Burt Lancaster plays a major during the Vietnam war when he was actually 65 years old and his age is impressed upon you in the first scene as he scrambles through the wire. His obvious age demands such a suspension of belief that it is difficult to focus on the movie. He makes a comment that he was once the General's commander so obviously got into trouble and was passed over for promotion in an attempt to "Explain away" the glaring visual age dysynchrony. But if he was a screwup at the rank of major he would have had his twenty years in and been discharged after being passed over for Lieutenant Colonel. I am sure the technical adviser pointed this out but hey they had Burt Lancaster starring. I was a major equivalent during the Vietnam War (US NAVY LCDR)and was 29 years old as were many of my peers + or - a couple of years so maybe it's not a problem with the non-military knowledgeable viewer.