Pro tip: check the torque on those LRU mounting bolts, not just the connector pins

I was doing a post-install check on a new comms box in a King Air last week and found all four mounting bolts were barely finger tight, even though the D-sub pins were torqued to spec. The tech before me must have rushed the final step. That kind of thing can cause a real bad day from vibration down the line. How often do you guys actually break out the torque wrench for the hardware, not just the avionics?

2 comments

2 Comments

elizabeth_chen2d ago

Honestly, that seems like overkill for a mounting bolt. If the connector is secure and the unit is seated, those bolts are just there to keep it from rattling around. A good quarter-turn with a standard wrench after it's snug has always been fine in my experience. Pulling out a torque wrench for every piece of hardware would triple the install time for no real gain.

finleybutler2d ago

Ever sheared one off by going a quarter-turn too far? Asking for a friend who definitely isn't me.