Circular Advisory

459 Pages·2005·3.34 MB·English

Advisory
U.S. Department
of Transportation
C i r c u l a r

Federal Aviation
Administration

AC 25-7A

DATE: 3/31/98

FLIGHT TEST GUIDE
FOR CERTIFICATION OF
TRANSPORT CATEGORY AIRPLANES
Subject: FLIGHT TEST GUIDE FOR Date: 6/3/99 AC No: 25-7A
CERTIFICATION OF TRANSPORT Initiated By: ANM-110 Change: 1
CATEGORY AIRPLANES

1. PURPOSE. This change provides updated guidance material to ensure consistent application
of certain airworthiness requirements adopted by recent amendments to 14 CFR part 25.
Changed material is indicated in the margins by asterisks and at the top of each changed page
with the change number and date. New material on pages 80-1 through 80-28 is indicated by the
change number and date only. Some text, although not changed, has been rearranged to
accommodate new material.

2. PRINCIPAL CHANGES.

a. New guidance regarding an acceptable means of compliance with the wet runway and
worn brake requirements adopted by Amendment 25-92, “Improved Standards for Determining
Rejected Takeoff and Landing Performance.”

b. Additional guidance regarding criteria for locating the gate when the airplane has multiple
go-around configurations, for compliance with the gate design requirements adopted by
Amendment 25-98, “Revision of Gate Requirements for High-Lift Device Controls.”

PAGE CONTROL CHART

Remove Pages Dated Insert Pages Dated
iii thru x 3/31/98 iii thru x 6/3/99
71 thru 105 3/31/98 71 thru 106 6/3/99
129 thru 148 3/31/98 129 thru 149 6/3/99
283 thru 300 3/31/98 283 thru 301 6/3/99

/s/ John J. Hickey
Acting Manager, Transport Airplane Directorate
Aircraft Certification Service
Subject: FLIGHT TEST GUIDE FOR Date: 3/31/98 AC No: 25-7A
CERTIFICATION OF TRANSPORT Initiated By: ANM-110 Change:
CATEGORY AIRPLANES

1. PURPOSE. This revised advisory circular (AC) provides updated guidance for the flight test
evaluation of transport category airplanes. These guidelines provide an acceptable means of
demonstrating compliance with the pertinent regulations of 14 CFR part 25. The methods and
procedures described herein have evolved through many years of flight testing of transport
category airplanes and, as such, represent current certification practice. Like all AC material,
these guidelines are not mandatory and do not constitute regulations. They are derived from
previous FAA experience in finding compliance with the airworthiness requirements and
represent methods and procedures found to be acceptable by that experience. Although
mandatory terms such as “shall” and “must” are used in this AC, because the AC method of
compliance is not in itself mandatory, these terms apply only to applicants who seek to
demonstrate compliance by use of the specific methods described in this AC.

2. CANCELLATION. AC 25-7, “Flight Test Guide for Certification of Transport Category
Airplanes,” dated April 9, 1986.

3. BACKGROUND. Since AC 25-7 was released on April 9, 1986, it has been the primary
source of guidance for flight test methods and procedures to show compliance with the
regulations contained in subpart B of part 25, which are related to airplane performance and
handling characteristics. For certification flight testing to show compliance with other part 25
regulations, Order 8110.8, “Engineering Flight Test Guide for Transport Category Airplanes,”
provided guidance for internal FAA use in determining acceptable means of compliance. Order
8110.8, as revised on September 26, 1974, has been subject to five change updates to reflect
significant policy changes; the last change being the removal of the subpart B-related material
concurrent with the original release of AC 25-7. Order 8110.8 reflected the policy in place when
Amendment 25-29 to part 25 was adopted, and the original release of AC 25-7 reflected an
Amendment 25-59 time frame. Part 25 has been amended significantly since the two referenced
documents were last revised and, likewise, guidance and policy have changed in many areas as
experience has been gained. During this time period, many advances in technology have also
taken place that require new or modified test techniques. This revision updates the original AC
to incorporate the latest policy and guidance material applicable to all sections of part 25. The
material related to regulations outside of subpart B supersedes that contained in Order 8110.8,
which has been cancelled accordingly upon issuance of this AC.
AC 25-7A 3/31/98
4. APPLICABILITY. These methods and procedures are promulgated, in the interest of
standardization, for use during all transport category airplane flight test certification activities.
This material is not to be construed as having any legal status and must be treated accordingly.
The procedures set forth herein are one acceptable means of compliance with applicable sections
of part 25. Any alternate means proposed by the applicant should be given due consideration.
Applicants are encouraged to use their technical ingenuity and resourcefulness in order to
develop more efficient and less costly methods of achieving the objectives of Part 25. Since
these methods and procedures are only one acceptable means of compliance, individuals should
be guided by the intent of the methods provided in this AC. As deviations from the methods and
procedures described in this AC may occur, FAA certification personnel will coordinate what
they consider to be major deviations with the Transport Standards Staff (ANM-110) of the
Transport Airplane Directorate. If in their judgment, however, a deviation is considered to be
minor, coordination with ANM-110 may not be necessary.

5. RELATED PUBLICATIONS. Certification personnel should be familiar with FAA Order
8110.4A, “Type Certification Process,” and FAA Order 8100.5, “Aircraft Certification
Directorate Procedures.” In this AC, reference is made to other FAA advisory circulars that
provide guidance on various aspects of type certification and supplemental type certification.

/s/ Ronald T. Wojnar
Manager, Transport Airplane Directorate
Aircraft Certification Service

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Chg. 1
CONTENTS

Paragraph Page No.

CHAPTER 1. GENERAL

1. FAR 25.1 Applicability [RESERVED] 1
2. FAR 25.2 Special Retroactive Requirements [RESERVED] 1

CHAPTER 2. FLIGHT

Section 1. GENERAL

3. FAR 25.21 Proof of Compliance.................................................................31
Figure 3-1 Weight Tolerance Limits..........................................................33
Figure 3-2 Equivalent Weight Extrapolation..............................................34
Figure 3-3 Test Parameters That Normally Can Be Corrected...................35
Figure 3-4 Wind Profile Variation..............................................................36
4. FAR 25.23 Load Distribution Limits [RESERVED]..................................42
5. FAR 25.25 Weight Limits [RESERVED]...................................................42
FAR 25.27 Center of Gravity Limits [RESERVED]...................................42
6. FAR 25.29 Empty Weight and Corresponding Center
of Gravity [RESERVED]..........................................................42
7. FAR 25.31 Removable Ballast [RESERVED]............................................42
8. FAR 25.33 Propeller Speed and Pitch Limits..............................................43

Section 2. PERFORMANCE

9. FAR 25.101 General......................................................................................71
FAR 25.103 Stalling Speed (see paragraph 29)
10. FAR 25.105 Takeoff......................................................................................71
FAR 25.107 Takeoff Speeds..........................................................................71
11. FAR 25.109 Accelerate-Stop Distance..........................................................80
Figure 11-1 Accelerate-Stop Time Delays...............................................80-7
Figure 11-2 Accelerate-Stop Speed Vs. Distance.....................................80-9
Figure 11-3 Anti-Skid System Response Characteristics
(On-Off System).................................................................80-13
Figure 11-4 Anti-Skid System Response Characteristics
(Quasi-Modulating System)................................................80-15
Figure 11-5 Anti-Skid System Response Characteristics
(Fully Modulating System).................................................80-17
Figure 11-6 Instantaneous Brake Force and Peak Brake Force..............80-21
Figure 11-7 Anti-Skid Efficiency-Wheel Slip Relationship...................80-23
Figure 11-8 Substantiation of the Optimal Slip Value...........................80-24
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12. FAR 25.111 Takeoff Path..............................................................................81
13. FAR 25.113 Takeoff Distance and Takeoff Run...........................................88
Figure 13-1 Takeoff Distance on a Dry Runway..........................................89
Figure 13-2 Takeoff Distance (All Engines Operating)...............................89
Figure 13-3 Takeoff Distance on a Wet Runway.........................................90
Figure 13-4 Takeoff Run (Critical Engine Fails at V )...............................91
EF
Figure 13-5 Takeoff Run (All Engines Operating).......................................91
Figure 13-6 Clearway Profiles......................................................................92
14. FAR 25.115 Takeoff Flight Path...................................................................92
Figure 14-1 Takeoff Segments & Nomenclature..........................................93
Figure 14-2 Net Takeoff Flight Path.............................................................94
15. FAR 25.117 Climb: General..94
16. FAR 25.119 Landing Climb: All-Engines Operating....................................95
17. FAR 25.121 Climb: One-Engine-Inoperative................................................96
18. FAR 25.123 En route Flight Paths.................................................................97
19. FAR 25.125 Landing.....................................................................................98
Figure 19-1 Landing Time Delays..............................................................103

Section 3. CONTROLLABILITY AND MANEUVERABILITY

20. FAR 25.143 General....................................................................................121
Figure 20-1 Sample Pitch Tracking Task...................................................129
Figure 20-2 A-PC Rating Criteria & Comparison to MIL Standard..........130
Figure 20-3 Example of Minimum Permitted HQ Rating for A-PC
Tendencies..............................................................................131
21. FAR 25.145 Longitudinal Control...............................................................135
22. FAR 25.147 Directional and Lateral Control..............................................140
23. FAR 25.149 Minimum Control Speed........................................................143

Section 4. TRIM

24. FAR 25.161 Trim [RESERVED]................................................................157

Section 5. STABILITY

25. FAR 25.171 General [RESERVED]............................................................171
26. FAR 25.173 Static Longitudinal Stability...................................................171
FAR 25.175 Demonstration of Static Longitudinal Stability......................171
Figure 26-1 Longitudinal Static Stability...................................................173
27. FAR 25.177 Static Directional and Lateral Stability...................................173
28. FAR 25.181 Dynamic Stability....................................................................175

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Section 6. STALLS

29. Stall Testing............................................................................189
FAR 25.201 Stall Demonstration................................................................189
FAR 25.203 Stall Characteristics................................................................194
FAR 25.207 Stall Warning..........................................................................197
Figure 29-1 Stall Test Time History...........................................................199
Figure 29-2 Stall C vs. Entry Rate.........................................................200
LCG
Figure 29-3 Stall C vs. Weight and Flap Setting......................................200
L
Figure 29-4 Stall Speeds vs. Weight and Flap Setting...............................201
Figure 29-5 Thrust Effect on Stall C .........................................................201
L

Section 7. GROUND AND WATER HANDLING CHARACTERISTICS

30. General....................................................................................211
FAR 25.231 Longitudinal Stability and Control.........................................211
FAR 25.233 Directional Stability and Control............................................211
FAR 25.235 Taxiing Condition [RESERVED]...........................................212
FAR 25.237 Wind Velocities......................................................................212
FAR 25.239 Spray Characteristics, Control, and Stability on Water..........213

Section 8. MISCELLANEOUS FLIGHT REQUIREMENTS

31. FAR 25.251 Vibration and Buffeting..........................................................221
Figure 31-1 Maneuvering Characteristics...................................................224
(Speeds up to the Lesser of V or M or Buffet Onset)
FC FC
Figure 31-2 Maneuvering Characteristics...................................................225
(Speeds between Figure 31-1 and V or M )
DF DF
32. FAR 25.253 High Speed Characteristics.....................................................225
33. FAR 25.255 Out-of-Trim Characteristics....................................................229
Figure 33-1 Mistrimmed Maneuvering Characteristics..............................231

CHAPTER 3. STRUCTURE

[RESERVED]

CHAPTER 4. DESIGN AND CONSTRUCTION

Section 1. GENERAL [RESERVED]

Section 2. CONTROL SURFACES [RESERVED]

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Section 3. CONTROL SYSTEMS

34. FAR 25.671 General....................................................................................261
[35-45] [RESERVED].........................................................................261
46. FAR 25.701 Flap and Slat Interconnections................................................261
47. FAR 25.703 Takeoff Warning System [RESERVED]................................262

Section 4. LANDING GEAR

[48-51] [RESERVED].........................................................................283
52. FAR 25.729 Retracting Mechanisms...........................................................283
53. FAR 25.731 Wheels ....................................................................................284
54. FAR 25.733 Tires [RESERVED]................................................................286
55. FAR 25.735 Brakes.....................................................................................286
56. FAR 25.737 Skis [RESERVED].................................................................301

Section 5. FLOATS AND HULLS

[57-59] [RESERVED].........................................................................311

Section 6. PERSONNEL AND CARGO ACCOMMODATIONS

[60-61] [RESERVED].........................................................................323
62. FAR 25.773 Pilot Compartment View........................................................323
[63-72] [RESERVED].........................................................................323

Section 7. EMERGENCY PROVISIONS

73. FAR 25.801 Ditching [RESERVED]..........................................................333
74. FAR 25.803 Emergency Evacuation............................................................333
[75-83] [RESERVED].........................................................................333

Section 8. VENTILATION AND HEATING

84. FAR 25.831 Ventilation...............................................................................343
85. FAR 25.832 Cabin Ozone Concentration [RESERVED]...........................343
86. FAR 25.833 Combustion Heating Systems [RESERVED].........................343

Section 9. PRESSURIZATION

87. FAR 25.841 Pressurized Cabins..................................................................353
88. FAR 25.843 Tests for Pressurized Cabins...................................................355

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Section 10. FIRE PROTECTION [RESERVED]

Section 11. MISCELLANEOUS [RESERVED]

CHAPTER 5. POWERPLANT

Section 1. GENERAL

89. FAR 25.901 Installation [RESERVED]......................................................387
90. FAR 25.903 Engines....................................................................................387
FAR 25.903(b) Engine Isolation......................................................................387
FAR 25.903(c) Control of Engine Rotation.....................................................387
FAR 25.903(d) Turbine Engine Installations...................................................388
FAR 25.903(e) Engine Restart Capability.......................................................389
91. FAR 25.904 Automatic Takeoff Thrust Control Systems (ATTCS)...........390
92. FAR 25.905 Propellers................................................................................392
93. FAR 25.907 Propeller Vibration [RESERVED].........................................392
94. FAR 25.925 Propeller Clearance [RESERVED].........................................392
95. FAR 25.929 Propeller Deicing....................................................................392
96. FAR 25.933 Reversing Systems..................................................................393
97. FAR 25.934 Turbojet Engine Thrust Reverser Sys. Tests [RESERVED]..396
98. FAR 25.937 Turbopropeller-Drag Limiting Systems..................................396
99. FAR 25.939 Turbine Engine Operating Characteristics..............................398
100. FAR 25.941 Inlet, Engine, and Exhaust Capability (RESERVED..............398
101. FAR 25.943 Negative Acceleration.............................................................399
102. FAR 25.945 Thrust or Power Augmentation System [RESERVED]..........399

Section 2. FUEL SYSTEM

[103-108] [RESERVED].........................................................................419
109. FAR 25.959 Unusable Fuel Supply.............................................................419
110. FAR 25.961 Fuel System Hot Weather Operation......................................421
[111-116] [RESERVED].........................................................................423
117. FAR 25.975 Fuel Tank Vents and Carburetor Vapor Vents........................423
[118-120] [RESERVED].........................................................................424

Section 3. FUEL SYSTEM COMPONENTS

[121-126] [RESERVED].........................................................................445
127. FAR 25.1001 Fuel Jettisoning System..........................................................445

Section 4. OIL SYSTEM [RESERVED]

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Section 5. COOLING

[128-130] [RESERVED].........................................................................481

Section 6. INDUCTION SYSTEM

131. FAR 25.1091 Air Induction...........................................................................497
132. FAR 25.1093 Induction System Icing Protection..........................................499
[133-136] [RESERVED].........................................................................501

Section 7. EXHAUST SYSTEM

137. FAR 25.1121 General....................................................................................511
[138-140] [RESERVED]

Section 8. POWERPLANT CONTROLS AND ACCESSORIES

[141-154] [RESERVED].........................................................................521

Section 9. POWERPLANT FIRE PROTECTION

[155-158] [RESERVED].........................................................................537
159. FAR 25.1187 Drainage and Ventilation of Fire Zones..................................537
[160-164] [RESERVED].........................................................................537
165. FAR 25.1197 Fire Extinguishing Agents......................................................537
[166-169] [RESERVED].........................................................................538

CHAPTER 6. EQUIPMENT

Section 1. GENERAL

170. FAR 25.1301 Function and Installation.........................................................559
171. FAR 25.1303 Flight and Navigation Instruments..........................................592
172. FAR 25.1305 Powerplant Instruments [RESERVED]..................................594
173. FAR 25.1307 Miscellaneous Equipment [RESERVED]..............................594
174. FAR 25.1309 Equipment, Systems, and Installations...................................594

Section 2. INSTRUMENTS: INSTALLATION

175. FAR 25.1321 Arrangement and Visibility [RESERVED]............................605
176. FAR 25.1322 Warning, Caution, and Advisory Lights [RESERVED].........605
177. FAR 25.1323 Airspeed Indicating System....................................................605
178. FAR 25.1325 Static Pressure Systems...........................................................608
179. FAR 25.1326 Pitot Heat Indicator Systems [RESERVED]..........................609
180. FAR 25.1327 Magnetic Direction Indicator [RESERVED]..........................609
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