Wing section

[Erfolg]

Has anyone experience of using Eppler 182 on a plank, for the purpose of gliding. I intended a span of approx. 2m. with a chord of 300mm. I have printed out a copy of 8.8% E182 from the Profi programme/site. It seems about the same thickness of the Windfreak section, although the Windfreak appears to have the maximum camber near the leading edge. Also the camber appears to be less as the leading edge is lower, the reflex also is considerably longer about 40% of chord. I would use the windfreak section except I have only a small scale drawing to work from (I believe this section at least works, it is based on something called the Aquilla so I have been told).

I have used Eppler 186 previously with very poor results 100inch span with a 14 inch chord, Foam cut wing. Towing was poor, in that not much height could be gained. The glide slope was also very poor.

I intended to build an electric glider, using a 200W motor and li-po battery. I therefore want a good section. By good, it needs to have the ability to glide, good penetration, without a sudden unpredictable stall.

Can anyone help?

[Seamus O'Leprosy]

Sorry cant help on that one

[Simon Chaddock]

Erfolg

Not quite sure why you would use E182.

It has a rather poor maximum L/D (29) and low stall angle 5.5 degrees here but being thin I presume it has good penetration.

Other Epper sections like E395 have over twice twice the maximum L/D coupled with a higher stall angle.

 

You pays your money and you takes your choice!

[stephen wenban]

 

HS 3.5/12 © Hartmut Siegmann

1.00000 0.00000

0.95000 0.00812

0.90000 0.01475

0.80000 0.02870

0.70000 0.04250

0.60000  0.05902

0.50000 0.07516

0.40000 0.08901

0.30000 0.09500

0.25000 0.09415

0.20000 0.09099

0.15000 0.08380

0.10000 0.07120

0.07500 0.06233

0.05000 0.05050

0.025000 0.034490

0.020780 0.031161

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0.012500 0.023690

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0.001110 0.008365

0.000000 0.000000

0.004373 -0.008567

0.012500 -0.014730

0.016577 -0.016206

0.020762 -0.017092

0.025000 -0.017700

0.05000 -0.02102

0.07500 -0.02250

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0.70000 -0.03061

0.80000 -0.02392

0.90000 -0.01450

0.95000 -0.00811

1.00000 0.00000

The eppler section has a bad habit of chamging pitch as speed increases you be forever retrimming at different speeds

The HS section coords above are for a large tailess project 

 

 

Edited By David Ashby - RCME Admin on 09/02/2012 14:25:25

[PatMc]

Erflog,

Martin Hepperle's site has a section on flying wing aerofoils with a lot of tech info that you might find useful.

[Former Member]

[This posting has been removed]

[ken anderson.]

someone has posted on this page and duffed it up-big style...........

 

ken anderson ne..1..... page dept.

[Tim Mackey]

Fixed by David I think ?

[stephen wenban]

This is the second time this has happened and its my post edited I've never had any problem with thousands of post on many many forums I belong to . That post was no different to any post I've made so there something strange with the forums setup I think I'll give a miss

[Tim Mackey]

Stephen, theres nowt "wrong" with the forum but it does have a few little quirks .... one of which is that if you try to paste stuff from another document or webpage etc, you must use the "Word" icon on the toolbox ( third from the right ) to ensure correct formatting.

 

[stephen wenban]

Thanks Tim but its a strange setup and really fussy seem really clunky compared to other forum set ups ,best way is not to post links or paste documents obviously . I apologize for the interruption to the normal posting .