Thread: Discussion Alpina Magic
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Old Nov 18, 2012, 07:28 AM
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I care about rising air !
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West Chester, Ohio
Joined Feb 2002
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I have...
Although it was not an Alpina "Magic", but an original 4m Alpina, which has the same Ritz 2 airfoil.

At the time, I was flying the Alpina on a slope with a very small landing area.
Even though my Alpina had spoilers, landing always was tricky, because our landing area was so small.
So I started thinking about adding flaps, to be able to use crow braking.

At the time, through the german rc-network message board, I managed to get into touch with the designer of the Alpina, Hans Glatthorn, and I asked him.

His answer basically was :
"Sure, why not. ? Even though the Ritz 2 is not specifically designed to make use of camber-changing flaps, being able to do so, will have benefits.
After all, an aileron also is nothing more than a camber changing flap, you deflect the aileron, and by doing so, change the airfoil's camber in that area, which then produces more ( or less ) lift... Wing goes up ( or down ) "

So, I went ahead and cut out flaps on the traling edge, from 1" of the root all the way to the aileron, with 15 % or 20 % of the chord, can't remember now, and unfortunately, that Alpina wnet into the "big hangar in the sky" a long time ago....

And it worked pretty well. Reflex, i.e. raising the whole trailing edge, did not have much of an effect, lowering the whole trailing edge 2-3 mm made the Alpina noticably slower, and able to circle in narrow thermals.

Crow, lowering the flaps 60-70 deg, and raising the ailerons about 30 deg, worked really well, allowing steep and slow approaches, exactly what I needed for our small landing field, although in crow, she bacame somewhat sluggish in response to aileron inputs.

All in all, it worked for me, even though the Ritz 2 is not specifically designed for camber changing flaps, they still have benfits. May be not as much as on a modern airfoil, but nevertheless..
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Last edited by MTT; Nov 18, 2012 at 07:43 AM.
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