[Divine-wind]

According to a quick Wikipedia search your UFO looks like a T-28:

The North American Aviation T-28 Trojan was a piston-engined military trainer aircraft used by the United States Air Force and United States Navy beginning in the 1950s. Besides its use as a trainer, the T-28 was successfully employed as a Counter-insurgency (COIN) aircraft primarily in Vietnam.

The canopy and tail, as does the general profile.