The voice of Mission Control spoke over the loudspeakers and into hundreds of headsets.
THE GROUND LAUNCH SEQUENCER HAS BEEN INITIATED. WE'RE AT T-MINUS 120 SECONDS AND COUNTING.
The Space Shuttle Columbia was on Launch Pad 3, in its final preparation for another secret mission. As was expected, the Department of Defense issued a terse non-statement on its pur- pose: "The Columbia is carrying a classified payload will be used for a series of experiments. The flight is scheduled to last three days."
In reality, and most everyone knew it, the Columbia was going to release another KH-5 spy satellite. The KH-5 series was able, from an altitude of 110 miles, to discern and transmit to Earth photos so crisp, it could resolve the numbers on an automobile license plate. The photographic resolution of KH-5's was the envy of every government on the planet, and was one of the most closely guarded secrets that everyone knew about.
T-MINUS 110 SECONDS AND COUNTING.
Mission control specialists at the Cape and in Houston monitored every conceivable instrument on the Shuttle itself and on the ground equipment that made space flight possible.
A cavernous room full of technicians checked and double checked and triple checked fuel, temperature, guidance, computers sys- tems, backup systems, relays, switches, communications links, telemetry, gyros, the astronauts' physiology, life support systems, power supplies . . .everything had a remote control monitor.
"The liquid hydrogen replenish has been terminated, LSU pressuri- zation to flight level now under way. Vehicle is now isolated from ground loading equipment."
@COMPUTER T-MINUS 100 SECONDS AND COUNTING
"SRB and external tank safety devices have been armed. Inhibit remains in place until T-Minus 10 seconds when the range safety destruct system is activated."