Mullane recalled that while filming the reentry through the upper deck's overhead windows, "I had visions of molten aluminum being smeared backwards, like rain on a windshield". Although the shuttle landed safely "The damage was much worse than any of us had expected", he wrote. Upon landing, the magnitude of the damage to the shuttle astonished NASA; over 700 damaged tiles were noted, and one tile was missing altogether. The missing tile had been located over the aluminum mounting plate for an L-band antenna (one of six, part of the TACAN landing system), perhaps preventing a burn-through of the sort that would ultimately doom "Columbia" in 2003. There was almost no damage present on the orbiter's left side. STS-27R "Atlantis" was the most damaged launch-entry vehicle to return to Earth successfully. Gibson believed that had the shuttle been destroyed, Congress would have ended the shuttle program given that only one successful mission had occurred between his flight and the loss of "Challenger".