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REFLECTOR: Adjustable air intake



Simon you fiend!!
We were talking about armpit scoops and you mentioned adjustable
intake scoops.  You know I have a soft spot in my heart for gizmos.

What did I do?  Well, check out
http://www.awpi.com/michalk/pics/airintake.gif

I took the plans shown above and cut out all of the foam for this.
it was very easy to figure everything.  It took a couple of hours
of thinking.  I have pictures of how it looks glued to the 
airplane.  I'll scan them in if I can tomorrow.

Here's what I figure:
Equipment I have:
	two batteries, one main, one backup
I mention this because I want to use electrical actuators to run
these things.  They will be connected to something like a PIC.
Small and cheap.  Actually two PICS, one for each intake.  If a PIC
dies, or an actuator dies, the other intake should function just
fine.  If my "avionics" battery goes, I have an emergency crossover
switch, so the air intakes still operate.  Assume they just
quit, and I'm really having a bad day.  The intakes are stuck
in the last position they were at.  All of these options indicate
that in a failure I won't overheat my engine.  Why PICS?  Well,
I want it to be completely automatic, to be done without
any pilot supervision.  Point the nose downhill, and let the
computer keep the engine from shock cooling.

The intake for the Franklin plenum is 4 inches in diameter ...
or so I'm told.  I assume it has two intakes.  4" diameter
gives approximately 12.5 in^2 of area.  The opening in the
cowl is a 6"X2" opening.  The variable ramp is adjustable
from 0 square inches to 36 square inches.

If you look at this from the front and calculate the total area
seen by the wind, it's going to be about 16.25 square inches.
I'm not sure if that is what you call flat plate area.

Let me know what you think.
-- 
Brian Michalk  <http://www.awpi.com/michalk>
Life is what you make of it ... never wish you had done something.
Aviator, experimental aircraft builder, motorcyclist, SCUBA diver
musician, home-brewer, entrepenuer and SINGLE!