How not to do the rubber bushing in the firewall trick.
This puts huge local bending loads on the
firewall. Of course the firewall can be beefed 
up with large heavy metal bolt brackets but why? 
I did not see any however.

If you put the bushings in the firewall instead 
the local bending loads on the firewall are 
near zero with a lighter weight design. The 
tension, compression and shear loads, in the later case, 
are distributed into the composite firewall in 
a highly favorable manner. Far superior in fact 
to merely bolting the metal motor mount to the firewall.

 Also it makes no sense to have four lower
mounts for a total of six! The one thing he did right
hopefully is tie the lower firewall mounts back to the
landing gear (I hope.)

It totally escapes me why this was done this way.
Perhaps he did not know about Barry mounts and all he
had were Lycoming rubber bushings. 

Still???? Sheeesss! The owner was not around.

Oh well too late now. Hopefully it won't fall off.

Paul Lamar
 
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