Airplane design.

"Stuart Grey" wrote in message
...
Montblack wrote:
("Richard Lamb" wrote)

Design an airplane within the 254 pound weight limit.

Clean sheet of paper.
254 pounds empty weight.
Your choice of engines, design, materials.

Where would you start?



Cri-Cri type
Twin diesels - torque, torque, torque
Wings that rock - "control wing" "free wing"

http://www.flyingflea.org/docs/SprattControlwing.htm

http://www.airandspacemagazine.com/ASM/Mag/Index/1995/DJ/ssfw.html

Original CriCri's weighed approx 150lbs, that included two 9hp engines.
150 lbs - total!

150 lbs - (15# engine + 15# engine) = 120 lbs - 20 lbs other stuff = 100
lbs of plane building material.

So I'm thinking ...how much would (guessing) 60lbs of Titanium cost?


Montblackium


So, why did they put two engines on that small of of an airplane?
Was it to get around the 61 kts stall speed requirement? (I believe two
engine airplanes don't need to meet that...) Or was it just because they
could?

I really don't know either. But it is a pretty old design, so it is
possible that the designed was simply not aware of a suitable single engine
at the time. It is also possible that there was concern about the fuselage
reducing the thrust of a very small prop--the props do operate in relatively
undisturbed air and have plenty of clear space behind them.

To the best of my recollection, the designer really was an aeronautical
engineer--which I am not.

Peter