(3) Testing should be conducted to verify that the reverser efflux does not have a detrimental effect on the powerplant installations. Items to be considered include:
(a) Foreign object damage (FOD);
(b) Effects on engine cooling;
(c) Inlet flow distortion;
(d) Re-ingestion of exhaust gases; and
(e) Any effects on engine mounted accessories.
(4) Testing should be conducted to verify that the reverser efflux does not have a detrimental effect on other airplane systems such as air conditioning system inlets, APU inlets and exhausts, overboard drains, etc.
(5) It should be verified that cockpit and cabin air will not be contaminated.
NOTE: 2. It is acceptable to have a limitation prohibiting the operation of the air conditioning packs during reverse thrust b acking to avoid cockpit and cabin air contamination.
(6) Reverse thrust backing demonstrations should be conducted to evaluate the associated procedures. These demonstrations should be conducted at:
(a) Maximum ramp weight with the c.g. at the aft limit, and
(b) Any other weight that may be critical with the c.g. at the aft limit.
(7) The reverse thrust backing demonstrations of paragraph (6), above, should be evaluated to determine:
(a) The degree of aft pitching moment, including its effect on nose wheel steering;
(b) The effect of inadvertent heavy/emergency braking action;
(c) Adequate cockpit visibility and ground crew function;
(d) The adequacy of procedures for transitioning from reverse to forward thrust;
(e) The effect of thrust asymmetry due to failure of an engine to enter reverse, or recover forward thrust mode;
(f) The effects of low tire pressures;
(g) The effect of ramp slope and surface condition;
(h) The effects of ambient atmospheric temperature; and
(i) The effect of flap/slat configuration.
Appendix 1 A1-1 Appendix 1
Acronyms and Abbreviations
Acronym/ Definition Abbreviation
AC advisory circular ACARS aircraft communications addressing and reporting system ACO aircraft certification office ACN aircraft classification number ADC air data computer ADF automatic direction finder ADI attitude director indicator ADQ adequate AEO all-engines-operating AFM airplane flight manual AGL above ground level AHRS attitude and heading reference system AOA angle of attack A-PC airplane-pilot coupling APU auxiliary power unit ARSR air route surveillance radar ARTCC air route traffic control center ASR airport surveillance radar ATA Air Transport Association ATC air traffic control ATCRBS air traffic control radar beacon system ATS automatic throttle system ATT REF attitude reference ATTCS automatic takeoff thrust control system C Celsius CAR civil air regulations
Appendix 1 A1-2 CAS calibrated airspeed CAT category CAWS central aural warning system CBR California bearing ratio CDL configuration deviation list CDU cockpit display unit CFR Code of Federal Regulations
c.g. center of gravity CL lift coefficient CMM component maintenance manual CN yawing moment coefficient COM communications CON controllable CRT cathode ray tube CVR cockpit voice recorder CWS control wheel steering Δ incremental change in value δ ratio of atmospheric pressure at any altitude to the pressure at sea level dB decibel 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 ELT emergency locator transmitter EMC electromagnetic compatibility EMI electromagnetic interference EPR engine pressure ratio
Appendix 1 A1-3 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 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 GNSS global navigation satellite system GPWS ground proximity warning system HF high frequency HGS head up guidance system HQ handling qualities HSI horizontal situation indicator HQRM handling qualities rating method HUD head up display Hz cycles per second IAS indicated airspeed ICAO International Civil Aviation Organization IKE initial kinetic energy ILS instrument landing system IMC instrument meteorological conditions INS inertial navigation system IRS inertial reference system ITT interstage turbine temperature IVSI instantaneous vertical speed indicator KE kinetic energy
Appendix 1 A1-4 LF low frequency LFE limit flight envelope LNAV lateral navigation M Mach number MAC mean aerodynamic chord MC master caution MCS master caution system MCT maximum continuous thrust MDA minimum descent altitude MEL minimum equipment list MFD multi-function display MF medium frequency Min. minutes min. minute(s) MLRC long range cruise Mach MLS microwave landing system MMEL master minimum equipment list MW master warning MWS master warning system max maximum friction coefficient available between a tire and the runway surface 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
Appendix 1 Change 1 A1-5 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
r.p.m. or 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 SAAAR special aircraft and aircrew authorization required SAS stability augmentation system SAT static air temperature, or satisfactory (when used with the handling qualities rating system) 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 TCAS traffic collision avoidance system TIA type inspection authorization
Appendix 1 Change 1 A1-6 TIR type inspection report TOW takeoff warning system TSO technical standard order T/W thrust-to-weight ratio UNSAT Unsatisfactory or 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/MD design diving speed VDF/MDF demonstrated flight diving speed VEF speed at which the critical engine is assumed to fail during takeoff VFC/MFC maximum speed for stability characteristics VFE maximum flap extended speed VFR visual flight rules VG vertical gyros 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
Appendix 1 Change 1 A1-7
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/MMO maximum operating limit speed VMU minimum unstick speed VNAV vertical navigation VOR very high frequency omnidirectional range VORTAC very high frequency omnidir ectional range tactical air navigation VREF reference landing speed VS stalling speed or the minimum steady flight speed at which the airplane is controllable 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
Appendix 2 A2-1 Appendix 2
Function and Reliability Tests - § 21.35(b)(2)
1. Explanation.
a. In order to satisfactorily accomplish the objectives concerning additional flight tests and the extent thereof, the Administrator deems it necessary that:
(1) A comprehensive and systematic check be made, in flight, of the operation of all components to determine whether they “function properly” (i.e., perform their intended function without introducing safety hazards).
(2) Sufficient FAA test experience, and supplementary experience gained from operators’ route proving tests, should be obtained and evaluated to give reasonable assurance that the airplane is “reliable” (i.e., should continue to function properly in service).
NOTE: In order to obtain wider experience, manufacturers are encouraged to cooperate with airlines or other responsible operators in operating airplanes with provisional type certificates under service conditions.
(3) Appropriate corrective action be taken when the need therefore is determined under subparagraphs (1) and (2) of this paragraph.
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 function and reliability (F & R) airplane(s) during these activities, particularly in regard to flight plans and procedures, 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.
a. Test Time . It is highly desirable that function and reliability test programs be administered uniformly so that the program and flight time for a given project would be approximately the same, regardless of which FAA ACO administered the project. This is difficult to achieve without establishing fixed arbitrary test times, which would obviously be contrary to the intent of § 21.35 (b)(2). The following procedure, which permits considerable flexibility, is therefore established as guidance for administering F & R test programs:
(1) For a turbine engine-powered airplane incorporating engines of a type not previously certificated, § 21.35(f)(1) requires an F & R test program of at least 300 hours. This 300 hour minimum may also be applied to a complex new airplane model (e.g., an airplane with an electronic flight control system (fly by wire)). Though some F & R test requirements can be completed concurrently with certification testing (if relevant design conformity can be shown),
Appendix 2 A2-2 experience has indicated the desirability of obtaining at least 150 hours on a production configured airplane. For a previously certificated airplane, the F & R program requirement should be commensurate with the modifications or changes.
(2) When supplementary experience is not taken into account, and the airplane is conventional with regard to complexity and design features and does not incorporate engines that have not been previously certificated (including derivative engines), it has been found that function and reliability tests can be performed within 300 hours. This time may be reduced if credit is granted for certain types of component testing (see paragraph 2e(2) of this Appendix) and for supplementary experience (see paragraph 2a(3)(c) of this Appendix). However, it may be necessary to increase the 150-hour minimum F & R test requirement of § 21.35(f)(2) if difficulties are encountered or for unusual cases of complexity.
(3) When satisfactory supplementary experience 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 1a(2) in accordance with the procedures described in paragraphs 2e(3) and (4).
(a) For 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.
(b) 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.
(c) 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 2f(2) of this Appendix.
b. Test Airplane . To facilitate completion of the type certification procedure, one airplane, in production configuration or equivalent, should be used for the official functional and reliability tests while another airplane (or airplanes) is used for the routine-type tests. In this case, the test time on at least one airplane would be sufficient to accomplish the objective of paragraph 1a(2) of this appendix.
c. Modified Types . The procedure outlined in paragraph d., below, applies to new type designs. When a design employs components (parts) identical to those used in previous designs, credit may be given for the supplementary experience available for such components. When a design is modified (e.g., several versions of the same basic type with different engines, propellers, etc.), the modified features and components should be rechecked in accordance with paragraph 2e(6), below.
Appendix 2 A2-3
d. 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.
e. Planning and Execution of Test Program . The following points should be considered:
(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:
(a) Components and systems to be checked in accordance with the procedures described in the below paragraph 2e(4).
(b) A brief description of the operations to be performed, where these are not obvious (referencing any necessary operating instructions).
(c) Special checks or likely critical conditions.
(d) Estimated flight time required.
(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 may be critical, and to determine whether the installation and connected systems are satisfactory. This does not imply that flight tests must be conducted under the most severe outside air temperatures likely to be encountered in service. It should normally be possible to determine the effects of extreme outside temperatures on local temperatures by extrapolation or by suitable correction factors. The FAA project engineers will then make a consolidated estimate of the total flight time required, allowing for overlapping, and adjust this in accordance with the “Test Time” outlined in the above paragraph 2a.
(3) This program will be arranged to permit the principal FAA flight test pilot to become thoroughly familiar with the operational aspects of the airplane in its anticipated service environment.
(4) All components of the airplane should be intensively operated and studied under all operating conditions expected in service and obtainable within the time and geographical