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                           TeamGrumman-List Digest Archive
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                     Total Messages Posted Tue 02/24/04: 1
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Today's Message Index:
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     1. 10:14 PM - cracks  (TeamGrumman@aol.com)
 
 
 
________________________________  Message 1  _____________________________________


Time: 10:14:39 PM PST US
From: TeamGrumman@aol.com
Subject: TeamGrumman-List: cracks

--> TeamGrumman-List message posted by: TeamGrumman@aol.com

I just started an annual on a 76 Tiger.   4000 hours.   No cracks.   
Seriously.   No cracks.   

Based on what the DER has told me, it's the rudder being deflected hard as in 
a slip or ? that causes the most twist in the torque box formed to support 
the horizontal.   The action of the rudder deflection is passed primarily 
through the rear bulkhead.   Then the section between the rear bulkhead and the

horizontal support tries to follow.   The large horizontal tries to follow and
the 
inertia is absorbed in the skin of the empenage.   Had the vertical supports 
(to which the horizontal is attached) been properly tied to tray (called the 
horizontal bulkhead) on which the ELT is mounted, the torque would have been 
more effectively transmitted to the fuselage and that section would not have 
flexed (referred to as 'racking') and would not have caused cracking in the lower

stiffener.   The fix we are working on forms a lightweight bulkhead 
(semi-solid) across most of the section.    

Tail dragger anyone?   With the tail strengthened ....

Also, IF YOU KNOW OF ANYONE WHO HAS A REAR SECTION THAT CAN BE DONATED FOR 
FITTING THE BULKHEAD, PLEASE LET ME KNOW.   ALL I NEED IS THE LAST 20-24 INCHES

OF THE FUSELAGE.

GARY