In this game you are tasked with filling the shoes of Hawkeye Pierce as Chief Surgeon of the 4077th...before he decided to believe a woman had killed a chicken on a bus.
In the first level you must pilot your helicopter in rescue operations of the wounded soldiers out in the field, while avoiding the trees, your fellow M.A.S.H surgeon in the other helicopter, and the North Korean tank at the bottom of the screen firing shells at you.
Once you've brought a soldier back to the camp, it's time to race against the clock and remove the shrapnel from the dying soldier, the controls seem to be a precursor to the Intellivision's Bomb Squad.
There is a third option with this game, a different helicopter game on a high difficulty level where you must rescue Colonel Potter's paratroopers. I don't remember Colonel Potter having paratroopers but its been some time since I've watched the television show so I could easily be in the wrong about this.
I might have to get an Atari Emulator and snag the ROM for M.A.S.H because it sounds like a pretty interesting title.