The exhaustive check of the laser module's five separate sections took longer than she had expected. Finally she reported back. "Payload monitor power off, Colonel. Check complete. Everything's in the green. Ready for launch."
"Control, this is Enterprise. Ready to resume countdown. Over," Sontag reported.
Colonel Will, with six years flying space shuttles, turned to the computer keyboard, punched in "SPEC 99 PRO" and the computer monitor on Sontag's side changed from a blank screen to a pictorial representation of the Enterprise's launch trajectory. Will checked the display. In case of a malfunction of all three of the general navigation computers, the GNCs, he would fly the Enterprise manually into orbit using the computer display as a road map. He keyed his microphone. "Control, this is Enterprise. Flight plan loaded and checked. Over. "
The checklists ran faster and faster. From T-minus twenty minutes to T-minus five minutes, Will and Sontag worked furiously. Their main job was to start the three auxiliary power units, the APUs, which supplied hydraulic power to Enterprise. During launch the APUs would make sure the Enterprise's aerodynamic surfaces were in their streamlined launch position; during landing or during an emergency the APUs would supply hydraulic power to the surfaces to allow the shuttle to be flown like a conventional airplane.
After T-minus five minutes Will and Sontag could do little but watch the computers on Enterprise and acknowledge status checks from Vandenburg Launch Control. "T-minus two minutes," Launch Control reported. "H-two and O-two tanks pressurized, Enterprise. You are go for launch. Over. "
"Copy, Control. We're go for launch. " Sontag looked over his shoulder once more at Page, Schultz and Baker. "Here we go…"
"Put the pedal to the metal, Colonel," Schultz said and immediately regretted it. Pretty callow staff, he told himself. The others indulged him by ignoring it. Ann settled herself as far as possible in her seat and pulled her seat straps tight as she could stand it. The air felt electric-not stuffy or humid but super-charged with power. Far below she could feel the rumble of another piece of equipment — the solid rocket booster's ignition APUs. The thought of six million pounds of thrust about to be let loose made her eyes shut tight. "T-minus ten seconds… nine… eight… "
She nearly jumped out of her seat as she felt a gentle touch on her left hand.
"Relax."
It'was Marty Schultz, nodding. "It'll be fine, relax." She took a deep breath, feeling as if it was the first she'd taken in hours.
…Six… five… four… ignition sequence start… main engine one ignition … two ignition… three ignition…" Sontag wasn't talking over the interphone — he was screaming out loud cross cockpit: "… Manifold pressure good all three engines… three in the green…"
One hundred feet behind Ann, the three main engines were cranking out one-and-a-quarter million pounds of thrust, but almost no noise or vibration could be felt. Ann did feel a twang, the sway of the orbiter towards the external tank as the main engines moved toward full thrust, but even that wasn't too noticeable.
She knew from endless simulation what came next. She could just make out the ABORT light on the front instrument panel. It hadn't come on, thank God. When the orbiter realigns itself after the twang it meant—
It felt as if a freight train had just rumbled out of nowhere right beside her — from near-quiet to ear-splitting sound — as the solid rocket boosters ignited. She couldn't help letting out a gasp as the solid rocket boosters, the SRBs, exploded into action. In three seconds the thrust beneath her had been multiplied by a factor of five; now the fury of over six million pounds of thrust was alive, and Enterprise had not yet even left earth.
Suddenly a huge hand pressed against her chest, causing her to involuntarily expel air in a grunt. Stars clouded her vision, but she could see the launch service tower drop from view.
Airborne. "Enterprise, you have cleared the tower. Engines look good." Ann was surprised to see Will and Sontag reaching up to their forward instrument panels; she tried to raise her hand against the "g"-forces, found they were light but building. Soon even lifting one hand took effort.
"Control, this is Enterprise. Main engines at sixty-five percent. Over."
"Roger, Enterprise. Standing by for max Q."
Ann clutched the armrests of her seat. Here came one of the most critical moments of the launch moment when all of the dynamic pressures affecting the shuttle were—
"Max Q, Control. Main engines one hundred percent."
"Roger, people. Very pretty launch. Spectacular. Out."
That was it? No earth-shaking rumble, no squashed face, no blasts of Vulcan heat? The "g" forces were noticeable, but Ann had felt worse lots of times…
"Coming up on SRB burnout, Control."
The solid rocket boosters burned out and were jettisoned precisely on schedule, under computer control. Enterprise was now several hundred miles west of Mexico on its southern pole-to-pole trajectory. The SRB motor casings, each floating to earth under dime one-hundred-fifteen-foot-diameter parachutes, would be retrieved over the Pacific Ocean.
Enterprise's ride was somewhat different from other shuttle flights. First, Enterprise was following an eccentric elliptical polar orbit instead of a circular equatorial orbit. And second, Enterprise was climbing to an altitude of one thousand miles so that it could rendezvous with Silver Tower as it traveled in high orbit. Because of fuel limitations, previous shuttle flights had been limited to a maximum altitude of about seven hundred miles above earth.
It was several hours before Will finally announced: "Welcome to space, crew. OMS burn is complete. We are in orbit." Relief washed across everyone's face. "We're within a few miles of Silver Tower's orbit," Sontag reported over interphone. "We saved ourselves a few hundred pounds of fuel on that burn, so we have a small safety margin. I'm estimating linkup with Silver Tower in two hour — it's about fifteen thousand miles ahead of us, but we're gaining… Marty, you're clear to open the cargo bay doors, After that you'll all be cleared to unstrap to begin system checkouts. Kevin, check the middeck for any damage or anything out of place."
Schultz and Baker acknowledged Sontag's call and began to unstrap. Ann looked on as Schultz's straps began to float around his vacated seat before he resecured them. "Remember," Schultz said, "even though you're weightless up here in orbit, your body still has mass that you need to overcome, which means stopping yourself after you get moving."
"So I noticed," Baker mumbled after he'd unstrapped and promptly collided head-first with the ceiling.
Schultz watched as Baker maneuvered himself around and floated out of sight down the ladder to the middeck level of the crew compartment. "Now to get those cargo bay doors," Schultz said. With Ann floating beside him, he made his way to the aft flight deck instrument panel. Ann looked out the windows facing into the cargo bay but it was too dark to make out any detail. "Panel R13 has the door controls," Schultz was saying. Over interphone he said, "Check power levels for cargo bay doors, Colonel Sontag."
Sontag checked the power distribution panel near his right elbow. "Switches set. " Next he checked a bank of three ammeters, switching the monitor controls through each of the fuel cells to check their output. "Power's on-line, Marty."
"Rog." To Ann, Schultz said, "Okay. Electrical power nins the hydraulic motors that operate the doors. There are also electrical backups, plus the doors can be opened and closed by the remote manipulator arms and even with an emergency space walk if necessary. The radiators deploy after the doors are fully open." Then over interphone Schultz reported: "Doors coming open."