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View Poll Results: Will the deployment of the flaps cause the plane to
nose up 5 41.67%
dive 4 33.33%
experience no change in pitch 2 16.67%
explode 1 8.33%
Multiple Choice Poll. Voters: 12. You may not vote on this poll

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Old Feb 01, 2014, 03:20 PM
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Knoll53's Avatar
United States, CA, Marina
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Poll
Pitch neutral flaps

In the FootLoose Floater build, will the deployment of the flaps affect the pitch? Here's your chance to prove yourself ( or your luck ) before the maiden on Monday......no I'm not voting, but you should. check the box and Vote !

Kent
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Old Feb 03, 2014, 01:27 PM
InceCreations
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Joined Jul 2009
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Nose down as (mostly) the flaps are behind the cg.
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Old Feb 03, 2014, 01:34 PM
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Knoll53's Avatar
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But Vincent, don't those flaps also affect the airfoil directly in front of them, thus changing the lift of area of the wing in front of the CG?

Kent
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Old Feb 03, 2014, 02:11 PM
InceCreations
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The flaps I have on some flying wings show nose down event.

Are your flaps behind the cg?
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Old Feb 03, 2014, 02:16 PM
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Knoll53's Avatar
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Quote:
Originally Posted by vincent123 View Post
Are your flaps behind the cg?
That's the $64,000 question......don't know.
Kent
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Old Feb 03, 2014, 02:39 PM
InceCreations
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You don't know where your cg is located?
I saw you footloose hanging on the ceiling, so I m sure you know it
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Old Feb 03, 2014, 02:44 PM
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Knoll53's Avatar
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The CG is at 12.25" from the nose, but the big question is whether or not the flaps and the airfoil that they modify are behind the CG.

Gotta go.....Kent
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Old Feb 03, 2014, 02:48 PM
InceCreations
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Could very well be that with your planform and flap location, your flaps will be neutral.
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Old Feb 03, 2014, 03:49 PM
Herk
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Sooner or later all the science and guesswork ends, experience does what it can; and then the aircraft tells us what really happens. Isn't this fun?
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Old Feb 03, 2014, 06:24 PM
Red Merle ALES
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I think no matter what you'll either need some up or down aileron trim. I've never ever flown any kind of an airplane whether it is a model or full scale that does not need some kind of trim with flap deflection. The amount of trim changes with speed, obviously.

Curtis
PS I did not vote as there is not a correct option, IMHO.
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Old Feb 04, 2014, 03:39 AM
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miniphase's Avatar
Kent, UK
Joined Nov 2004
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It looks to me as if there is more flapped area ahead of the centre of lift (than behind it), so I would expect there to be a pitch up when you deploy the flaps.

Very much looking forward to seeing the maiden Kent...good luck!
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Old Feb 04, 2014, 10:05 AM
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Knoll53's Avatar
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Thanks for all of the responses. So it is clear to me, that I could have been a "little more clear" in writing the poll question. I think that I got more complaints than votes. The only accurate answer would have been "all of the above" which was not offered........(what fun would that be?)

To ask the question accurately probably would have been a page long. I guess what I was thinking was glide path change as it affects landings.

BTW, the flaps are pretty much neutral pitch with a little nose up. I hope to get a video of very slow flight with a slow flap deployment to show the effect.

Kent
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Last edited by Knoll53; Feb 04, 2014 at 05:44 PM.
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