"Listed here in the chronology section of NICAP's 'UFO Evidence' report there's a pretty fascinating UFO encounter from over Jackson, Alabama on November 14th, 1956 where a pilot and co-pilot both witnessed a 'brilliant bluish-white light' perform highly unusual flight characteristics near their aircraft.
The UFO's maneuvers were said to last for 30 seconds and described as 'rising and falling, darting back and forth, instant 90° turns, then hovering motionless again' - when the control tower radioed the aircraft the object began another series of 'crazy gyrations, lazy 8's, square chandelles with undulating motion' and then shot out over the Gulf of Mexico in a steep climb at 'fantastic speed'.
What makes this case all the more interesting (or 'splendidly ironic' as it mentions in this
book) is the fact that the main witness pilot Captain W. J. Hull was a
published anti-UFO skeptic who had already written a 'debunking' article
in an Airline Pilot magazine three years before."...
"An 83-year-old Air Force pilot tasked with debunking alien sightings in the 1950s has revealed how he himself once saw a UFO."...
"Lt. Col. Richard French, a 29 1/2 year veteran of the US Air Force
describes an encounter where he came upon a down UFO that was underwater
and the beings who were working on the ship."