This is exactly like the last mount except I changed the 
aluminum channel to a 4130 steel hat section to meet
Bill's objection to aluminum in case of an engine fire.

I never thought an engine fire would be much of a problem
anyway. By the time that 1/8 chunk of aluminum channel burnt 
through the wires would have melted and the engine would
have stopped. There was and still is a 5/8 steel cross tube
just below this that would easily support the engine along
with the rear mount. Also the rad just below the channel 
would have melted and sprayed steam through out the engine 
compartment. Built in automatic sprinkler system???
There is plenty of room in most engine compartments
for a halon system.

As I said before this member is in almost pure tension.
The stress is very low. Less than 10K psi at 10 G's. 
There is no torque on the member and no verticle bending. 
There is slight horizontal bending from thrust but most 
of the thrust is taken by the aft motor mount. The three 
inch wide  hat section is more than capable of taking 
all the thrust loads in any case.

The dimensions for the KIS version are 30 inches long
for the 4130 steel hat section and about nine inches long
for the 1/2 inch square brace tubes. At least fourteen 
inches out of the center of the thirty inch hat section
is bolted to the bottom of the pan with half a dozen pan 
bolts.

With this configuration it will take ten G's no sweat. 
 
Paul Lamar
 
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