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Old 06-06-2017, 01:36 AM   #73 (permalink)
sidecar
EcoModding Lurker
 
Join Date: Oct 2011
Location: Australia
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Quote:
Originally Posted by Bicycle Bob View Post
The biggest problem with roadable aircraft seems to be available lane width vs the wingspan needed for efficiency. Lifting bodies are nice and neat, but draggy without wing extensions.
This is absolutely true, beyond 6-7ft wide and the vehicle is quite unmanageable on the road, so it needs a form of folding geometry to establish a useful aspect ratio or it wont ever leave the ground without a pile of HP for thrust.

As soon as one does that, air circulation around the wing tips sees it as no different to the full wing span, even though the bulk of the area is the lifting body. The lifting body comprises more than enough area to feather the winglets within its form for road use for a profile more consistent with road use.

Another issue discovered by solar race cars whose body form is a sleek aerodynamic profile, is inland gusts of wind. Such cars crossing the Australian desert were at risk of destruction because the car was liable to leave the ground and flip. Assist crews would have to hop out of the support vehicle and hold the car on the ground to avoid annihilation.

Clearly your flying car wouldn't be likely to have a support crew, so some attention needs to be paid to that phenomena. The single rear wheel on a motorcycle like swing arm can control the bodies angle of attack between on road use and flying configuration.

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