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Old 10-17-2003 | 02:39 PM
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fly109
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From: Oviedo, FL
Default RE: Luftwaffe Display Thread

Jason,

By the way nice looking bird, I like the single seater as much as I do the double. I too designed my model from the Bentley drawings and as such utilized the scale incedence on the wing and stabilizers. The full scale craft had a little over 3 degrees positive on the wing and 2 degrees positive on the stabilizer. They did this so that at the flare, the aircraft would have an overall flatter pitch to avoid contact with the tail. It was said that to hit the tail that the main wing would have to be at around 16 degrees positive which was was the maximum angle of attack for that airfoil. In this case it was no more of a danger than with a more conventional layout.
This proved to be the case on my model as well in that the landing was very comfortable but the take off run required a bit more length to unstick. Because the model was built for competition I had to use identacal motors front and rear, I had Moki 1.8s which left the model slightly underpowered at 75 pounds.
The talk about the front prop washing out the rear or visa versa is not correct, prop each engine as you would normally do. Some will say the the wash from the front prop will pass at high speed through the rear prop with out gaining any aditional thrust - this is false. In actuallity the thrust from the front engine - as with all front engine drive aircraft- is greatly consumed by the travel down the fuselage. They did tests on the full scale bird and found that when they cut the rear engine and used the front alone, the 335 had a top speed of just over two hundred miles and hour. But when they cut the front engine and used only the rear, this 22,000 pound twin on a single engine was faster than a Mark I Spitfire at nearly 328 miles per hour!
I had a good demonstration of this principal on my first flight, I lost the front engine. When I did, I actually was having an aurgument with my caller (Charlie Chambers) as to wether or not I had lost an engine at all. The feeling was that there is no way I could maintain speed and altitude on a 75 pound podel with a SINGLE Moki 1.8 glow motor (see photo below). Well it did just fine until gear and flaps, at that point I needed full power to maintain about a fifteen degree down angle and had barely enough to flare. In all I flew the model three times before losing it on the fourth take off. I was running out of runway and pulled the model off prematurely and it was severley damaged. I am in the process of building a new model as we speak.
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