This specification covers the manufacture of gyroplanes and includes design and performance requirements for light sport gyroplane aircraft. A gyroplane is a rotorcraft to be used for day visual flight rules (VFR) only, with rotor blades that are not engine-driven in flight and are supported in flight by the reaction of the air on a single rotor that rotates freely on a substantially vertical axis when the aircraft is in horizontal flight. Aircraft having the following basic features will be so regarded: rotors of either fixed collective pitch or collective pitch control that are not adjustable in flight, single engine with fixed or ground adjustable pitch propeller, no more than two occupant seats, and a maximum gross weight of some value. For compliance, the following flight requirements should be met: load distribution limit, weight limit, empty weight, removable ballast, and rotor speed limit. In order to comply in terms of performance, the requirements for the following shall be evaluated: takeoff, climb, glide, never exceed airspeed, minimum controllable airspeed for level flight, best rate of climb airspeed, landing distance, maximum operating altitude, and height/velocity envelope. The gyroplane must be safely controllable and maneuverable with sufficient margin of control movement and blade freedom to correct for atmospheric turbulence and permit control of the attitude of the gyroplane at all power settings at the critical weight and balance at sea level and at the maximum operating altitude. The evaluation of the gyroplane's longitudinal lateral and directional control and stability shall be discussed. In terms of structure requirements, the following should be taken into consideration: flight loads, engine torque, control system loads, stabilizing and control surfaces, ground loads, main component requirements, emergency landing conditions, and other loads.

1.1 This specification covers the manufacture of gyroplanes. This specification includes design and performance requirements for light sport gyroplane aircraft.

1.2 This specification applies to light gyroplane aircraft seeking civil aviation authority approval in the form of flight certificates, flight permits, or other like documentation.

1.3 A gyroplane for the purposes of this specification is defined as a rotorcraft to be used for day VFR only, with rotor blades that are not engine-driven in flight and are supported in flight by the reaction of the air on a single rotor that rotates freely on a substantially vertical axis when the aircraft is in horizontal flight.

1.4 These requirements apply to light gyroplanes of orthodox design. Aircraft having the following basic features will be so regarded:

1.4.1 Rotors of either fixed collective pitch or collective pitch control that are not adjustable in flight,

1.4.2 Single engine with fixed or ground adjustable pitch propeller,

1.4.3 No more than two occupant seats, and

1.4.4 A maximum gross weight (MGW) of 725 kg (1600 lb) or less.

1.5 Where it can be shown that a particular feature is similar in all significant respects to a feature that has historically demonstrated compliance with this specification and can be considered a separate entity in terms of its operation, that feature shall be deemed to be applicable and in compliance with this specification.

1.6 Where these requirements are inappropriate to particular design and construction features, it will be necessary to submit an appropriate amendment of this specification to ASTM Committee F37 on Light Sport Aircraft for consideration and approval.

1.7 The values stated in SI units are to be regarded as standard. The values given in parentheses are for information only.

1.8 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.9 Table of Contents: 

Section

Scope

1

Table of Contents

1.9

Referenced Documents

2

Terminology

3

 Definitions

3.1

 Acronyms

3.2

Flight

4

 General

4.1

 Performance

4.2

 Controllability and Maneuverability

4.3

 Longitudinal Lateral and Directional Control

4.4

 Stability

4.5

 Ground-Handling Characteristics

4.6

 Miscellaneous Flight Requirements

4.7

Structure

5

 General

5.1

 Flight Loads

5.2

 Engine Torque

5.3

 Control System Loads

5.4

 Stabilizing and Control Surfaces

5.5

 Ground Loads

5.6

 Main Component Requirements

5.7

 Emergency Landing Conditions

5.8

 Other Loads

5.9

Design and Construction

6

 General

6.1

 Materials

6.2

 Fabrication Methods

6.3

 Locking of Connections

6.4

 Protection of Structure

6.5

 Inspection

6.6

 Provisions for Rigging and Derigging

6.7

 Material Strength Properties and Design Values

6.8

 Fatigue Strength

6.9

 Special Factors of Safety

6.10

 Bearing Factors

6.10.2

 Fitting Factors

6.10.3

 Cable Factor

6.10.4

 Rotor Components Factor

6.10.5

 Flutter Prevention and Structural Stiffness

6.11

 Control Surfaces and Rotors

6.12

 Control Surface Installations (Other Than Rotor Blades)

6.13

 Control Surface Hinges (Other Than Rotor Blades)

6.14

 Rotor Mass Balance

6.15

 Rotor Blade Clearance

6.16

 Rotor Head Bearings

6.17

 Control Systems

6.18

 Cockpit Design

6.19

Powerplant

7

 General

7.1

 Engine

7.2

 Engine and Propeller Compatibility

7.3

 Rotor Spin-Up and Brake Systems

7.4

 Powerplant and Rotor System Compatibility

7.5

 Propeller Clearance

7.6

 Fuel System

7.7

 Oil System

7.8

 Cooling

7.9

 Induction System

7.10

 Exhaust System

7.11

 Powerplant Controls and Accessories

7.12

 Cowling and Nacelle

7.13

Equipment

8

 General

8.1

 Instruments—Installation

8.2

 Electrical Systems and Equipment

8.3

 Miscellaneous Equipment

8.4

Operating Limitations and Information

9

 General

9.1

 Airspeed Limitations

9.2

 Weight and Balance

9.3

 Powerplant and Propeller Limitations

9.4

 Pilot Operating Handbook, POH

9.5

 Maintenance Manual

9.6

 Markings and Placards

9.7

Propellers

10

 Design and Construction

10.1

Keywords

12

1.10 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.