The modest amount of thrust available from the EDF-50 pretty much dictates a minimalist design—there's not much slack in the budget for the extra weight and thrust losses of air intakes and an aft fuselage/jetpipe. Weight and balance considerations constrain the motor location to lie close to the center of gravity.

A V-tail was adopted to carry the control surfaces well clear of any flow disturbances and fan exhaust. The highly cambered airfoil section was chosen for a high lift co-efficient.

The resulting aircraft is unconventional looking, but the wing loading thrust/weight ratio, projected control surface volumes, and C.G. location are reasonable. The double expansion at the underside of the wing leading edge/fuselage junction probably causes a flow separation that increases drag and reduces thrust, but this does't seem to have any serious effect in practice.

The carbon fiber spar flange is inlet into the top of the wing to present a smooth surface to the airflow.

After the control throws were reduced, flight testing revealed that performance and handling was much better than expected.

The aircraft was designed to fly indoors, but the present configuration is not optimum for that purpose. It is too fast, and needs to be flown at 1/4 to 1/2 power setting with about 0.10" up trim. The test pilot, Ian Brooks, reports that it "just sits there" at low power settings, but gets squirrelly at high power.

If the aircraft was to be flown excusivly indoors, the ruddervators could be set at negative incidence to cancel out the up trim. The aircraft does not appear to have any tendency to side slip into the ground in turns.

The aircraft flies outdoors with the trim set to neutral. It can be rolled (NOT RECOMENDED), looped, and is fast, stable, and points instinctively.

• Download plan TOP
• Download plan SIDE
• Download plan FRONT
• Download plan ISOMETRIC
• Download plan Weight & Balance

SHORT CLIP