Factual error: Sergeant Major Dickerson wears his blue infantry cord on his left shoulder. The cord is correctly worn on the right.
Factual error: The movie is set in Saigon, 1965. Adrian Cronauer plays "What a Wonderful World" by Louis B. Armstrong on his radio show, but the song wasn't recorded until August 16, 1967.
Factual error: The movie is set in 1965. In a Saigon street scene, a Volkswagen of later vintage can be seen driving by. (The larger taillights are the give-away.).
Factual error: All through the movie Pfc. Garlick is shown trying to turn the key on a jeep that is already running. The reason that this is a mistake is that tactical vehicles (jeeps) do not have ignition keys they have a starter button. So if you want to keep someone from stealing your jeep you padlock the steering wheel.
Factual error: The movie is set in the mid-sixties. During one of Adrian's manic on-air riffs, he repeats "redrum, redrum", obviously borrowed from "The Shining", the book and film of which were released well after the end of the Vietnam War.
Factual error: In the restaurant after being suspended, Cronauer is seen singing "You Keep Me Hangin' On" by the Supremes. The movie is set in 1965, but the song was not released until 1966.
Factual error: Garlick's eyeglasses would most likely be out of regulation since they are wire framed. Despite him serving in a non-combat role in Vietnam, he should most likely be wearing Gray Cellulose framed ones (commonly called BCGs or Birth Control Glasses).
Factual error: After talking to the troops in the trucks, when the trucks start back up, the noise is a 1980's version of the deuce and a half with a turbo-charger.The trucks in 1965 should have gasoline engines. Most M35s didn't get diesel engines until 1970.
Factual error: The jeep they are driving into the jungle that gets blown off the road is actually a civilian jeep, as evidenced by the headlight trim rings being mounted on the outside of the grill. Military jeeps have the lights behind the grill to facilitate "blackout" lighting.