Re: questions on multi-wing planforms

Re: questions on multi-wing planforms

  Home | Guides | Register Now! | Search | About
 rec.aviation.homebuilt    Post an article   get this group's latest topics as an RSS feed add this group's latest topics to your My MSN content add this group's latest topics to your My Yahoo content
 Re: questions on multi-wing planforms Jim Logajan Reply Send to a Friend   Print
 
Subject Author Date
questions on multi-wing planforms pTooner 06-23-2006
"pTooner" <geddings@bellsouth.net> wrote:
> Firstly, I'm new here although I have been reading for a few days. For
> anyone with more knowledge than I, I keep considering building a small
> 4 wing aircraft. Not stacked, but two up front and two in the rear.
> I've read frequently of problems supposedly resulting from
> interference of the airflow between wings, but I cannot seem to find
> anything very specific.

Theory of biplanes might provide the theoretical basis. My copy of
"Theoretical Aerodynamics" by L. M. Milne-Thomson discusses wing
interference between the wings of biplanes in chapter 8. (It's a Dover
publication, so it is still in print and inexpensive.)

Also, try a Google search on this set of search words (with or without
the search word "stagger"):
aerodynamic gap biplanes

> I am fairly confident that interference
> between the front wings (or rear) can be minimized by reasonable
> spacing and differing dihedral.

Staggering the wings tends to help reduce interference also.

> I am not sure what the effect of the
> airflow coming off the front wings will have on the rear set. I do not
> know whether I could remove most of the problem by having one set
> considerably higher (how much?) than the other set or if it is
> reasonable to have them on more or less the same height.

I suspect having one set high that the other would equivalent to a large
staggering angle.

> The reason
> for the concept is trying to get a wingspan small enough to fit into a
> normal garage and conceivably take off and land from streets and
> highways. I visualise something in a two place plane that would fall
> into something of the appeal category of a motorcycle or small sports
> car. Any thoughts would be appreciated.

If you are not already familiar with it, you should browse this site,
which include planes that attempt to satisfy some of your requirements
(the Wernicke Aircar uses low aspect ratio wings to try to meet some of
your requirements):
http://www.roadabletimes.com/


other useful resources:
Government National Mortgage Association - Ginnie Mae
The National Home Equity Mortgage Association
Fannie Mae Mortgage
Movie-Corner.com Movie Blog