Hey! Today I was flying a the SOFIA at 45,000 ft from Palmdale to Palmdale.
The 747-SOFIA better known as the 747-100 or 747SP was and still is used by NASA for Stratospheric Observatory for Infrared Astronomy. This particular 747-SOFIA was a United 747SP before being given to NASA for research.
Route: KPMD-KPMD (Palmdale, California)
Flight Information: Alt: 45,000 ft, Spd: M0.88, Flight Time: 2 hr flight time