual for Certification of Aircraft Electrical/Electronic Systems for the Indirect Effects of Lightning,” May 14, 2002.
SAE ARP 5475, “Abuse Load Testing for In-Seat Deployable-Video Systems,” March 1, 2001.
SAE ARP 5577, “Aircraft Lightning Direct Effects Certification,” September 30, 2002.
(4) The Underwriters Laboratories (UL), Inc., document listed below can be obtained from Global Engineering Documents, 15 Inverness Way East, Englewood, CO 80112:
UL 1418, “Cathode Ray Tubes,” September 6, 1996.
(5) General Aviation Manufacturers Association (GAMA). GAMA publication can be purchased from the GAMA web site, http://www.gama.aero/pub:
GAMA publication No. 10, “Recommended Practices and Guidelines for Part 23 Cockpit/Flight Deck Design,” dated September 2000.
c. National Aeronautics and Space Administration (NASA) document
American Society for Testing and Materials (ASTM) Manual 36, “Safe Use of Oxygen and Oxygen Systems, Guidelines for Oxygen System Design, Materials Selection, Operations, Storage, and Transportation,” dated 2000, may be purchased from the ASTM, 100 Barr Harbor Drive, Post Office Box C700, West Conshohocken, PA 19428- 2959.
d. European Aviation Safety Agency (EASA) Documents
EASA Certification Specifications (CS-23) and guidance materials, Acceptable Means of Compliance, (AMCs), are available from the EASA website at www.easa.eu.int/certspecs_en.html
7. RELATED 14 CFR, PART 23 REGULATIONS
23.75 Landing distance
23.141 Flight Characteristics- General
23.143 Controllability and Maneuverability- General
23.145 Longitudinal control
23.201 Wings level stall
23.231 Ground and Water Handling Characteristics- Longitudinal stability and control
23.233 Directional stability and control
23.253 High speed characteristics
23.303 Factor of safety
23.305 Strength and deformation
23.307 Proof of structure
23.335 Design airspeeds
23.345 High lift devices
23.351 Yawing conditions
23.365 Pressurized cabin loads
23.395 Control system loads
23.397 Limit control forces and torques
23.405 Secondary control system
23.473 Ground load conditions and assumptions
23.477 Landing gear arrangement
23.479 Level landing conditions
23.481 Tail down landing conditions
23.483 One-wheel landing conditions
23.485 Side load conditions
23.493 Braked roll conditions
23.505 Supplementary conditions for ski-planes
23.521 Water load conditions
23.561 Emergency Landing Conditions- General
23.562 Emergency landing dynamic conditions
23.601 Design and Construction- General
23.603 Materials and workmanship
23.613 Material strength properties and design values
23.655 Control Surfaces- Installation
23.955 Fuel flow
23.959 Unusable fuel supply
23.961 Fuel system hot weather operation 7
23.991 Fuel pumps
23.993 Fuel system lines and fittings
23.995 Fuel valves and controls
23.997 Fuel strainer or filter
23.1019 Oil strainer or filter
23.1121 Exhaust System- General
23.1123 Exhaust system
23.1182 Nacelle areas behind firewalls
23.1183 Lines, fittings, and components
23.1191 Firewalls
23.1203 Fire detector system
23.1505 Airspeed limitations
23.1525 Kinds of operation
23.1527 Maximum operating altitude
23.1529 Instructions for Continued Airworthiness
23.1541 Markings and Placards- General
23.1543 Instrument markings: General
23.1545 Airspeed indicator
23.1547 Magnetic direction indicator
23.1549 Powerplant and auxiliary power unit instruments 23,1551 Oil quantity indicator
23.1553 Fuel quantity indicator
23.1555 Control markings
23.1557 Miscellaneous markings and placards
623.1559 Operating limitations placard
23.1581 Airplane Flight Manual and Approved Manual material- General
23.1583 Operating limitations
23.1585 Operating procedures Appendix F to Part 23 Test Procedure (Flammability)
SYSTEMS AND EQUIPMENT GUIDE FOR CERTIFICATION OF PART 23 AIRPLANES
Subpart D—Design and Construction
CONTROL SYSTEMS
23.671 General
No FAA policy is available as of September 30, 2003. EASA AMC 23.671 is acceptable for FAA certification.
This rule was adopted on February 1, 1965 as a recodification of Civil Air Regulations (CAR), CAR 3.335.
23.672 Stability augmentation and automatic and power-operated systems
There is no corresponding rule in CAR 3 or the Airship Design Criteria.
Amendment 23-45 and Subsequent
This rule is applicable only if the system is required to show compliance with the flight characteristic requirements of part 23.
A proposed revision to NPRM 90-18 explains this amendment as follows: “This proposal would provide criteria for approval of those stability augmentation, automatic, and power-operated systems whose performance is essential to flight safety. The proposed § 23.672 is similar to § 5.672 and, as part 25, the warning system requirement relating to control system activation is not intended to preclude installing tactile warning devices, such as control system shakers activated independently for other purposes.”
NOTE 2: Section 5.672 in above quote is incorrect. It should be § 25.672.
This requirement would not apply to a simple downspring or a bobweight stability device as affirmed by Final Rule, Docket 26269.
23.673 Primary flight controls
No policy available as of September 30, 2003.
The corresponding rule in CAR 3 is CAR 3.336.
23.675 Stops
No policy available as of September 30, 2003.
The corresponding rule in CAR 3 is CAR 3.340.
23.677 Trim systems
The corresponding rule in CAR 3 is CAR 3.337.
The corresponding rule in the Airship Design Criteria, FAA-P-8110-2, Change 2, is section 4.16.
Original Issue and Subsequent
The trim system should prevent inadvertent, improper or abrupt trim operation. The direction of trim movement and its relation to its range of adjustment should be designed to prevent confusion.
Trim devices should be designed to continue normal operation with one failure of any connecting or transmitting element in the primary flight control system for
(1) longitudinal trim in a single-engine airplane, and (2) longitudinal and directional trim in multiengine airplanes.
Amendment 23-7 and Subsequent
The amendment requires there be adequate control for safe flight and landing (rather than to “continue normal operation”) using the trim devices following the failure of a connecting/transmitting element in the primary controls. Thus, the control system element failure must not cause a failure of the trim system.
Failures of the trim system must not prevent safe flight and landing.
This amendment is clarified by Final Rule, Docket 8083 as follows: “The notice proposed to amend § 23.677 to make it clear that operation of the trim system may not be dependent upon the primary control system and that failures of the primary control system may not prevent safe flight and landing. Comments were received objecting to the proposal on the ground that it exceeded the part 25 requirements for transport category airplanes, and that it would improperly and undesirably change trim response and make compliance tests extremely hazardous. The FAA does not agree. The trim requirement is merely one of a number of control system requirements that must be considered as a total requirement. There is, therefore, no comparison between individual provisions in parts 23 and 25. Service experience with existing airplanes does not indicate that the proposal will improperly and undesirably change trim response or that compliance testing will be hazardous.
Furthermore, trim response equal to primary flight control response will not necessarily be needed to comply with the proposal. All that is required is that there be adequate control for safe flight and landing.”
Amendment 23-34 and Subsequent
Section 23.677(d) was added by Amendment 23-34 was only applicable to commuter category airplanes.
Probable powered trim runaways should be demonstrated for all part 23 airplanes so equipped. See AC 23-8B, “Flight Test Guide for Certification of part 23 Airplanes,” for the procedure.
Even if trim runaways have been determined to be unlikely using the guidance in AC
23.1309-1C, “Equipment, Systems, and Installations in Part 23 Airplanes,” appropriate trim runaway demonstrations in all axes are required to demonstrate the airplane has no unsafe features. The FAA has accepted demonstration of controlrestrained trim runaways during malfunction testing for systems without a monitor/limiter regardless of the reliability and those with a monitor/limiter whose reliability is less than unlikely. However, the FAA has determined this procedure is not acceptable in itself for failure conditions shown to be less than unlikely. To allow expansion of the 0 to 2g envelope, as specified in AC 23-8B, the FAA suggests a test procedure that incorporates both control restrained and unrestrained errors. The following test matrix considers the probability of trim runaways, high airframe limit loads, control stick/wheel configuration and absence of an autopilot system. Because rudder trim can be adjusted without the pilot directly in the control loop (that is, feet on the floor), restrained runaways for rudder trim are not considered acceptable. (See Table 1).
TABLE 1. TRIM SYSTEMS REQUIREMENTS
M aximum Maximum Force M aximum Axis Time Load(g) Attitude (restrained and Rate of Force (unrestrained) Change unrest rained) C hange (unrestrained) (restrained) __________________________________________________________________________________ Pitch recognition structural +/-45 degrees 60 pounds 20 pounds/sec +3 seconds limits NTE
3.5g __________________________________________________________________________________ Roll recognition structural +/-90 degrees 30 pounds 10 pounds/sec +3 seconds limits __________________________________________________________________________________ Yaw recognition structural +/-30 degrees 150 pounds N/A +3 seconds limits (unrestrained only)
1. Restrained means the pilot is in the control loop (hands on) and unrestrained means the pilot is not in the control loop (hands off).
2. Trim systems with a monitor/limiter will be tested at a magnitude just below that required for monitor/limiter trip.
3. NTE is Not to Exceed.