Appendix A Table A-1. Terms and Definitions (continued)
Term Definition dB Decibel DER Designated Engineering Representative DFDR Digital Flight Data Recorder DG Directional Gyros DH Decision Height DME Distance Measuring Equipment ECAM Electronic Centralized Aircraft monitor EFCS Electronic Flight Control System EGT Exhaust Gas Temperature EICAS Engine Indicating and Crew Alerting System EMC Electromagnetic Compatibility EMI Electromagnetic Interference EPR Engine Pressure Ratio ESDU Engineering Sciences Data Unit F Fahrenheit F&R Function and Reliability FGS Flight Guidance System FMEA Failure Modes and Effects Analysis FMS Flight Management System FOD Foreign Object Damage FS Longitudinal Control (Stick) Force A-3
Appendix A Table A-1. Terms and Definitions (continued)
Term Definition FSB Flight Standardization Board FS/g Stick Force per g ft Foot or Feet FWC Flight Warning Computer g or G Acceleration Due to Gravity at the Earth’s Surface GLS GNSS Landing System GNSS Global Navigation Satellite System HF High Frequency HGS Head-Up Guidance System HQ Handling Qualities HQRM Handling Qualities Rating Method HSI Horizontal Situation Indicator HUD Head-Up Display Hz Hertz (cycles per second) IAS Indicated Airspeed ICAO International Civil Aviation Organization IFR Instrument Flight Rules IKE Initial Kinetic Energy ILS Instrument Landing System IMC Instrument Meteorological Conditions INS Inertial Navigation System IRS Inertial Reference System A-4
Appendix A Table A-1. Terms and Definitions (continued)
Term Definition ITT Interstage Turbine Temperature IVSI Instantaneous Vertical Speed Indicator KE Kinetic Energy lbs Pounds LF Low Frequency LFE Limit Flight Envelope LNAV Lateral Navigation LODA Letter of Design Approval M Mach Number MAC Mean Aerodynamic Chord MCS Master Caution System MCT Maximum Continuous Thrust MD Design Dive Mach MDA Minimum Descent Altitude MDF Demonstrated Flight Diving Mach MEL Minimum Equipment List MF Medium Frequency MFC Maximum Mach for Stability Characteristics MFD Multi-Function Display min Minute(s) MLRC Long Range Cruise Mach A-5
Appendix A Table A-1. Terms and Definitions (continued)
Term Definition MLS Microwave Landing System MMEL Master Minimum Equipment List MMO Maximum Operating Mach MSL Mean Sea Level MWS Master Warning System MUH Minimum Use Height N1 Rotational Speed of Low Pressure Compressor (Turbine Engine) N2 Rotational Speed of High Pressure Compressor (Turbine Engine) NAS National Airspace System NAV Navigate NM Nautical Mile(s) NFE Normal Flight Envelope OAT Outside Air Temperature OEW Operating Empty Weight OFE Operational Flight Envelope PA Public Address PFC Porous Friction Course PIO Pilot Induced Oscillation Q Dynamic Pressure R/A Radio Altimeter RFI Radio Frequency Interference A-6
Appendix A Table A-1. Terms and Definitions (continued)
Term Definition RPM Revolutions per Minute RMI Radio Magnetic Indicator RNAV Area Navigation RNP Required Navigation Performance RTO Rejected Takeoff RVP Reid Vapor pressure RVR Runway Visual Range SAS Stability Augmentation System SAT 1. Static Air Temperature
2. Satisfactory (when used with the handling qualities rating method) SATCOM Satellite Communications secs Seconds SELCAL Selective Calling System S/F Slow/Fast SR Special Regulation STC Supplemental Type Certificate STOL Short Takeoff and Landing SWC Stall Warning Computer TAT Total Air Temperature TAWS Terrain Awareness and Warning System TCAS Traffic Collision Avoidance System TCDS Type Certificate Data Sheet A-7
Appendix A Table A-1. Terms and Definitions (continued)
Term Definition TIA Type inspection Authorization TIR Type Inspection Report TOW Takeoff Warning TSO Technical Standard Order T/W Thrust-to-Weight Ratio UNSAT 1. Unsatisfactory
2. Failed V1 Maximum speed in the takeoff at which the pilot must take the first action (e.g., apply brakes, reduce thrust, deploy speed brakes) to stop the airplane within the accelerate-stop distance. It also means the minimum speed in the takeoff, following a failure of the critical engine at VEF, at which the pilot can continue the takeoff and achieve the required height above the takeoff surface within the takeoff distance.
V2 Takeoff safety speed V2MIN Minimum takeoff safety speed V35 Speed at a height of 35 feet above the takeoff surface VD Design diving speed VDF Demonstrated flight diving speed VEF Speed at which the critical engine is assumed to fail during takeoff VFC Maximum speed for stability characteristics VFE Maximum flap extended speed VFR Visual Flight Rules VG Vertical Gyros A-8
Appendix A Table A-1. Terms and Definitions (continued)
Term Definition VHF Very High Frequency VLE Maximum landing gear extended speed VLO Maximum landing gear operating speed VLOF Lift off speed VMC Visual Meteorological Conditions VMC Minimum control speed with the critical engine inoperative VMCA Minimum control speed in the air VMCG Minimum control speed on the ground VMCL Minimum control speed during approach and landing with all engines operating VMCL(1 out) Minimum control speed during approach and landing with one engine inoperative VMCL-2 Minimum control speed during approach and landing with one critical engine inoperative (for airplanes with three or more engines) VMCL-2(2 out) Minimum control speed during approach and landing with two engines inoperative (for airplanes with three or more engines) VMO Maximum operating limit speed VMU Minimum unstick speed VNAV Vertical Navigation VOR Very High Frequency Omnidirectional Range VORTAC Very High Frequency Omnidirectional Range Tactical Air Navigation VREF Reference landing speed VS Stalling speed or the minimum steady flight speed at which the airplane is controllable A-9
Appendix A Table A-1. Terms and Definitions (continued)
Term Definition VS0 Stalling speed or the minimum steady flight speed in the landing configuration VS1 Stalling speed or the minimum steady flight speed in a specific configuration VSR Reference stall speed VSR0 Reference stall speed in the landing configuration VSR1 Reference stall speed in a specific configuration VSW Speed at which the onset of natural or artificial stall warning occurs WAT Weight, Altitude, Temperature W/δ Weight/Delta Table A-2. Symbols and Definitions
Symbol Definition Δ Incremental change in value δ Ratio of atmospheric pressure at any altitude to the pressure at sea level max Maximum friction coefficient available between a tire and the runway surface A-10
05/04/18
AC 25-7D Appendix B APPENDIX B. FUNCTION AND RELIABILITY (F&R) TESTS
B.1 Explanation.
B.1.1 Section 21.35(b)(2) requires applicants for a type certificate (including an amended type certificate, supplemental type certificate (STC), or amended STC) to conduct all flight tests that the FAA finds necessary to determine whether there is reasonable assurance that the airplane, its components, and its equipment function properly (i.e., perform their intended function without introducing safety hazards) and are reliable (i.e., will continue to function properly in service).
Note: To obtain wider experience, manufacturers are encouraged to cooperate with operators in operating airplanes with provisional type certificates under service conditions.
B.1.2 However, the applicant must discontinue flight testing until appropriate corrective action has been taken, in accordance with § 21.35(e)(2), when it finds items of non-compliance with requirements that may make additional test data meaningless or that would make further testing unduly hazardous. The applicant must address any non-compliance with the functionality or reliability standards in the applicable airworthiness standards and any unsafe feature or characteristic identified during the test program prior to approval of the design under § 21.21(b)(1) and (2). Additional compliance demonstration testing and/or F&R testing may be necessary if the applicant introduces a design change.
B.1.3 Section 21.35(b)(2) applies to all type certification programs (except those covered under §§ 21.24 through 21.29), including those involving new type certificates, amended type certificates (including type design changes), STCs, and amended STCs.
B.2 Procedures.
The principal FAA flight test pilot for the project will act as coordinator of all flight activities during the official program, and that pilot (or a designated alternate) will participate in all flights. Other FAA personnel will not board the F&R airplane(s) during these activities unless authorized by the flight test pilot. The manufacturer’s pilot should be in command of all flights, but FAA pilots will fly the airplane to determine compliance with § 21.35(b)(2). Other FAA personnel (e.g., representatives of other divisions and specialists) will participate in the flight tests, when deemed necessary, to accomplish the purpose of the tests.
B.2.1 Test Time.
It is highly desirable that the FAA administer F&R test programs uniformly so that the program and flight time for similar projects will be approximately the same, regardless of which ACO administers the project. This can be difficult to achieve without establishing fixed test times that would be contrary to the FAA’s intent that § 21.35 (b)(2) be a performance-based standard. The applicant should use the following procedure as a guide for developing F&R test programs:
B-1
Appendix B B.2.1.1 For a new or changed turbine engine-powered airplane incorporating engines of a type not previously used on a type-certificated airplane, § 21.35(f)(1) requires an F&R test program of at least 300 hours.
(“Engines of a type not previously used on a type-certificated airplane” means engines of a new or changed type design that require a substantially complete investigation of compliance with the applicable regulations, regardless of whether a new engine type certificate was issued.) Though some F&R test requirements can be completed concurrently with certification testing (if relevant design conformity can be shown), experience has indicated the desirability of obtaining at least 150 hours of the minimum required 300 hours of F&R test time as dedicated F&R test time on a production configured airplane for these types of certification programs. However, § 21.35(f)(1) requires the applicant to perform a minimum of 300 hours of F&R time on a full complement of engines installed on the airplane that fully conform to the production configuration. To accomplish the intent of the reliability demonstration required by § 21.35(b)(2), the applicant must use the same full complement (single ship set) of engines for at least 300 airplane test hours.
B.2.1.2 For a new turbine engine-powered airplane (i.e., a new type certificate program) that is conventional with regard to complexity and design features, and does not incorporate “engines that have not been previously used on a type-certificated airplane” as defined above, the FAA has found that F&R can normally be proven by less than 300 hours of testing. The ACO can reduce the amount of required F&R test time below 300 hours by granting credit for certain types of component testing (see paragraph B.2.5.2 of this appendix) and for supplementary experience (see paragraph B.2.1.4.3 of this appendix). However, the test time may not be reduced below the minimum 150 hours required by § 21.35(f)(2). More than 150 hours of F&R testing may be necessary if difficulties are encountered or for unusual cases of complexity.
B.2.1.3 For airplanes incorporating design changes, the FAA can give full or partial credit for F&R testing performed previously on sufficiently similar configurations of that aircraft type. The FAA should require an amount of new dedicated F&R testing commensurate with the level of change made to the airplane design, the potential effect of the change on the F&R of the airplane, the amount of flight testing performed to show compliance with airworthiness requirements, and the configuration of the aircraft used in the flight testing performed to show compliance with airworthiness requirements. The FAA may choose to give the applicant credit, reducing the amount of dedicated F&R test time, for test time from the flight testing compliance demonstration for type certification, provided that:
The changed and potentially affected areas of the airplane conform to the production configuration, and B-2
Appendix B
The test activities are consistent with the intent of the F&R testing required for the design change.
B.2.1.4 When satisfactory supplementary experience gained from operators’ route proving tests; or from the applicant’s or operator’s ferry flights, customer demonstration flights, or training flights; is available and taken into account, the following allowances should be used as a guide and applied with judgment in reducing the official flight test time. However, in any case, the official F&R test program should provide sufficient time to accomplish the objective of paragraph B.1 in accordance with the procedures described in paragraphs B.2.5.3 and B.2.5.4.
1. Intensive Experience. When the allowance is based on the total time of any one airplane in airline crew training and similar intensive operations, two hours of such operation may be considered equivalent to one hour of official testing.
2. For Miscellaneous Experience. When the allowance is based on the total time of any one airplane, five hours of such experience may be considered equivalent to one hour of official testing.
3. Reduction for Supplementary Experience. Whenever a reduction of official test time is desired on the basis of supplementary experience, such experience should be adequately recorded and submitted to the responsible FAA aircraft certification office as described in paragraph B.2.6.2 of this appendix.
B.2.1.5 The FAA should only consider giving credit for F&R test activities or test time required under § 21.35(b)(2) for compliance demonstration testing performed under § 21.35(b)(1) when:
The changed and potentially affected areas of the airplane conform to the production configuration, and The test activities are consistent with the intent of the F&R testing determined to be required for the design change.
B.2.2 Test Airplane.
To facilitate completion of the type certification procedure, the applicant should use one airplane, in production configuration or equivalent, for the official F&R tests and use another airplane (or airplanes) for the compliance demonstration tests for type certification. In this case, the test time on at least one airplane would be sufficient to accomplish the reliability demonstration objective of § 21.35(b)(2). That is, the applicant should perform the reliability demonstration (normally either 150 or 300 hours, but potentially longer if problems are discovered) on a single airplane as implied by § 21.35(c). All engines of the F&R test airplane are required, in accordance with § 21.35(f)(1), to fully conform to the production configuration for all credited F&R test time. This engine conformity requirement was specifically discussed in the preamble to amendment 21-40.
B-3
Appendix B
B.2.3 Modified Types.
The procedure outlined in paragraph B.2.4 below applies to new type designs. When a design employs components (parts) identical to those used in previous designs, the applicant may receive credit for the supplementary experience available for such components. When a design is modified (e.g., one certification program covers several versions of the same basic type with different engines, propellers, etc.), the modified features and components should be rechecked in accordance with paragraph B.2.5.6 below.
B.2.4 Test Program.
The project engineers of the responsible FAA ACO will propose guidelines for developing an F&R test program at the preflight type board meeting (prior to commencement of FAA certification flight tests) and coordinate this with the airplane manufacturer. Near the conclusion of the type certification tests, the FAA certification engineers will again meet with the manufacturer to review the experience gained in those tests, review changes made in the design, consider any additional supplementary experience, and revise the proposed F&R test program accordingly. In application, there is generally considerable overlap of the certification and F&R test programs, thus making a definite transition point indiscernible.
B.2.5 Planning and Execution of Test Program.
The following points should be considered:
B.2.5.1 The test program should be sufficiently well planned to enable its execution in an efficient manner without overlooking important items.
Documentation should focus on the test objective(s) but does not necessarily require the type of detail maintained for type certification testing. The FAA project engineers will review the design features and equipment (appliances) with respect to the general objective and prepare a list showing:
Components and systems to be checked in accordance with the procedures described in the paragraph B.2.5.4 below.
A brief description of the operations to be performed, where these are not obvious (referencing any necessary operating instructions).
Special checks or likely critical conditions.
Estimated flight time required.
B.2.5.2 Allowance may be made for those functional tests whose requirements are covered by part 25 type certification tests. Allowance may also be made for qualification-type testing of new features and equipment; however, the flight test program should be planned to determine the adequacy of these tests and the accuracy of the simulated operating environment (e.g., to determine whether the actual environmental conditions such as temperature variation, etc., are covered by the test simulations) when these B-4