BLUF: Only hand-tighten egress knobs on the HMEE-1 and do not use solvent or petroleum-based products on ballistic glass.
Photo by Scott Sturkol
Motor sergeants, have your operators pay close attention to the HMEE-1’s egress window WARNING and CAUTION shown with Item 3 in the PMCS information in WPs 0009-6 and -7 of TM 5-2540-236-13&P (Jul 16).
The warning says:
Only hand-tighten egress knobs. Overtightening knobs will prevent egress window from being opened. Failure to follow this warning may cause injury or death to personnel.
The caution says:
Do not use solvent or petroleum-based products on ballistic glass. Failure to follow this caution will cause damage to ballistic glass.
Additionally, it’s important to open the windows periodically to ensure the egress knobs turn without difficulty and watch for and then mitigate corrosion.
A few years back a near-fatal accident occurred when a vehicle rolled over into a body of water. The operator quickly realized the cab’s egress window turn knobs were corroded and hard to turn as he tried to escape. Turns out the windows were never opened. Over time, the window seals created a vacuum, preventing the windows from opening. With no time to spare, he had to kick the rear window out just to escape!
It’s almost certain that the corrosion on the knobs would have been detected when inspecting the knobs to ensure they weren’t over-tightened. That’s why it’s important to read and heed all WARNINGs and CAUTIONs in the TMs.