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Old Dec 29, 2012, 06:14 PM
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centennial/aurora colorado
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Quote:
Originally Posted by xlcrlee View Post
Look at the jet engine intake angles, and note that the outboard engines are set to take in air approaching from a steeper up-angle [outboard inlets more downturned > relates to my washout "tirade" ].

Your small model should need even more downturn [higher AoA].


L
just so you know a 747 does not cruise at the angle that picture shows, it cruises at a 3 degree angle.
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Old Dec 29, 2012, 06:22 PM
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Zurich
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Originally Posted by kelloggair View Post
just so you know a 747 does not cruise at the angle that picture shows, it cruises at a 3 degree angle.
I perhaps stupidly assumed that everyone knows that and would mentally rotate the photo .

All my input has been of the airflow at various wing sections .... relative to the body of the plane, not to the angle of the body. But in truth, relative to the ground, the wings of a small slow-flying model of that type in level flight will be at an angle greater 3°....

Lee



the nose Pitot tubes show the onflow there, which will be at best -5° for a small model with scale wing planform
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Last edited by xlcrlee; Dec 29, 2012 at 06:59 PM.
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Old Dec 29, 2012, 08:09 PM
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United States, TX, League City
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I think due to the size I can actually make the "flaps" fixed to give more lift
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Old Dec 29, 2012, 08:44 PM
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Originally Posted by hi2nr View Post
I think due to the size I can actually make the "flaps" fixed to give more lift
You could eaither also extend them rearward and curve them in scale multi-steps, but not necessarily in FULL-flap position.

One possibility would be to have slipped-on removable flaps, without changing the T.E. you've built.

Another would would be to have two diff., insertable flaps, one set in the retracted position, useful for wind, and the other in maybe 15% or 20% up to max 30% flap position [the latter only for small indoor spaces].

OR, a hand-movable, extendable flap-system. Might be impressive.

In ANY case, I'd first try it with taped-on simple flaps to get a rough idea of size and function ....


Lee
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Old Dec 29, 2012, 08:57 PM
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I have vinyled on some mock up "extended" flaps and also used it to increase the trailing edges of elevator/aileron surfaces. Awaiting the morning to test out the increased surface areas!
Quote:
Originally Posted by xlcrlee View Post
You could eaither also extend them rearward and curve them in scale multi-steps, but not necessarily in FULL-flap position.

One possibility would be to have slipped-on removable flaps, without changing the T.E. you've built.

Another would would be to have two diff., insertable flaps, one set in the retracted position, useful for wind, and the other in maybe 15% or 20% up to max 30% flap position [the latter only for small indoor spaces].

OR, a hand-movable, extendable flap-system. Might be impressive.

In ANY case, I'd first try it with taped-on simple flaps to get a rough idea of size and function ....


Lee
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Old Dec 29, 2012, 10:53 PM
ich bauen groß modell flugzeug
Keenan smith's Avatar
United Kingdom, London
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you should move this to the Airliner forum
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Old Dec 30, 2012, 05:42 AM
TheyreComingToTakeMeAway!
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i think your props are on backwards in the photos, thats not how you flew it right?
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Old Dec 30, 2012, 05:52 AM
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Zurich
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Originally Posted by derk View Post
i think your props are on backwards in the photos, thats not how you flew it right?
Cool tip for everyone! An excellent way to get that extra bit of performance out of your aircraft > put the props on correctly [or turn the plane around]

L



[actually, years ago when testing a newly designed & built small plane with a COX .020 at the COX factory using their factory-fresh fuel with evidently far more nitro in than what reaches the consumer at the end of the marketing pipeline .... the ONLY way to get that sucker to fly in an unscary manner was to put the prop on backwards!]
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Old Dec 30, 2012, 08:55 AM
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Hi2nr Your micro 747 is amazing Sir.
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Old Dec 30, 2012, 09:35 AM
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Hi2nr Your micro 747 is amazing Sir.
a b s o l u t e l y !

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Old Dec 30, 2012, 10:38 AM
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I actually flew it both ways, flys the same or nothing noticeable to me. Plane didn't need much power to glide around lol
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Old Dec 30, 2012, 10:51 AM
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Originally Posted by hi2nr View Post
I actually flew it both ways, flys the same or nothing noticeable to me. Plane didn't need much power to glide around lol
w.r.t. backwards props, washout, turned-around plane or ....?
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Old Dec 30, 2012, 01:27 PM
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WOW!!!!!
Amazing.... could you move this one to the airliners section?
(there are a lot guys that have to see this baby)

Just great.

Thanks for sharing
Markus
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Old Dec 30, 2012, 05:54 PM
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United States, TX, Whitehouse
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That looks amazing I tried once( not a small one ). Didn't work out. Good lick to you though. Look like it will work!!
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Old Dec 30, 2012, 10:00 PM
as the name says!
AirplaneFreak100's Avatar
Barbados
Joined Sep 2012
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Jeez wish i was as skilled as you
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