Quote Originally Posted by jtpitkin06 View Post
[rolling eyes in unison with rocket scientist] My tray had #8 size holes.
John
I just reread my post and true I wasn't sufficiently clear. The rocket scientist is back this evening using my hanger to rib stitch his Stearman's aileron that suffered some significant hangar rash that required some rib repair and recovering. Anyway, the reason he wanted to see the calculator was to prove to me that the 4-40 screws in the installation kit were adequate. I suppose from his perspective - extreme engineering and weight saving to the Nth degree - they are, but went to the 6-32 as they are countersunk in the bottom of the tray and larger than that the four heads of the screws would have been the only things contacting the bottom of the ELT.
Lowell