An interesting scenario - concussion
 

I was recently reading in a book about Cobra gunships in Vietnam. One crew was trying to stop a PT-76, but had no weapons that could penetrate the PT-76's armor. They decided to try to make it turn tail by hammering it with HE rockets, and their fire was very accurate.

Then the PT-76 just coasted to a stop. When the infantry guys got to it and got the hatches open, the crew was dead, but the PT-76 was essentially undamaged. The concussion from the HE rockets had gone through the armor and killed the crew.

Can anyone think of a rule for that?

I've read about that incident too Paul. I think they were using smoke or market rockets rather than HE. After all the PT-76 was make with ALOT of aluminuim which is pretty easy to penetrate.

As for that, concusion probably covers it, and an effect of the shockwave. Remember the stories of B-52 strikes and they would kill people from the concusion alone, they would be untouched in their bunkers but their brains and other systems would be scrambled from the concusion, or the shockwave that would suck all of the air out of thier lungs and again the concusion would basicaly destroy the lungs too. <remember firing a heavy weapons system and feeling the rumble or concusion in the chest? Now multiple it times ALOT! It would mess you up.>

I' ve read that, during World War II, it was a common event that a tank, having received an impact from a round unable to penetrate its armour, remained inactive in the field of battle for a while or indefinitely. All the kinetic energy from the impacting round was absorbed instantly by the part of armor affected, that transmits this energy as a massive shock wave to all the tank. The entire vehicle can act as a big resonance box (not sure if this a correct English term):confused: .
The result could be simply a confused crew their ears aching. But other effects like the loss of consciousness or dead were possible, depending of the proximity of the crew member to the impact zone.

A RPG from Spain called "Comandos de guerra", has a special rule covering this. Basically, if the vehicle suffers the loss of armor points due to the impact of a round, the crew must make a constitution roll to avoid loss consciousness, with a catastrophic failure involving death. The difficulty of the check was adjusted by the proximity to the impact zone.

In T2K (v2.2) the crew members can suffer damage either with a "minor" or with a "major damage" result on the Vehicle Damage Table. And the rules take in to account the position of the crew member. So perhaps the only adjustment necessary may be the CON check of the all the crew members, DIFFICULT for those who has suffered damage in the Vehicle Damage Table and AVERAGE for the others. With a failure, apply 1d6 damage points to the head. Catastrophic failure doubles damage. Perhaps a good option would be to limit this effect only to large caliber guns.

Interesting scenario. I'd never heard that one about the PT-76.

I think armor type and thickness would be an important factor in determining damage to crew from concussion.

I've read dozens of accounts from German and Soviet tank crewman in WWII describing having received mutliple AT hits and continuing to fight the tank with minimal interuption to combat operations from crew injury. These were Panther/Tiger and T-34 crewmen though, so we're talking tanks with pretty darn good armor protection for the time.

Lots of "panic" rolls for the crew each time the tank is hit. Eventually they will panic and have to leave the vehicle, at which point they will be hit by HE/concusion.

Maybe not quite what your after, but the outcome is almost the same (vehicle not damaged but crew dead).

I've heard that story about the Cobra and the PT-76 also. i wonder why they didn't try the 40-mm grenade launcher alongside the minigun-they should've knocked off a tread, or gone through the top armor on the turret and engine deck.

Early models of the Cobra didn't always have the GL -- a lot of combinations were tried before they settled into a standard configuration.