AC 25-7B

Historical

Advisory circular · Flight Test Guide for Certification of Transport Category Airplanes

A newer version is currentThis is a historical version. AC 25-7D CHG 1 is the version in force, approved September 16, 2025.
Approved
December 7, 2011
Last reviewed
June 8, 2015
This change
Change 1 Incorporated
Cancels
AC25-7A
Cancelled by
AC25-7C
Family
AC 25-7 · 6 versions
Revision
B
14 CFR parts
25

Guidance, not mandatory unless a rule or AD requires it. DRS record last changed November 21, 2025.

Show pages 1–4

Change 1 iv

Table of Contents (continued)

Paragraph Page No.

62. Pilot Compartment View - § 25.773._____________________________________ 173

63. - 72. [Reserved]_____________________________________________________ 173 Section 7. Emergency Provisions____________________________________________ 173

73. Ditching - § 25.801 [Reserved]_________________________________________ 173

74. Emergency Egress Assist Means and Escape Routes - § 25.810. _______________ 173

75. - 83. [Reserved]_____________________________________________________ 173 Section 8. Ventilation and Heating__________________________________________ 173

84. Ventilation - § 25.831 ________________________________________________ 173

85. Cabin Ozone Concentration - § 25.832 [Reserved] _________________________ 174

86. Combustion Heating Systems - § 25.833 [Reserved] ________________________ 174 Section 9. Pressurization __________________________________________________ 174

87. Pressurized Cabins - § 25.841.__________________________________________ 174

88. Tests For Pressurized Cabins - § 25.843 __________________________________ 177 Section 10. Fire Protection [Reserved] ______________________________________ 178 Section 11. Miscellaneous [Reserved] _______________________________________ 178 Chapter 5 - Powerplant ______________________________________________________ 179 Section 1. General _______________________________________________________ 179

89. Installation - § 25.901. [Reserved] ______________________________________ 179

90. Engines - § 25.903. __________________________________________________ 179

91. Automatic Takeoff Thrust Control System (ATTCS) - § 25.904._______________ 182

92. Propellers - § 25.905._________________________________________________ 184

93. Propeller Vibration and Fatigue - 25.907 [Reserved] _______________________ 184

94. Propeller Clearance - § 25.925 [Reserved]________________________________ 184

95. Propeller Deicing - § 25.929.___________________________________________ 185

96. Reversing Systems - § 25.933.__________________________________________ 185

Change 1 v

Table of Contents (continued)

Paragraph Page No.

97. Turbojet Engine Thrust Reverser System Tests - § 25.934. [Reserved] __________ 188

98. Turbopropeller-Drag Limiting Systems - § 25.937 __________________________ 188

99. Turbine Engine Operating Characteristics - § 25.939 ________________________ 190

100. Inlet, Engine, and Exhaust Compatibility - § 25.941. [Reserved] _____________ 190

101. Negative Acceleration - § 25.943. ____________________________________ 190

102. Thrust or Power Augmentation System § 25.945. [Reserved] ______________ 191 Section 2. Fuel System ____________________________________________________ 191 [103. - 108.] [Reserved]_________________________________________________ 191

109. Unusable Fuel Supply - § 25.959. ____________________________________ 191

110. Fuel System Hot Weather Operation - § 25.961._________________________ 193 [111. - 116.] [Reserved]_________________________________________________ 195

117. Fuel Tank Vents and Carburetor Vapor Vents - § 25.975. _________________ 195 [118. - 120.] [Reserved]_________________________________________________ 197 Section 3. Fuel System Components_________________________________________ 197 [121. - 126.] [Reserved]_________________________________________________ 197

127. Fuel Jettisoning System- § 25.1001. __________________________________ 197 Section 4. Oil System [Reserved] ___________________________________________ 200 Section 5. Cooling________________________________________________________ 200 [128. - 130.] [Reserved]_________________________________________________ 200 Section 6. Induction System _______________________________________________ 200

131. Air Induction - § 25.1091 __________________________________________ 200

132. Induction System Icing Protection - § 25.1093. _________________________ 202 [133. - 136.] [Reserved]_________________________________________________ 204 Section 7. Exhaust System_________________________________________________ 204

Change 1 vi

Table of Contents (continued)

Paragraph Page No.

137. General - § 25.1121. ______________________________________________ 204 [138. - 140.] [Reserved]_________________________________________________ 205 Section 8. Powerplant Controls and Accessories ______________________________ 205 [141. - 154.] [Reserved]_________________________________________________ 205 Section 9. Powerplant Fire Protection _______________________________________ 205 [155. - 158.] [Reserved]_________________________________________________ 205

159. Drainage and Ventilation Of Fire Zones - § 25.1187. _____________________ 205 [160. - 164.] [Reserved]_________________________________________________ 206

165. Fire Extinguishing Agents - § 25.1197.________________________________ 206 [166. - 169.] [Reserved]_________________________________________________ 206 Chapter 6 - Equipment_______________________________________________________ 207 Section 1. General _______________________________________________________ 207

170. Equipment – Function and Installation - § 25.1301. ______________________ 207

171. Flight and Navigation Instruments - § 25.1303. ___________________________ 240

172. Powerplant Instruments - § 25.1305. [Reserved] ________________________ 241

173. Miscellaneous Equipment - § 25.1307. [Reserved] ______________________ 241

174. Equipment, Systems, and Installations - § 25.1309. ______________________ 242 Section 2. Instruments: Installation ________________________________________ 242

175. Arrangement and Visibility - § 25.1321. [Reserved] _____________________ 242

176. Warning, Caution, and Advisory Lights - § 25.1322. [Reserved] ___________ 242

177. Airspeed Indicating System - § 25.1323 _______________________________ 242

178. Static Pressure Systems - § 25.1325(d) and (e) __________________________ 246

179. Pitot Heat Indication Systems - § 25.1326. [Reserved] ___________________ 247

180. Magnetic Direction Indicator - § 25.1327. [Reserved]____________________ 247

Change 1 vii Table of Contents (continued)

Paragraph Page No.

181. Automatic Pilot System - § 25.1329 __________________________________ 247 [182. - 185.] [Reserved]_________________________________________________ 263 Section 3. Electrical Systems and Equipment _________________________________ 264

186. General - § 25.1351. ______________________________________________ 264

187. Electrical Equipment and Installations - § 25.1353_______________________ 266

188. Distribution System - § 25.1355 _____________________________________ 268

189. Circuit Protective Devices - § 25.1357. [Reserved] ______________________ 268

190. Electrical System Tests - § 25.1363. __________________________________ 268 Section 4. Lights _________________________________________________________ 268

191. Instrument Lights - § 25.1381._______________________________________ 268

192. Landing Lights - § 25.1383._________________________________________ 269

193. Position Light System Installation - § 25.1385 __________________________ 269 [194. - 200.] [Reserved]_________________________________________________ 269

201. Anti-Collision Light System - § 25.1401_______________________________ 269

202. Wing Icing Detection Lights - § 25.1403. ______________________________ 270 Section 5. Safety Equipment _______________________________________________ 270 [203. - 207.] [Reserved _________________________________________________ 270 Section 6. Miscellaneous Equipment ________________________________________ 270

208. Electronic Equipment - § 25.1431 ____________________________________ 270 [209. - 223.] [Reserved]__________________________________________________ 270 Chapter 7 – Operating Limitations and Information. ______________________________ 271 Section 1. General [Reserved]______________________________________________ 271 Section 2. Operating Limitations [Reserved] _________________________________ 271 Section 3. Markings and Placards [Reserved]_________________________________ 271

Change 1 viii Table of Contents (continued)

Paragraph Page No.

Section 4. Airplane Flight Manual __________________________________________ 271

224. General - § 25.1581 _______________________________________________ 271 [225. - 227.] [Reserved]_________________________________________________ 271 Chapter 8 - Airworthiness: Miscellaneous Items _________________________________ 272

228. Design and Function of Artificial Stall Warning and Identification Systems. __ 272

229. Reduced and Derated Thrust Takeoff Operations ________________________ 275

230. Runway Gradients Greater Than ± 2 Percent. ___________________________ 276

231. Criteria For Approval of Steep Approach To Landing.____________________ 277

232. Takeoff and Landing On Unpaved Runways. ___________________________ 281

233. Accountability of Performance Degradation Relative to Both Minor Design Changes (External Posture) and Configuration Deviation List (CDL) Items. _______ 284

234. Configuration Deviation List. _______________________________________ 285

235. Spare Engine Pod. ________________________________________________ 287

236. Authorization For Ferry Flight With One Engine Inoperative - § 91.611. _____ 287

237. Instrument Landing System Weather Minima. __________________________ 288

238. Takeoff Performance Credit For Alternate Forward Center of Gravity Limits. _ 289

239. Performance Credit For Automatic Propeller Drag Reduction Devices._______ 292

240. Airplane Backing Using Reverse Thrust. ______________________________ 293

Change 1 ix

Table of Contents (continued)

Figures

Figure Page No.

Figure 3-1. Weight Tolerance Limits_____________________________________________ 6 Figure 3-2. Equivalent Weight Extrapolation ______________________________________ 7 Figure 3-3. Test Parameters That Normally Can Be Corrected ________________________ 9 Figure 3-4. Wind Profile Variation _____________________________________________ 10 Figure 11-1. Accelerate-Stop Time Delays _______________________________________ 35 Figure 11-2. Accelerate-Stop Speed vs. Distance __________________________________ 37 Figure 11-3. Anti-Skid System Response Characteristics____________________________ 41 Figure 11-4. Anti-Skid System Response Characteristics____________________________ 42 Figure 11-5. Anti-Skid System Response Characteristics____________________________ 44 Figure 11-6. Instantaneous Brake Force and Peak Brake Force _____________________ 47 Figure 11-7. Anti-Skid Efficiency – Wheel Slip Relationship ________________________ 49 Figure 11-8. Substantiation of the Optimal Slip Value______________________________ 51 Figure 13-1. Takeoff Distance on a Dry Runway __________________________________ 63 Figure 13-2. Takeoff Distance _________________________________________________ 64 Figure 13-3. Takeoff Distance On a Wet Runway _________________________________ 65 Figure 13-4. Takeoff Run_____________________________________________________ 65 Figure 13-5. Takeoff Run_____________________________________________________ 66 Figure 13-6. Clearway Profiles ________________________________________________ 67 Figure 14-1. Takeoff Segments & Nomenclature __________________________________ 68

Change 1 x

Table of Contents (continued)

Figure Page No.

Figure 14-2. Net Takeoff Flight Path ___________________________________________ 69 Figure 19-1. Landing Time Delays _____________________________________________ 78 Figure 20-1. Sample Pitch Tracking Task________________________________________ 89 Figure 20-2. A-PC Rating Criteria and Comparison To Mil Standard _________________ 90 Figure 20-3 Example of Acceptable HQ Rating For A-PC Tendencies_________________ 91 Figure 26-1. Longitudinal Static Stability _______________________________________ 111 Figure 29-1. Thrust Effect On Stall Speed ______________________________________ 123 Figure 29-2. CLMAX and Load Factor___________________________________________ 124 Figure 29-3. CLMAX vs Entry Rate _____________________________________________ 126 Figure 29-4. CLMAX vs Weight and Flap Setting __________________________________ 126 Figure 29-5. Stall Speed vs Weight and Flap Setting ______________________________ 128 Figure 31-1. Maneuvering Characteristics ______________________________________ 142 Figure 31-2. Maneuvering Characteristics ______________________________________ 142 Figure 33-1. Mistrimmed Maneuvering Characteristics____________________________ 150 Figure 181-1 Altitude Loss versus Altitude Go-Around Mode _______________________ 255

Change 1 xi

Table of Contents (continued)

Appendices Appendix Page No.

Appendix 1 _______________________________________________________________ A1-1 Acronyms and Abbreviations _____________________________________________ A1-1 Appendix 2 _______________________________________________________________ A2-1 Function and Reliability Tests - § 21.35(b)(2) ________________________________ A2-1 Appendix 3 _______________________________________________________________ A3-1 Correction of Air Minimum Control Speed To Standard Conditions_____________ A3-1

1. Theoretical Basis___________________________________________________ A3-1

2. Constant C n Method ________________________________________________ A3-2

3. Graphical Method __________________________________________________ A3-3

4. Equation Method___________________________________________________ A3-7 Appendix 4 _______________________________________________________________ A4-1 History of Jet Transport Performance Standards_____________________________ A4-1 Special Civil Air Regulation No. SR-422 ____________________________________ A4-2 Performance __________________________________________________________ A4-5 Airplane Flight Manual_________________________________________________ A4-14 Operating Rules ______________________________________________________ A4-14 Special Civil Air Regulation No. SR-422A __________________________________ A4-17 Performance _________________________________________________________ A4-25 Airplane Flight Manual_________________________________________________ A4-35 Operating Rules ______________________________________________________ A4-36 Special Civil Air Regulation No. SR-422B __________________________________ A4-40 Performance _________________________________________________________ A4-43 Airplane Flight Manual_________________________________________________ A4-54

Change 1 xii

Table of Contents (continued)

Appendices

Appendix Page No.

Operating Rules ______________________________________________________ A4-55 Appendix 5 _______________________________________________________________ A5-1 Historical Development Of Accelerate-Stop Time Delays ______________________ A5-1 Figure 1. Accelerate-Stop Time Delays___________________________________ A5-2 Figure 2. Accelerate-Stop Time Delays___________________________________ A5-4 Appendix 6 _______________________________________________________________ A6-1 FAA Handling Qualities Rating Method ____________________________________ A6-1 Figure 1. Airworthiness HQ Regulations Impacted/Outpaced by Technology _____ A6-2 Figure 2. Probability vs. Consequence Graph ______________________________ A6-3 Figure 3. Development of FAA HQRM Criteria____________________________ A6-4 Figure 4. Major Elements of Task-Oriented Handling Qualities Rating Method ___ A6-4 Figure 5. Probability Guidelines for Combined Occurrence Flight Conditions ____ A6-5 Figure 6. Flaps UP Flight Envelopes _____________________________________ A6-7 Figure 7. Flaps DOWN Flight Envelopes _________________________________ A6-8 Figure 8. Pilot Ratings ________________________________________________ A6-9 Figure 9. Probability Combination Leading to HQ Rating ___________________ A6-10 Figure 10. Probability Guidelines to Determine HQ Requirements ____________ A6-11 Figure 11. General HQ Task Categories _________________________________ A6-12 Figure 12. Minimum HQ Requirements _________________________________ A6-13 Appendix 7 _______________________________________________________________ A7-1 Rudder Pedal Force-Limited Air Minimum Control Speed_____________________ A7-1

Change 1

1 Introduction

1. Purpose.

a. This Advisory Circular (AC ) provides upda ted guidance for the flight test evaluation of transport category airplanes. These guidelines provide an acceptable means of demonstrating compliance with the pertinent regulations of Title 14, Code of Federal Regulations (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 This AC is not mandatory and does not constitute a regulation. It describes acceptable means, but not the only means, for demonstrating compliance with the applicable regulation(s). The FAA will consider other methods of demonstrating compliance that an applicant may elect to present. If we become aware of circumstances that convince us that following this AC would not result in compliance with the applicable regulations, we will not be bound by the terms of this AC, and we may require additional substantiation or design changes as a basis for finding compliance.

This material does not change, create any additional, authorize changes in, or permit deviations from existing regulatory requirements.

b. See Appendix 1 for a list of acronyms and abbreviations used in this AC.

2. Applicability. These methods and procedures are provided in the interest of certification approval for use during all transport category airplane flight test certification activities. This material is not to be construed as regulatory or having a mandatory effect. The procedures set forth herein are one acceptable means of compliance with applicable sections of part 25. Any alternative 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 complying with the requirements 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.

3. Cancellation. AC-25-7B, “Flight Test Guide for Certification of Transport Category Airplanes, “dated March 29, 2011, is cancelled.

4. 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 address airplane performance and handling characteristics. AC 25-7 has been revised three times to reflect changes in the part 25 regulatory requirements, changes in guidance and policy, and advances in technology. The first revision, AC 25-7A, updated the original AC to incorporate the policy and guidance material applicable to all sections of part 25, not just subpart B. The material related to regulations outside of subpart B superseded that contained in Order 8110.8, which was cancelled when AC 25-7A was issued.

Change 1 to AC 25-7A added acceptable means of compliance for the regulatory changes

Change 1 2 associated with amendments 92 and 98 to part 25. AC 25-7B added acceptable means of compliance for the regulatory changes associated with amendments 108, 109, and 115 to part 25, and revised guidance for expanding takeoff and landing data for airport elevations higher than those at which flight testing was conducted. Means of compliance associated with flight in icing conditions is removed as this material is now contained in AC 25-25. AC 25-7B Change 1 provides updated guidance material to ensure consistent application of airworthiness requirements adopted by Amendment 25-135 to 14 CFR part 25.

5. Related Publications. Certification personnel should be familiar with FAA Order 8110.4c, “Type Certification,” and FAA Order 8100.5A, “Aircraft Certification Service Mission, Responsibilities, Relationships, and Programs.” In this AC, reference is made to other FAA advisory circulars that provide guidance on various aspects of type certification and supplemental type certification.

3 Chapter 1 - General

1. Applicability - § 25.1 [Reserved]

2. Special Retroactive Requirements - § 25.2 [Reserved]