How does a.................

shoot&scoot

Thanks, that's more than I knew before!  That last bit about using the boom from a wrecker to push the gun tube back might make a neat dio!  Hmm.................................

                                                                             Pat.

True, but the layman will have no idea what's going on or why when he views it.

Thanks, that's more than I knew before!  That last bit about using the boom from a wrecker to push the gun tube back might make a neat dio!  Hmm.................................

                                                                             Pat.

I really don't know a lot about it, just the basic principle of its operation. The only maintenance the crew does to the system is to check the level, making sure it is at the MIN LEVEL as seen in the photo, and at least annually or prior to gunnery Direct Support maintenance does a "pullover" check.

What they do is use the boom of a wrecker to push the gun tube through a recoil cycle and check for leaks and such. The boom of a military wrecker extends out. Something is inserted into the end of the barrel (to prevent metal on metal damage between the boom and gun tube). The the boom is extended to push the gun tube into recoil. The turret rats are inside doing their checks of the recoil system.

Thanks Rob!  I was asking about the recuperator on the main gun.  Your answer cleared up one question but raised a few others.  What type of mechanism is in the chamber that's halfway down the gun to pressurize the FRH ( diaphragm or piston) and how is the FRH returned to the rear of the gun (external hoses or internal passages)?  Also, what type of maintenace is required on this system?

Thanks again for putting up with an armor illiterate.

                                                                                            Pat.

Which recurperator? There are two on an Abrams and both do very different jobs. The one on the main gun contains FRH (flame resistant hydraulic) fluid and works much like a shock absorber. As the main gun recoils, pressure pushes the fluid into a reservoir attached to the turret above the main gun. There are oneway valves to ensure the fluid flows in one direction. Once the gun reaches full recoil and ejects the spent cartridge, the pressurized fluid continues to flow out of the reservoir and push the gun back into battery.

Here is a photo of the reservoir over the main gun.

After a few firings, the fluid gets rather hot (like a car's anti-freeze tank). If one of those hoses fails and gets a pin *** sized hole, steaming hot FRH sprays out and you get a scene similar to those submarine movies with water pouring in through pipes. The gunner gets it worst and the crew smells like oil for a while.

The other recuperator has to do with the turbine engine. It uses exhaust heat to preheats the air so it doesn't use as much fuel to get fuel-air mixture to burn efficiently. It's one of the reasons an Abrams has to cool down for a minute or two prior to shutting down the engine, so the recuperator has a chance to cooldown at a steady rate and lessen the chance of it warping.