Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.3 alpha 4/15/85; site cae780.UUCP
Path: utzoo!decvax!linus!philabs!prls!amdimage!amdcad!cae780!rje
From: rje@cae780.UUCP (Bob Evans)
Newsgroups: net.aviation
Subject: Flaps and Slips in Cessnas
Message-ID: <1363@cae780.UUCP>
Date: Fri, 20-Sep-85 16:49:55 EDT
Article-I.D.: cae780.1363
Posted: Fri Sep 20 16:49:55 1985
Date-Received: Mon, 23-Sep-85 16:19:48 EDT
Distribution: na
Organization: Tektronix, Inc. (CAE Systems Division), Sunnyvale, CA
Lines: 36
Keywords: Slips Flaps Cessna

I know I'm coming in on the end of this discussion, but since I happen
to have the manuals for the airplanes, I thought I'd slip :-) in my
two cents worth. I have manuals for
  1980 C172-RG
  1982 C172-P
  1892 C182-R
  1983 C152
In only one of the manuals are slips and flaps mentioned together -
The 1982 C172-P. The manual says "Steep slips should be avoided with
flap settings of greater than 20 degrees due to a slight tendency for
the elevator to oscillate under certain combinations of airspeed, sideslip
angle, and center of gravity loadings". The manual also calls for a placard
located near the flap extension lever "avoid slips with flaps extended".

All of my time (150 hours) has been in Cessnas -152, 172, 172rg. Only in
the ships with 40 degrees of flaps (all 40 degrees used) have I ever 
noticed the oscillations mentioned - it appears to have about a 1 to 2 foot
amplitude. The conditions were - full fuel, forward CG, steep descent
with full (controls full over) slip, airspeed 60 knots. The oscillations
have a period of about 1-2 seconds. There never _seemed_ to be any
danger of loss of control. BTW my instructor (ex-navy fixed wing, helo, CFII)
said that the oscillation was caused by momentary blocking of the airflow
over the elevator, but that it was obviously :-) self-correcting ...

At any rate, I've never experienced any problems due to slipping with
the flaps out.

Bob


FROM:   Robert J. Evans, CAE Systems Division of Tektronix, Inc.
UUCP:   tektronix!teklds!cae780!rje
	{ihnp4, decvax!decwrl}!amdcad!cae780!rje 
        {nsc, hplabs, resonex, qubix, leadsv}!cae780!rje 
USNAIL: 1333 Bordeaux Drive, Sunnyvale, CA  94089 [until we move ... soon]
AT&T:   (408)745-1440 [until we move .. soon]


Brought to you by Super Global Mega Corp .com