Goofs

When Stock and the rest of his platoon reach the top of the mountain, the lower part of the left sleeve on his shirt has been cut away. It remains like this for the rest of the film and isn't explained until the last battle. Stock has a wound on his arm and a bandage has been applied, but no wound was visible until after the final battle.

When Merrill and Stockton converse after the first battle, Merrill's pipe moves instantaneously to and from his mouth between shots.

When the troops are resting in the swamps, mud patches on Bullseye's arms appear and disappear between shots.

When Merrill is writing his letter at the railhead, the closeup shows his writing is well up in the top third of the paper, but in the wider shot he is seen writing under the middle of the page.

The role played by the Chinese Nationalist Army in the campaign is completely absent. In reality, troops from the 42nd and 150th Chinese Infantry Regiments of the X Force were a major part of the fighting; indeed the final victory at Myitkyina was only possible after Chinese reinforcements were flown in.

The role of Japanese-American translators who served with the 5307th is also ignored.

The British officer incorrectly had his slouch hat pinned up on the right side. Commonwealth troops have always worn the slouch hat pinned up on the left side to accommodate left shoulder (sloped) arms.

Many of the men can be seen wearing their watches with the face on top of the wrist. They would actually have been on the underside to prevent reflection of the sun giving them away.

When Claude Akins is interacting with the soldiers who are eating their chow, he constantly has his finger on the trigger of his Thompson sub-machine gun, a safety violation in the field.

When the attack on the rail yard starts, a GI is shot as he crosses the rails. He falls down, and then, after he is down, he raises his arm up and drapes it across the rail.

General Stilwell tells Merrill that he is concerned about the Japanese linking up with the Germans in India. This was a fear in 1942, when the Germans had conquered a vast expanse of Soviet territory, and it looked like they would reach the Caspian Sea and then Persia. But the German advance was turned back at Stalingrad in February 1943. At the time of the conversation in the movie, in early 1944, the Germans were being pushed out of Ukraine. They had no chance of linking up with the Japanese any more.

When they reach the railroad and airdrops are scheduled, Will Hutchins' character watches the airplanes making the drops. The aircraft are Douglas C-124s which didn't enter service until 1950 - for the 1944 era of the movie, the aircraft would have been Douglas C-47 or Curtiss C-46 airplanes.