Flapper

 

Flapper - plan thumbnail image

Flapper - completed model photo

Flapper  
by Art Horak
from Model Airplane News
July 1945 
38in span
Tags: Rubber F/F
all formers complete :)
got article :)


Submitted to Outerzone: 07/05/2013
Outerzone planID: 4346 | Filesize: 251KB | Format: • PDFbitmap | Credit*: ErikJohnson

   

About this Plan

The Flapper - Ornithopter. National record holder.

Quote: - "After trying various ideas and different aerodynamic setups I finally arrived at the following conclusions: 1. It must have a large stationary suarface with a high lift airfoil set at a high angle of incidense. 2. it must be extremely light but strong 3. it must be streamlined in order to permit fast flights. Speed is essential since lift increases with the square of the velocity... "

Direct submission to Outerzone.

Update 28/02/2017: Added article pages, thanks to George.

Supplementary files

Article.

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User comments

Having built Dr. Lippisch's 48 inch version, which probably preceded Horak's version by 10 or 20 years (unlikely he was a Dr. yet), I'm naturally interested in the Flapper. I can plod my way thru it, but a text would be really helpful if there were any available.
ArtHoltzman - 13/08/2013
This plan (and article) is in the July 1945 Model Airplane News.
George - 28/02/2017
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Notes

* Credit field

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Scaling

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