From: CHRISTOPHER_ZAVATSON@udlp.com
Date: Wed, 18 Nov 1998 07:07:07 -0600
Message-ID: <0017B120.C21254@udlp.com>
Subject: Aircraft Jacks
To: Lancair.list@olsusa.com
Mime-Version: 1.0

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     I must put in a plug for the jack pads as provided in the 320/360 kit. 
     As shown in my standard kit (slow build) manual, loads would not be 
     sufficiently transferred from the pads to the structure.  I extended 
     all the bid plies that create the fuselage/wing spar junction down 
     across the jack pad.  I overlapped the plies coming down the side of 
     the fuselage and those coming down the rear of the spar.  This creates 
     something like a 20 ply lay up in the corner right above the pads.  
     Jacking loads are thus nicely distributed along the spar and fuselage.
     
     I agree with the comments warning against lifting the plane from the 
     engine lift ring.  There is probably a good reason 6 cylinder 
     Lycomings have 2 lifting rings.  Also you generate large bending 
     moment in the fuselage center section, similar to a high negative G 
     maneuver.
     
     Chris Zavatson
     N91CZ