Mailing List lml@lancaironline.net Message #17308
From: Gary Casey <glcasey@adelphia.net>
Sender: Marvin Kaye <marv@lancaironline.net>
Subject: ice on balance weights
Date: Fri, 24 Jan 2003 09:58:37 -0500
To: <lml>
<<The builder redesigned the rudder and eliminated the vertical
portion of the rudder / vertical stabilizer gap altogether (see attached
picture).  I spoke extensively with the owner on this subject and I believe
his motivation was to increase the lever arm of counter weight and therefore
reduce the required ballast.>>

The plane looks very nice, but I have two reservations:  First, could the
accumulation of ice on the leading edge cause an aerodynamic instability of
the rudder?  I doubt it, but it is possible, I suppose.  There are lots of
IFR Pipers flying with the whole "elevator" leading edge exposed and I have
never heard of a problem.  Second, I would think that ice could still build
up on the sharp edge of the balance weight that is diagonal to the air flow.
I have been thinking about also rounding this edge.

Just to add another observation:  On most Cessnas the elevator balance
weight is bent downward compared to the elevator.  The theory being that in
normal cruise the plane is trimmed nose down (the elevator has a slight
downward deflection) and this keeps the balance weight fair to the
stabilizer.  Why didn't they just change the incidence angle of the
stabilizer?  I was told that they found that the drag was slightly less with
a little down deflection of the elevator.

Gary Casey


Subscribe (FEED) Subscribe (DIGEST) Subscribe (INDEX) Unsubscribe Mail to Listmaster