''Cactus 564'' was a routine America West flight that began in Tampa, Florida. The final leg of the flight was from Dallas/Forth Worth into Las Vegas, the ultimate destination.
On the night of May 25, 1995, Flight 564, a Boeing 757 piloted by Captain Eugene Tollefson and First Officer John J. Waller, was passing near Bovina, Texas, just across the state line from Clovis, New Mexico at about 9:25 MST. There were thunderstorms to the northeast, and the lead flight attendant was watching the lightning flashes in the night sky.
This flight attendant was the first to notice a line of regularly flashing lights in the sky to the north and below the airliner. The First Officer then saw them as well, and they observed a horizontal row of eight strobe-like lights, flashing on and off in sequence from left to right.
The lights, which were as bright as aircraft landing lights, were at an altitude of between 30,000 and 35,000 feet, and were bright white with a tinge of blue.
Captain Tollefson left his seat to look, and he saw the left to right sequencing lights also. As the lightning flashed behind the lights, it silhouetted something that to the observers appeared to be a large, dark, cigar shaped object between 300 and 500 feet in length, depending on how far away it was.
After about five minutes of observing the object, Flight 564 called Albuquerque Air Traffic Control to report the object. Albuquerque ATC noted that the position of the object was over a restricted military area called ''Tieband.'' The controller also noted that the description sounded similar to that of a tethered aerostat except for the large number of strobes. However, the controller contacted sites that would know if an aerostat or any other military aircraft were in the air that night, and was given negative responses all around. The controller contacted other aircraft in the area, but no one else was able to see what Flight 564 saw.
The controller then contacted NORAD, who at first reported nothing on their radar at that location, then called back and said they had an unidentified return in that area, then called back again and said that the radar return had been a common small airplane with a malfunctioning transponder. An air traffic controller later said that there was yet another call from NORAD reporting that they later did have an unknown at that precise location, but this has never been corroborated. There is a transcript of the controller's radio conversations at UFO Plaza and there is a Real Audio excerpt of the conversations from the ''Sightings'' TV program at Cosmic Videos
No satisfactory explanation has ever been found for the Flight 564 sighting
Source: Loy Lawhon, About.com