QF-4E PhantomQF 4E drone airplane model. The F 4E Phantom is essentially an F 4D with improved J79 GE 17 engines (900 lbs. more static sea level thrust each) and a M61A1 "Vulcan" 20mm cannon. Operational experience gained in Vietnam had a direct influence on the addition of the cannon. The air to air missile fire to hit ratios were low and air combat usually degenerated to subsonic 'dogfighting' where the F 4 was at a decided disadvantage when flying against more