I've heard that you shouldn’t walk underneath the main gun of an M1-series tank because it could suddenly drop and cause a serious injury.
However, I’ve only ever seen tank gun tubes drop slowly as hydraulic pressure is released. Is rapid gun tube drop really a concern?
Yes, it is. TACOM says that walking underneath a tank’s gun tube is dangerous for several reasons.
First, if someone just happens to be walking underneath the gun tube while a Soldier is inside the tank operating the main gun, that person could be hurt if the gun tube depresses.
Second, depending on where the gun tube is in relationship to the reticle during certain testing of the fire control system, and when the power control handles are engaged, the gun tube could suddenly slam downward.
Lastly, mechanical pieces of equipment always have the potential for an unforeseen failure. In other words, everyone should stay out from underneath the gun tube.
Better safe than sorry!