The two Korean War-era helicopters seen are two Sikorskys- the H-5 and the H-19 Chickasaw. Both were workhorses for battlefield rescue of downed pilots and wounded soldiers.
This film was showing on the screen as photographer O. Winston Link snapped his iconic photo of a Norfolk and Western freight train passing an Iarger, West Virginia drive-in theater, titled "NW1103 Hot Shot Eastbound". According Smithsonian Magazine: "The explosion of light washed out what was on the movie screen at the moment; he had to print the image of the plane from a negative he'd made separately of that night's showing."