Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.2 9/17/84; site opus.UUCP
Path: utzoo!watmath!clyde!burl!ulysses!mhuxr!ihnp4!houxm!whuxlm!harpo!decvax!genrad!panda!talcott!harvard!seismo!hao!nbires!opus!scott
From: scott@opus.UUCP (Scott Wiesner)
Newsgroups: net.aviation
Subject: High speed snap rolls
Message-ID: <1053@opus.UUCP>
Date: Sun, 27-Jan-85 17:43:30 EST
Article-I.D.: opus.1053
Posted: Sun Jan 27 17:43:30 1985
Date-Received: Wed, 30-Jan-85 08:02:33 EST
Distribution: net
Organization: NBI,Inc, Boulder CO
Lines: 29

To prevent anyone from freaking about about this article, let
me say up front that while everything described applies to any
aircraft, the incident occurred with a radio controlled MODEL.

I flew a new plane this weekend.  I had bought it at an auction
for what seemed like a good price.  As models go, it was a little
overweight for it's size, and grossly overpowered.  (The big engine
was the reason for it's being overweight).

The plane had a tendency to snap roll at high speed.  Whenever I
pulled a little extra elevator, (such as in a loop, etc) the plane
would start snapping.  I decided to take it up to a reasonable high 
altitude to see how it handled at low speed.  As could be expected,
the plane snapped soon after it started slowing down.  The plane started
heading straight down, but was NOT in a spin.  Just flying vertically 
down, with the engine at an idle.   Whenever I tried to give a little
up elevator, it would start to pull out, then do another snap.  I
probably went through this snap/recovery sequence 4 times before it
went in.  

Now my question.  Can anyone out there give me a good explaination
of the aerodynamics that were going on here?  It would seem that 
when at full throttle, quickly changing the angle of atack would 
cause the wing to quickly stall out, resulting in the engine torque
taking the plane for a ride. 
-- 

Scott Wiesner
{allegra, ucbvax, cornell}!nbires!scott