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C ONTENTS
Chapter 1. DESIGN AND CONSTRUCTION
Section 1. CONTROL SYSTEMS
1. Section 25.671 General 1 a . Rule Text 1
2. Section 25.672 Stability augmentation and automatic and power-operated systems 2 a . Rule Text 2
3. Section 25.699 Lift and drag device indicator 3 a . Rule Text 3
b. Intent of Rule 3
c. Background 3
(1) Amendment 25-23 3
d. Policy/Compliance 3
(1) Advisory Circular (AC) 25-14 4 e . Reference 7
4. Section 25.701 Flap interconnection 7 a . Rule Text 7
5. Section 25.703 Takeoff warning system 8 a . Rule Text 8
b. Intent of Rule 8
c. Background 8
d. Policy/Compliance 9 e . Reference 9 [6-10] [ RESERVED] 9
Section 2. LANDING GEAR
11. Section 25.729 Retracting mechanism 11 a . Rule Text 11
b. Intent of Rule 12
c. Background 13
(1) Amendment 25-23 13
(2) Amendment 25-42 13
(3) Amendment 25-72 13 Paragraph Page No.
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(4) Amendment 25-75 13
d. Policy/Compliance 13
(1) Protection of equipment in wheel wells 13
(2) Landing gear position indication system 14
(3) Flap system/landing gear warning system tie-in 15
(4) Landing gear position indication system 15
(5) Landing gear slush tests 16 e . References 17 f . Definitions 17
12. Section 25.731 Wheels 17 a . Rule Text 17
b. Intent of Rule 17
c. Background 17
(1) Amendment 25-72 18 ( 2) Harmonization 18
d. Policy/Compliance 18 e . References 19
13. Section 25.733 Tires 19 a . Rule Text 20
b. Intent of Rule 21
c. Background 21
(1) Amendment 25-23 21
(2) Amendment 25-38 21
(3) Amendment 25-49 21
(4) Amendment 25-52 22
(5) Amendment 25-72 22
(6) Amendment 25-78 22
d. Policy/Compliance 22
(1) Approval of retreaded tires by similarity 22
(2) Approval: nonretreadable tires - qualification testing 24
(3) Approval method for substitute tires 25
(4) Replacement of bias ply tires with radial ply tires 26
(5) Certification of radial tire installation 28
(6) Critical conditions and maximum ramp weight definitions 30 e . References 31
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14. Section 25.735 Brakes 31 a . Rule Text 31
b. Intent of Rule 33
c. Background 34
(1) Amendment 25-23 34
(2) Amendment 25-48 34
(3) Amendment 25-52 34
(4) Amendment 25-72 34
(5) Amendment 25-92 34 ( 6) Harmonization 35
d. Policy/Compliance 35
(1) Carbon brake refurbishment (redensification) 35
(2) FAA/JAA certification requirements;
steel/carbon brakes 37
(3) Certification of replacement brakes 37
(4) Parking brake testing 40
(5) Worn brake requirements, non original equipment parts 41
(6) Determination of allowable worn brake limits 41
(7) Credit for reverse thrust in worn brake testing 46
(8) Certification of brake replacement components 47
(9) Ground equipment - brake cooling unit 51
(10) Certification of asbestos-free brake linings 52
(11) Certification of brake components - performance 53
(12) Approval of brake components utilizing new brake friction material 54
(13) Maximum quick turnaround times 55 e . References 57
Section 3. PERSONNEL AND CARGO ACCOMMODATIONS
15. Section 25.773 Pilot compartment view 59 a . Rule Text 59
b. Intent of Rule 60
c. Background 60
(1) Amendment 25-23 60
(2) Amendment 25-46 60
(3) Amendment 25-72 60 ( 4) Harmonization 60
d. Policy/Compliance 60 e . References 60 [16-25] [RESERVED] 60 Paragraph Page No.
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26. Section 25.783 Doors 61 a . Rule Text 61
b. Intent of Rule 62
c. Background 62
d. Policy/Compliance 62 e . Reference 62 [27-29] [RESERVED] 62
Section 4. VENTILATION AND HEATING
30. Section 25.831 Ventilation 63 a . Rule Text 63
b. Intent of Rule 64
c. Background 64
(1) Amendment 25-41 64
(2) Amendment 25-87 65 ( 3) Harmonization 65
(4) Amendment 25-89 65
d. Policy/Compliance 65
(1) Ventilation rates 65 ( 2) Smoke evacuation 65
(3) Ventilation system design 66
(4) Airplane operation with airconditioning packs off 66
(5) Fresh air and normal operating conditions 69
(6) Ventilation during takeoff 70 e . Reference 70
31. Section 25.832 Cabin ozone concentration 71 a . Rule Text 71
b. Intent of Rule 71
c. Background 71
(1) Amendment 25-56 71 ( 2) Operating Rule 72
d. Policy/Compliance 72
(1) Sea level equivalent 72
(2) Ground test 74
(3) Use of default retention ratio 74
(4) Use of operational limitations 75
(5) Meaning of "time-weighted average" 76
(6) Example of compliance with § 25.832 77 e . References 80
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32. Section 25.833 Combustion heating systems 80 VIII
a . Rule Text 80
b. Intent of Rule 80
c. Background 80
d. Policy/Compliance 80
(1) Standards for certification of combustion heaters 80 e . Reference 83
33. Section 25.841 Pressurized cabins 83 a . Rule Text 83
b. Intent of Rule 84
c. Background 84
(1) Amendment 25-38 84
(2) Amendment 25-87 84 ( 3) Harmonization 85
d. Policy/Compliance 85
(1) Rapid equalization of pressure 85
(2) Access to a pressurized cargo compartment in the engine burst zone during high altitude operation 85
(3) Cabin altitude limit; § 25.841(a) 86 e . References 87
34. Section 25.843 Tests for pressurized cabins 88 a . Rule Text 88
b. Intent of Rule 88
c. Background 88
(1) Amendment 25-87 88 ( 2) Harmonization 88
d. Policy/Compliance 89
(1) Pressure tests for compliance with § 25.843(a) 89 e . Reference 89
Section 5. FIRE PROTECTION
35. Section 25.851 Fire extinguishers 91 a . Rule Text 91
b. Intent of Rule 92
c. Background 92
d. Policy/Compliance 92 e . References 92
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36. Section 25.854 Lavatory fire protection 92 a . Rule Text 92
b. Intent of Rule 93
c. Background 93
d. Policy/Compliance 93
(1) Approval of lavatory smoke detectors 93
(2) Approval of lavatory fire extinguishers containing a gents other than Halon 95 e . References 95
37. Section 25.855 Cargo or baggage compartments 96 a . Rule Text 96
b. Intent of Rule 96
c. Background 97
(1) Amendment 25-15 97
(2) Amendment 25-32 97
(3) Amendment 25-60 97
(4) Amendment 25-72 97
(5) Amendment 25-93 97 ( 6) Harmonization 97
d. Policy/Compliance 97
(1) Halon concentration 98
(2) Class D to class C conversion 98
(3) Protection of critical equipment in class E cargo compartments 100
e. Reference 101
38. Section 25.857 Cargo compartment classification 101
a. Rule Text 101
b. Intent of Rule 102
c. Background 102
(1) Amendment 25-32 102
(2) Amendment 25-60 102
(3) Amendment 25-93 103
(4) Harmonization 103
d. Policy/Compliance 103
(1) Main deck cargo compartment fire protection certification procedures 103
(2) Class A cargo compartments 105
(3) Class E cargo compartments 106 X
(4) Access to Class E cargo compartments 107
(5) Freighter aircraft with accessible class E compartment 107
e. References 108
39. Section 25.858 Cargo or baggage compartment smoke or fire detection systems 108
a. Rule Text 108
b. Intent of Rule 108
c. Background 108
(1) Amendment 25-93 109
d. Policy/Compliance 109
(1) Smoke detection certification testing 109
(2) Certification testing for smoke detection 110
(3) Smoke detection certification testing 111
(4) William J. Hughes Technical Center Research and Developm ent 114
e. References 114
40. Section 25.863 Flammable fluid fire protection 114
a. Rule Text 114
b. Intent of Rule 115
c. Background 115
d. Policy/Compliance 115
e. Reference 115
41. Section 25.869 Fire protection systems 115
a. Rule Text 115
b. Intent of Rule 116
c. Background 116
(1) Amendment 25-72 116
d. Policy/Compliance 116
e. References 116
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Chapter 2. POWERPLANT
Section 1. GENERAL
42. Section 25.943 Negative acceleration 117
a. Rule Text 117
Section 2. FUEL SYSTEM COMPONENTS
43. Section 25.1001 Fuel jettisoning system 119
a. Rule Text 119
Section 3. POWERPLANT FIRE PROTECTION
44. Section 25.1183 Flammable fluid-carrying components 121
a. Rule Text 121
45. Section 25.1185 Flammable fluids 122
a. Rule Text 122
46. Section 25.1189 Shutoff means 122
a. Rule Text 122
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Chapter 3. EQUIPMENT
Section 1. GENERAL
47. Section 25.1301 Function and installation 125
a. Rule Text 125
b. Intent of Rule 125
c. Background 125
(1) Harmonization 125
d. Policy/Compliance 125
(1) JAR ACJ 25.1301(b) 126
e. Reference 126
48. Section 25.1309 Equipment, systems, and installations 126
a. Rule Text 126
b. Intent of Rule 127
c. Background 127
(1) Amendment 25-23 128
(2) Amendment 25-38 128
(3) Amendment 25-41 128
(4) Harmonization 128
d. Policy/Compliance 128
(1) Probability of a fire 128
(2) Examples 130
(3) Safe and reliable 130
e. References 130 [49-51] [RESERVED] 130
Section 2. INSTRUMENTS: INSTALLATION
52. Section 25.1325 Static pressure systems 131
a. Rule Text 131
b. Intent of Rule 132
c. Background 132
(1) Amendment 25-5 132
(2) Amendment 25-12 132
(3) Amendment 25-41 132
d. Policy/Compliance 132
e. Reference 132
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Section 3. SAFETY EQUIPMENT
53. Section 25 1419 Ice protection 133
a. Rule Text 133
b. Intent of Rule 133
c. Background 133
(1) Amendment 25-23 134
(2) Amendment 25-72 134
d. Policy/Compliance 134
e. References 134 [54-58] [RESERVED] 134
Section 4. MISCELLANEOUS EQUIPMENT
59. Section 25.1433 Vacuum systems 135
a. Rule Text 135
b. Intent of Rule 135
c. Background 135
(1) Amendment 25-72 135
d. Policy/Compliance 135
e. References 135
60. Section 25.1435 Hydraulic systems 135
a. Rule Text 135
b. Intent of Rule 136
c. Background 137
(1) Amendment 25-13 137
(2) Amendment 25-23 138
(3) Amendment 25-41 138
(4) Amendment 25-72 138
(5) Exemptions 138
(6) Harmonization 139
d. Policy/Compliance 139
(1) Hydraulic fluid contamination 139
(2) Certification of hydraulic lines for temporary repairs 140
(3) Use of hydraulic lines for temporary repairs 141
(4) Hydraulic system certification philosophy 142
(5) Interpretation of § 25.1435(a)(4) of 14 CFR 143
e. References 144
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61. Section 25.1438 Pressurization and pneumatic systems 145
a. Rule Text 145
b. Intent of Rule 145
c. Background 145
(1) Harmonization 145
d. Policy/Compliance 145
(1) Pneumatic versus pressurization system identification 145
e. References 146
62. Section 25.1439 Protective breathing equipment 146
a. Rule Text 146
b. Intent of Rule 147
c. Background 148
(1) Amendment 25-38 148
d. Policy/Compliance 148
(1) Protective breathing equipment usage when approved under TSO-C99 and TSO-C116 148
(2) Protective breathing equipment serviceability 149
(3) Protective breathing equipment on the flight deck 149
(4) Definition of terms used in § 25.1439 150
e. References 151
63. Section 25.1441 Oxygen equipment and supply 151
a. Rule Text 151
b. Intent of Rule 151
c. Background 151
d. Policy/Compliance 151
(1) Compliance with §§ 25.1309(c) and 25.1441(c) 151
(2) Guidance, availability of flightcrew oxygen 153
(3) Oxygen installation for medical use 155
e. Reference 156
64. Section 25.1443 Minimum mass flow of supplemental oxygen 156
a. Rule Text 156
b. Intent of Rule 157
c. Background 157
d. Policy/Compliance 157
e. Reference 157
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65. Section 25.1445 Equipment standards for the oxygen distributing system 158
a. Rule Text 158
b. Intent of Rule 158
c. Background 158
d. Policy/Compliance 158
e. Reference 158
66. Section 25.1447 Equipment standards for oxygen dispensing units 158
a. Rule Text 158
b. Intent of Rule 160
c. Background 160
(1) Amendment 25-41 160
(2) Amendment 25-87 160
d. Policy/Compliance 160
(1) Oxygen equipment for forward observer's position 160
e. References 161
67. Section 25.1449 Means for determining use of oxygen 161
a. Rule Text 161
b. Intent of Rule 161
c. Background 161
d. Policy/Compliance 162
(1) Oxygen equipment for observer's position 162
(2) Determination of passenger oxygen supply 163
e. References 163
68. Section 25.1450 Chemical oxygen generators 163
a. Rule Text 163
b. Intent of Rule 164
c. Background 164
d. Policy/Compliance 164
e. Reference 164
69. Section 25.1453 Protection of oxygen equipment from rupture 164
a. Rule Text 164
b. Intent of Rule 164
c. Background 164
d. Policy/Compliance 164
(1) Flexible plastic oxygen lines 165
(2) Use of plastic oxygen lines 165
e. Reference 166
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