14 CFR Part 27
252 sections · 4 appendices · 7 subparts · Amended 2026-09-15
AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT
5 Legal Interpretations 34 Special Conditions 19 ELOS findings View on eCFR ↗
Authority49 U.S.C. 106(f), 106(g), 40113, 44701-44702, 44704.
SourceDocket No. 5074, 29 FR 15695, Nov. 24, 1964, unless otherwise noted.
Subpart A— General 2 sections
Subpart B— Flight 27 sections
- § 27.21 Proof of compliance.
- § 27.25 Weight limits.
- § 27.27 Center of gravity limits.
- § 27.29 Empty weight and corresponding center of gravity.
- § 27.31 Removable ballast.
- § 27.33 Main rotor speed and pitch limits.
- § 27.45 General.
- § 27.49 Performance at minimum operating speed.
- § 27.51 Takeoff.
- § 27.65 Climb: all engines operating.
- § 27.67 Climb: one engine inoperative.
- § 27.71 Autorotation performance.
- § 27.75 Landing.
- § 27.87 Height-velocity envelope.
- § 27.141 General.
- § 27.143 Controllability and maneuverability.
- § 27.151 Flight controls.
- § 27.161 Trim control.
- § 27.171 Stability: general.
- § 27.173 Static longitudinal stability.
- § 27.175 Demonstration of static longitudinal stability.
- § 27.177 Static directional stability.
- § 27.231 General.
- § 27.235 Taxiing condition.
- § 27.239 Spray characteristics.
- § 27.241 Ground resonance.
- § 27.251 Vibration.
Subpart C— Strength Requirements 37 sections
- § 27.301 Loads.
- § 27.303 Factor of safety.
- § 27.305 Strength and deformation.
- § 27.307 Proof of structure.
- § 27.309 Design limitations.
- § 27.321 General.
- § 27.337 Limit maneuvering load factor.
- § 27.339 Resultant limit maneuvering loads.
- § 27.341 Gust loads.
- § 27.351 Yawing conditions.
- § 27.361 Engine torque.
- § 27.391 General.
- § 27.395 Control system.
- § 27.397 Limit pilot forces and torques.
- § 27.399 Dual control system.
- § 27.411 Ground clearance: tail rotor guard.
- § 27.427 Unsymmetrical loads.
- § 27.471 General.
- § 27.473 Ground loading conditions and assumptions.
- § 27.475 Tires and shock absorbers.
- § 27.477 Landing gear arrangement.
- § 27.479 Level landing conditions.
- § 27.481 Tail-down landing conditions.
- § 27.483 One-wheel landing conditions.
- § 27.485 Lateral drift landing conditions.
- § 27.493 Braked roll conditions.
- § 27.497 Ground loading conditions: landing gear with tail wheels.
- § 27.501 Ground loading conditions: landing gear with skids.
- § 27.505 Ski landing conditions.
- § 27.521 Float landing conditions.
- § 27.547 Main rotor structure.
- § 27.549 Fuselage, landing gear, and rotor pylon structures.
- § 27.561 General.
- § 27.562 Emergency landing dynamic conditions.
- § 27.563 Structural ditching provisions.
- § 27.571 Fatigue evaluation of flight structure.
- § 27.573 Damage Tolerance and Fatigue Evaluation of Composite Rotorcraft Structures.
Subpart D— Design and Construction 62 sections
- § 27.601 Design.
- § 27.602 Critical parts.
- § 27.603 Materials.
- § 27.605 Fabrication methods.
- § 27.607 Fasteners.
- § 27.609 Protection of structure.
- § 27.610 Lightning and static electricity protection.
- § 27.611 Inspection provisions.
- § 27.613 Material strength properties and design values.
- § 27.619 Special factors.
- § 27.621 Casting factors.
- § 27.623 Bearing factors.
- § 27.625 Fitting factors.
- § 27.629 Flutter.
- § 27.653 Pressure venting and drainage of rotor blades.
- § 27.659 Mass balance.
- § 27.661 Rotor blade clearance.
- § 27.663 Ground resonance prevention means.
- § 27.671 General.
- § 27.672 Stability augmentation, automatic, and power-operated systems.
- § 27.673 Primary flight control.
- § 27.674 Interconnected controls.
- § 27.675 Stops.
- § 27.679 Control system locks.
- § 27.681 Limit load static tests.
- § 27.683 Operation tests.
- § 27.685 Control system details.
- § 27.687 Spring devices.
- § 27.691 Autorotation control mechanism.
- § 27.695 Power boost and power-operated control system.
- § 27.723 Shock absorption tests.
- § 27.725 Limit drop test.
- § 27.727 Reserve energy absorption drop test.
- § 27.729 Retracting mechanism.
- § 27.731 Wheels.
- § 27.733 Tires.
- § 27.735 Brakes.
- § 27.737 Skis.
- § 27.751 Main float buoyancy.
- § 27.753 Main float design.
- § 27.755 Hulls.
- § 27.771 Pilot compartment.
- § 27.773 Pilot compartment view.
- § 27.775 Windshields and windows.
- § 27.777 Cockpit controls.
- § 27.779 Motion and effect of cockpit controls.
- § 27.783 Doors.
- § 27.785 Seats, berths, litters, safety belts, and harnesses.
- § 27.787 Cargo and baggage compartments.
- § 27.801 Ditching.
- § 27.805 Flight crew emergency exits.
- § 27.807 Emergency exits.
- § 27.831 Ventilation.
- § 27.833 Heaters.
- § 27.853 Compartment interiors.
- § 27.855 Cargo and baggage compartments.
- § 27.859 Heating systems.
- § 27.861 Fire protection of structure, controls, and other parts.
- § 27.863 Flammable fluid fire protection.
- § 27.865 External loads.
- § 27.871 Leveling marks.
- § 27.873 Ballast provisions.
Subpart E— Powerplant 58 sections
- § 27.901 Installation.
- § 27.903 Engines.
- § 27.907 Engine vibration.
- § 27.917 Design.
- § 27.921 Rotor brake.
- § 27.923 Rotor drive system and control mechanism tests.
- § 27.927 Additional tests.
- § 27.931 Shafting critical speed.
- § 27.935 Shafting joints.
- § 27.939 Turbine engine operating characteristics.
- § 27.951 General.
- § 27.952 Fuel system crash resistance.
- § 27.953 Fuel system independence.
- § 27.954 Fuel system lightning protection.
- § 27.955 Fuel flow.
- § 27.959 Unusable fuel supply.
- § 27.961 Fuel system hot weather operation.
- § 27.963 Fuel tanks: general.
- § 27.965 Fuel tank tests.
- § 27.967 Fuel tank installation.
- § 27.969 Fuel tank expansion space.
- § 27.971 Fuel tank sump.
- § 27.973 Fuel tank filler connection.
- § 27.975 Fuel tank vents.
- § 27.977 Fuel tank outlet.
- § 27.991 Fuel pumps.
- § 27.993 Fuel system lines and fittings.
- § 27.995 Fuel valves.
- § 27.997 Fuel strainer or filter.
- § 27.999 Fuel system drains.
- § 27.1011 Engines: General.
- § 27.1013 Oil tanks.
- § 27.1015 Oil tank tests.
- § 27.1017 Oil lines and fittings.
- § 27.1019 Oil strainer or filter.
- § 27.1021 Oil system drains.
- § 27.1027 Transmissions and gearboxes: General.
- § 27.1041 General.
- § 27.1043 Cooling tests.
- § 27.1045 Cooling test procedures.
- § 27.1091 Air induction.
- § 27.1093 Induction system icing protection.
- § 27.1121 General.
- § 27.1123 Exhaust piping.
- § 27.1141 Powerplant controls: general.
- § 27.1143 Engine controls.
- § 27.1145 Ignition switches.
- § 27.1147 Mixture controls.
- § 27.1151 Rotor brake controls.
- § 27.1163 Powerplant accessories.
- § 27.1183 Lines, fittings, and components.
- § 27.1185 Flammable fluids.
- § 27.1187 Ventilation and drainage.
- § 27.1189 Shutoff means.
- § 27.1191 Firewalls.
- § 27.1193 Cowling and engine compartment covering.
- § 27.1194 Other surfaces.
- § 27.1195 Fire detector systems.
Subpart F— Equipment 39 sections
- § 27.1301 Function and installation.
- § 27.1303 Flight and navigation instruments.
- § 27.1305 Powerplant instruments.
- § 27.1307 Miscellaneous equipment.
- § 27.1309 Equipment, systems, and installations.
- § 27.1316 Electrical and electronic system lightning protection.
- § 27.1317 High-intensity Radiated Fields (HIRF) Protection.
- § 27.1321 Arrangement and visibility.
- § 27.1322 Warning, caution, and advisory lights.
- § 27.1323 Airspeed indicating system.
- § 27.1325 Static pressure systems.
- § 27.1327 Magnetic direction indicator.
- § 27.1329 Automatic pilot and flight guidance system.
- § 27.1337 Powerplant instruments.
- § 27.1351 General.
- § 27.1353 Energy storage systems.
- § 27.1357 Circuit protective devices.
- § 27.1361 Master switch.
- § 27.1365 Electric cables.
- § 27.1367 Switches.
- § 27.1381 Instrument lights.
- § 27.1383 Landing lights.
- § 27.1385 Position light system installation.
- § 27.1387 Position light system dihedral angles.
- § 27.1389 Position light distribution and intensities.
- § 27.1391 Minimum intensities in the horizontal plane of forward and rear position lights.
- § 27.1393 Minimum intensities in any vertical plane of forward and rear position lights.
- § 27.1395 Maximum intensities in overlapping beams of forward and rear position lights.
- § 27.1397 Color specifications.
- § 27.1399 Riding light.
- § 27.1401 Anticollision light system.
- § 27.1411 General.
- § 27.1413 Safety belts.
- § 27.1415 Ditching equipment.
- § 27.1419 Ice protection.
- § 27.1435 Hydraulic systems.
- § 27.1457 Cockpit voice recorders.
- § 27.1459 Flight data recorders.
- § 27.1461 Equipment containing high energy rotors.
Subpart G— Operating Limitations and Information 27 sections
- § 27.1501 General.
- § 27.1503 Airspeed limitations: general.
- § 27.1505 Never-exceed speed.
- § 27.1509 Rotor speed.
- § 27.1519 Weight and center of gravity.
- § 27.1521 Powerplant limitations.
- § 27.1523 Minimum flight crew.
- § 27.1525 Kinds of operations.
- § 27.1527 Maximum operating altitude.
- § 27.1529 Instructions for Continued Airworthiness.
- § 27.1541 General.
- § 27.1543 Instrument markings: general.
- § 27.1545 Airspeed indicator.
- § 27.1547 Magnetic direction indicator.
- § 27.1549 Powerplant instruments.
- § 27.1551 Oil quantity indicator.
- § 27.1553 Fuel quantity indicator.
- § 27.1555 Control markings.
- § 27.1557 Miscellaneous markings and placards.
- § 27.1559 Limitations placard.
- § 27.1561 Safety equipment.
- § 27.1565 Tail rotor.
- § 27.1581 General.
- § 27.1583 Operating limitations.
- § 27.1585 Operating procedures.
- § 27.1587 Performance information.
- § 27.1589 Loading information.
Related Advisory Circulars 102 current · 108 cancelled
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- AC 20-154AGuide for Developing a Receiving Inspection System for Aircraft Parts and MaterialsCurrent2024-07-03↗
- AC 20-158BThe Certification of Aircraft Electrical and Electronic Systems for Operation in the High-Intensity Radiated Fields (HIRF) EnvironmentCurrent2024-05-20↗
- AC 20-186AAirworthiness and Operational Approval of Cockpit Voice Recorder SystemsCurrent2024-05-06↗
- AC 20-29CApproval and Use of Fuel System Icing Inhibitors (FSII)Current2024-03-27↗
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- AC 20-165BAirworthiness Approval of Automatic Dependent Surveillance - Broadcast OUT SystemsCurrent2015-12-07↗
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- AC 20-172BAirworthiness Approval for ADS-B In Systems and ApplicationsCurrent2015-05-20↗
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- AC 20-24DApproval of Propulsion Fuels, Additives, and Lubricating OilsCurrent2014-06-30↗
- AC 20-176AService Bulletins Related to Airworthiness Directives and Indicating FAA Approval on Service DocumentsCurrent2014-06-16↗
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- AC 20-179Certification Data Retention Agreements and Government RecordsCurrent2013-06-10↗
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- AC 20-175Controls for Flight Deck SystemsCurrent2011-12-08↗
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- AC 20-136BAircraft Electrical and Electronic System Lightning ProtectionCurrent2011-09-07↗
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