Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!tut.cis.ohio-state.edu!att!cbnews!military
From: jake!wcarroll@encore.encore.com (William Carroll)
Newsgroups: sci.military
Subject: Re: Soviet Wing-in-Ground Effect Machine?
Message-ID: <1990Jul25.004935.7662@cbnews.att.com>
Date: 25 Jul 90 00:49:35 GMT
References: <1990Jul23.203523.8039@cbnews.att.com>
Sender: military@cbnews.att.com (William B. Thacker)
Organization: AT&T Bell Laboratories
Lines: 40
Approved: military@att.att.com



From: jake!wcarroll@encore.encore.com (William Carroll)
>From article <1990Jul23.203523.8039@cbnews.att.com>, by dps@otter.hpl.hp.com (Duncan Smith):
> / otter:sci.military / tek@CS.UCLA.EDU (Ted Kim (Random Dude)) /  5:09 am  Jul 18, 1990 /
>>The other model had what looked like a row of jet engines
>>mounted on a low wing in front. The thrust from the engines was
>>supposed to blow over the main wing to provide more lift.
> 
> This sounds to me like trying to blow a sailboat along with a fan
> mounted on the stern, pointing forward ... The wing could never rise
> through the engines' jetstreams, could it? Am I missing something here?
> I've heard of diverted thrust (blown flaps?), as in the YC-14, but this 
> doesn't seem to be the same principle.

Its known as the Cuanda (sp?) effect. The air flowing over the wing wants
to follow the trailing edge, getting curled down as it leaves the wing's
surface. This results in a vertical force component.

air   ______________ ___
                    \
wing  ------------- |
                    |

It is the same effect that causes the water to run down the glass and make
a mess when you try to pour out a little bit.

It was my impression that the USAF built a STOL prototype that employed
this technique, but I my memory may be failing me there.

I don't claim to understand this, fluid dynamics was one of those physics
subjects I never really understood. Perhaps one of our aerodynamics types
can shed more light on the subject.



William R. Carroll  (Encore Computer Corp., Ft. Lauderdale FL)
wcarroll@encore.com         uunet!gould!wcarroll
   "Dan Quayle gives underachievers a bad name."
                                  -- Bart Simpson