[1][2][4] Both aircraft were constructed as pure gliders and then later motorized with the addition of a twin-cylinder, in-line Yamaha snowmobile engine.
The engine is mounted behind the wing spar on a pylon that retracts forward into a bay closed by two doors.
The pylon can be deployed in eight seconds and uses the electric motor from a Ford Thunderbird window winder.
[2] Oldershaw's O-3 was listed by the Federal Aviation Administration as destroyed and removed from the register in July 1999.
[5][6] O-3 serial number 2 was built by Carlton Kibler of Porterville, California and officially registered as a Fry-Kibler O3A Renigade in 1979.