- AAI - American Autogyro - Sparrowhawk Gyroplanes
- Air Command
- Air & Space 18A
- Auto-Gyro GmbH
- Aviomania
- Bensen Style
- The Butterfly
- Concept Machines
- Gyrobee and Related Designs
- Helicopters
- Helicycle
- Magni gyroplanes
- Mosquito Helicopters
- Phenix Tractor Gyroplane
- RAF - Rotary Air Force
- Rotor Flight Dynamics - Dominator
- Single Place Designs
- Sport Copter
- Tractor Designs
- Two Place Open Machines
- Two Place Enclosed Machines
- Ultralights
- Xenon