[dragoon500ly]

IIRC, the M-1 was the first operational tank to use blow out panels. There was a nasty accident in Germany in 1985-86 during a Table VIII Night Gunnery exercise in which the crew of one tank fired a TPDS round into the turret rear of another tank about 150 meters or so in front of them.

I was in the admin area preping for my turn down range when we saw the fireball. Almost as soon as Range Control was screaming "Cease Fire!", my tank and two others as well as the ambulance and Safety Officer were heading down range to give what aid we could.

When we arrived, the tank was on smoldering after the halon extinguishers had fired, and bits and pieces of shell casings, ammo racks and the blow out panels themselves were scattered over a rather large area. Remembering stories I had read about, I was expecting the worse when the loaders and tank commanders hatches swung open.

All four crew members were shaken up by the concussion and were flown to the Grafenhower aid station, they were back with the unit the next day.

Inspection of the tank showed no charring and only minor damage inside the crew compartment. The tank was driven back to the main post motor pool for a more detailed inspection.

As to what happened, there was a certain Platoon Sergeant who had returned to tanks after eight straight years of recruiting duty. As an "experienced tanker" he failed to attend the training classes on the IPM-1 and had his gunner initial him as completing all classes. It turns out that he wasn't supposed to have his weapons loaded (and was still displaying a green light to confirm his unloaded and weapons elevated status). Not used to the thermal sight, he thought that the tank on the firing line was a heated target and put a training round almost dead center of the turret rear. Kudos for a great shot! But this E-7 was found guilty of several charges and sentenced to eight years for disobeying a lawful order and negilance. Demoted to E-1 and a bad conduct discharge...after having served 17 years! His gunner was busted from E-5 to E-1, and got to spend four years at Fort Leavenworth before getting his BCD. The Platoon Leader, Company Commander, the Safety Officer and the Training Officer all received letters of repimand, signed by a lieutenant general (ending their careers) for failing to properly oversee training.

And before some asks how a TPDS round penetrated armor, please remember that the penetrator element of a TPDS is forged from stainless steel, the same stuff that was used as an armor piercing round in WWII, it has quite good armor penetration at ranges under 500 meters.