Goodbye, Farewell, and Amen - S11-E16
Revealing mistake: Col. Potter is taking Sophie to the orphanage at the end of the show. "Sophie" is a male horse. Look closely.
Goodbye, Farewell, and Amen - S11-E16
Continuity mistake: While everyone's gathered for their last evening together, taking turns telling what their life will be like when they get home, there are three closeups of Kellye in which we see that her caduceus insignia pin is on her right lapel and her First Lieutenant bar is on her left lapel, though it should be the opposite way, and her closeups are not flipped. The pins are on the proper side in other shots of Kellye during the episode.
Goodbye, Farewell, and Amen - S11-E16
Continuity mistake: When Father Mulcahy releases the locked up POWs, in the following explosion Father Mulcahy is knocked to the ground and his eyeglasses are still on his face properly, but in the next shot when BJ rushes to his side the eyeglasses are on the ground behind Mulcahy's head, and BJ did not remove them.
Goodbye, Farewell, and Amen - S11-E16
Continuity mistake: When Hawkeye is returning to camp, he and his driver completely pass some Burma-Shave signs the other have set up to welcome him back. An ambulance bus is a few feet behind them and manages to then suddenly appear at least 30 feet behind them to smash all the signs.
Goodbye, Farewell, and Amen - S11-E16
Deliberate mistake: BJ mentions to Charles that if they don't sign the armistice it will be the second time in 2 years and then he will miss his daughter Erin's second birthday. This is BJs 7th season and when he arrived at the beginning of season 4, Erin was already born, making it absurd that seven years later she could still be one year old. Because the real war lasted 3 years and the show 11, there are obviously some errors like this that can't be avoided but this was blatantly egregious.
Goodbye, Farewell, and Amen - S11-E16
Other mistake: When Hawkeye drives the damaged tank out of the camp, the front MG is missing. There's not a mark on the armor surrounding the MG port that might suggest it was destroyed in battle. Why would a tank in combat just be missing one of its MGs?
Goodbye, Farewell, and Amen - S11-E16
Factual error: When Hawkeye leaves the tank after parking it in the trash heap, he comes out of the cupola hatch. He should be coming out of the driver's hatch, because he sure as hell didn't drive that tank from the turret.