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REFLECTOR: Slow landings (was:Accident at Santa Monica)



Shawn writes:
>designing a modification that would allow a velocity to 
>slow down to 40 miles per hour. 

Kurt writes:
>Attempting to slow the landing speed of this slick airplane 
>to 40 MPH (only 34.8 knots) would be 
>an engineering challenge if not impossibility.

Joe writes:
> IT GOES FAST.  It's a high performance aircraft!

The hard part is not getting the plane to fly at 40 ... that
would be quite easy. Getting it to fly 40 and  200 is also
possible, but difficult. What is impossible is getting it to
fly at both 40 and 200 (level) with just 200 hp in a simple
configuration.

Yup, that 200 mph number sells airplanes. Being able to do it
with a widely available 180 hp or 200 hp engine is a really
good design point. Very few of the people who actually spend
their money on planes which will go fast also insist that the
planes land really slow.

But how could it be done? I shudder to think of the
complexity which would be needed to integrate flaps on the
main wing with elevators which would also have to act as
flaps to maintain the center of lift in the same part of the
plane ... all while maintaining a margin of safety between the 
main wing stall angle of attack and the canard stall angle of
attack.

I spent almost a year trying to figure out exactly this problem
with the aid of some custom canard configuration software
and an aero guy from NASA. We were only working on what
the wings would have to do from an aerodynamic
standpoint, and we never did get to the mechanical side.

After much work, I gave it up and bought the Velocity kit
because it seems to have hit a good spot ... all things
considered. Pushing the envelope wider (top speed to
landing speed) is really tough in a canard if you do not want
to use a huge amount of power to get the top speed.

Cheers,
David