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Author Topic: Foward Swept Wing  (Read 2652 times)

Offline Sweet B

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Foward Swept Wing
« on: September 17, 2020, 12:26:54 PM »
Guy,

I need some input on this one . First the disclaimer: The plane is a project take over.  Ok, I've noticed when the wings were assembled they were out of square probably about 1-1/4 so when installed I have a slight 1-1/4 forward sweep to the wings. Do you thing this would create any adverse affect with stability?     

Offline Hugh Sistrunk

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Re: Foward Swept Wing
« Reply #1 on: September 17, 2020, 01:30:36 PM »
I can't see where this will cause you any problems - I would like to see that both wing tips are equally forward, if so and the proper and equal dihedral, wing incidence and washout is used, I think your good to go... Someone else on here may have more info.. have fun.

Offline Chuck in Indiana

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Re: Foward Swept Wing
« Reply #2 on: September 18, 2020, 02:48:53 PM »
Forward sweep is not a bad thing. It gives some dihedral effect. Don't worry, be happy.  :)

Offline Chuck in Indiana

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Re: Foward Swept Wing
« Reply #3 on: September 19, 2020, 09:28:27 AM »
Just to add to this. If you want to get them straight.. it would be fairly easy to make new root fittings. If you do that, you could rig it as you want.

Offline kennyrayandersen

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Re: Foward Swept Wing
« Reply #4 on: September 19, 2020, 05:47:11 PM »
Cosine of a small angle is almost 1. 1.25" over the length of a wing will give you a pretty small angle, so any kick loads due to the small angle will also be small.
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Offline jrbirdman47

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Re: Foward Swept Wing
« Reply #5 on: September 20, 2020, 03:06:18 PM »
I do know that on certain WW2 training planes they changed their wings (Leading edge) to sweep slightly aft to make them less stable at high angles of attack to mimic the tendencies of higher performance planes like fighters which tended to "depart from controlled flight" when handled improperly. Don't know what forward sweep would do.

Offline kennyrayandersen

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Re: Foward Swept Wing
« Reply #6 on: September 21, 2020, 01:24:06 AM »
If the wing is forward swept, the outer part of the wing can 'catch' air, and then it deflects, catching even more air. It's an aero-elastic thing. There have been a few demonstrators, but there is a reason you don't see them as a usual configuration. With fighter aircraft they also move the CG to be aft of the lift center, which makes them unstable, but very responsive -- computers can make rapid minute adjustments to keep them flying. That ain't like what we have. The tiny amount the oP is showing though won't make much difference.
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Offline Chuck in Indiana

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Re: Foward Swept Wing
« Reply #7 on: September 21, 2020, 04:36:44 AM »
Bery Sisler's Cygnet has forward swept wings. I've flown one, and it flies normally.  :) As I first said, not to worry, but if you want to make them straight, it is easy enough to do.

 

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