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Twin Dreams:


 

 

The possibility of a twin Velocity has always been very attractive. It would be like having ones own mini Starship. Antonio expressed an interest right at the beginning of the Velocity project and I spent some time exploring the implications.


The idea was to use two Franklin 200HP engines. This was changed to Twin ATPI turboprop engines after the calculations showed some serious CG problems. The X-Plane model shown in these images flew very well with good single engine performance. The Vmc was a little on the high side, but this could be controlled using a keel fin fitted with a trim surface and mounted below the cowling. Unfortunately ATPI could not supply a hydraulically controlled propeller with their engine, and it was decided that the MT electrically controlled propeller could not feather quickly enough in the event of an engine failure. The twin project was abandoned when ATPI promised a single engine with 300HP. That engine did not materialize in time, hence the move to a T58-8F based turbojet engine.