Do I have permission to go?"

"All right. But listen: you've got one shot at the clamp, and whether it reaches or not you're coming straight out afterward. Understand? No one's ever been in a docking bay during flight before, and you're not equipped for unexpected problems."

"Gotcha. Here goes."Greenburg had spent the past couple of minutes studying the curving bay wall, planning just how he was going to do this maneuver. Now, as he shifted his weight and pushed off of Lewis's hands, he discovered he hadn't planned things quite well enough. Pushing himself more or less vertically through the narrow opening, he twisted his body around as his torso cleared, coming down in a sitting position with his back to the shuttle. But he'd forgotten about the oxygen tank on the back of his belt, and the extra weight was enough to ruin his precarious balance and to send him sliding gracelessly down the curving metal on his b.u.t.t.

He didn't slide far; Lewis, belaying the line, made sure of that. Getting his legs back around underneath him, Greenburg checked his footing and nodded back toward the opening. "Okay, I'm essentially down.

Let me have some slack." Moving carefully, he stepped down into the teardrop-shaped well under the shuttle and walked to the nosewheel.

The forward clamp was designed to slide out of the wall as the landing gear was lowered, locating the tow bar by means of two short-range transponders installed in the gear. Earlier, up on the flight deck, Greenburg had confirmed the clamp operation had been begun but not completed; now, on closer study, the problem looked like it might be obvious.

"The shuttle's not only angled into the bay wrong, but it's also rotated a few degrees on its axis," he reported to the others. "I think maybe that the clamp's wrist rotated as far as it could to try and match, and when it couldn't get lined up apparently decided to quit and wait for instructions."

"The telltales say it is fully extended, though," Henson insisted.

"Well... maybe it's the sensors that got scrambled."

"a.s.sume you're right," Betsy said. "Any way to fix it?"

"I don't know." Greenburg studied the clamp and landing gear, acutely aware of the vibrating shuttle above him*and of the vast distances beyond it. But even if the shuttle fell out and my rope broke I'd be all right, he told himself firmly. Standing in the cutout well that gave the shuttle's nosewheel room to descend, he was a good two meters below the rim of the bay's outer opening. There was a fair amount of eddy-generated wind turbulence plucking at his jumpsuit and adding a wind-chill to the frigid air*but it would take a lot of turbulence to force him up that slope and out. At least, he thought so.... "Why don't you try backing the clamp arm up and letting it take another run at the tow bar?"

"We'll have to wait for Peter's program to finish," Henson said. "The computer handles that."

"Oh... right." Greenburg hadn't thought of that. "How much longer?"

"It's almost*it's done," Whitney said.

"Where's the problem?" Betsy asked. Even with the turbofan engines droning in his ears Greenburg could hear the twin emotions of antic.i.p.ation and dread in her voice.

"There doesn't seem to be one."

"That's ridiculous," Greenburg said. "Something made the shuttle crash."

"Well, the program can't find it. Look, it seems to me I felt the Skyport bounce a little just before the crash*"

"Clear air turbulence," Betsy said. "That shouldn't have been a problem; the guidance program is supposed to be able to handle small perturbations like that.""Let's forget about the 'how' of it for now," a new voice broke in*Carl Young's, Greenburg tentatively identified it through the noise. "The point is that we can start bringing shuttles back up again.

Greenburg, is there anything you can suggest we bring up from the ground to secure the shuttle with?"

"Uh... h.e.l.l, I don't know. Something to use to get the pa.s.sengers off would certainly be handy. And if this clamp arm won't rotate any further we might need an interfacing of some kind*maybe an extra clamp-and-wrist piece to extend our clamp's rotational range."

"I've already ordered some spare ski lift track from the ground*it should be coming up aboard the first shuttle, along with men to handle it. The clamp-and-wrist section we may be able to remove from one of the other bays; other people will be coming up to try that. What I meant was, can you see anything from there that we didn't already know about?"

"Not really." Greenburg was starting to feel a little foolish as his brave descent into the bay began to look more and more unnecessary. With the guidance system coming up clean, shuttleloads of experts would be here in minutes. So much for the value of impulsive heroics, he thought acridly; but at least it hadn't wasted too much time. He'd always been much better as a team player, anyway. "Hold on tight, Tom; I'm coming up," he called, getting a grip on his safety line.

"Just a second, Aaron," Henson said. "I've got the computer back now. Why don't you stay put while I try the clamp again like you suggested."

"All right. But make it snappy*it's freezing in here."

There was a heavy click, and the clamp arm telescoped smoothly back into itself, rotating to the horizontal as it did so. It paused for a second when fully retracted and then reversed direction, angling toward the landing gear like some rigid metallic snake attacking its prey in slow motion. It stopped, again a meter short, and with a sinking feeling Greenburg saw his mistake. "It's not just the angle the nosewheel's at," he informed the others. "The clamp rotates a little as each segment telescopes out, not all at once at the end of the extension. It's not quitting because it doesn't know how to proceed*it's quitting because it's run out of length."

"That's impossible," Betsy retorted. "I've checked the stats*the arm's got to be long enough to reach."

"Then it's been damaged somehow," Greenburg said irritably. If they had to replace the whole arm, and not just the clamp... He shivered as a newly sharpened sense of the shuttle's vulnerability hit him like a wet rag.

For a moment the drone of the turbofans was all he could hear. Then Carl Young said, "We'll have the ground people check it out when they get here. Greenburg, you might as well come out of there. You'll need to put the access panel back in place temporarily so we can repressurize the deck."

"Understood." Turning back to the curving wall, his hands numb with cold, Greenburg began to climb.

"The shuttle will dock in Six in about four minutes," the Skyport captain's voice came over the intercom.

"Okay, Carl," Betsy said. "Six, do you have someone at the bay to meet it?"

"Not yet," was the response. "We wanted to have all the stations up here manned during docking, to watch for any trouble. We could call in somebody off-duty, if you want.""Don't bother," Paul Marinos said, unbuckling his seat belt and getting to his feet. "I'll go down and meet the shuttle. You won't need me before Tom gets back, will you?" he added looking at Betsy.

She shook her head. "Go ahead. As a matter of fact, you can probably escort Mr. Whitney back down on your way. Mr. Whitney, we very much appreciate your help here this morning."

"Uh, yeah. You're welcome."

Unlocking her chair, Betsy swiveled around. Whitney was hunched forward in his own seat, frowning intently at the computer display screen. "Anything wrong?" she asked, her mouth beginning to feel dry again. That shuttle would be trying to dock in a half-handful of minutes....

Whitney shook his head slowly, his eyes never leaving the screen. "I'm just rechecking the readout, trying to see if there's anything that looks funny but somehow didn't register as a problem." He keyed for the next page; only then did he look up. "If it's not too much trouble, though, I'd really like to stay up here for a while. I can be an extra hand with the computer, and there's another project I want to discuss with you."

"Pa.s.sengers usually aren't permitted up here at all," Marinos said with a frown.

Whitney shrugged. "On the other hand, I am already here."

"All right," Betsy said, making a quick decision. Even if Whitney's primary motivation was nothing more than simple curiosity, he'd already been a big help to them. It was an inexpensive way to pay back the favor. "But you'll have to stay out from underfoot. For starters*" she pointed at the display*"you'll need to finish that up quickly, because Tom Lewis's on his way up to make some more blueprints."

"Yes, I know. I'll be finished." He turned back to the console. Nodding to her, Marinos left the flight deck.

Swiveling back forward, Betsy squeezed her eyes shut briefly and took a long, deep breath. The tension was beginning to get to her. She could feel her strength of will slowly leaking away; could feel her decision-making center seizing up*and this only some eighty minutes into the crisis.

The strength of her reaction was more than a little disturbing. True, the lives of a hundred-sixty people were hanging precariously in the balance back there... but she'd been holding people's lives in her hands since her first flight for the Navy back in 1980. She'd had her share of crises, too, probably the worst of them being the 747 that had lost power in all four engines halfway from Seattle to Honolulu. She'd had to put the monster into a five-thousand-foot dive to get the balky turbofans restarted*and she hadn't felt anything like the nervousness she was feeling now. Was it just the length of this crisis that was getting to her, the pumping of adrenaline for more than five minutes at a time? If so, she was going to be a wreck by the time this whole thing was resolved. OrOr was it the people*be honest, Betsy; the person*involved? Could being forced to deal with Eric Rayburn again really hit her this hard? "Excuse me, Captain; is it all right if I sit here?" She opened her eyes to see Whitney standing beside her, indicating the copilot's seat. Craning her neck, she saw that Lewis had returned and had taken over the computer terminal again. "Yeah, sure," she told Whitney, thankful for the interruption. "Just don't touch anything. Tom, you need any help?"

"No, thanks; just getting the schematics for the clamp arm mechanism, the emergency collar, and whatever I can find on the Skyport door and tunnel." Paper was beginning to come from the printer slot; Lewis glanced at it and then looked at Betsy. "Anything new from the shuttle?""Rayburn's still checking out his instruments. So far the altimeter, Collins nav system, and at least one of the vertical gyros seem to be out; the compa.s.s and collisionproofing are intact; the autopilot is a big question mark."

"I met Paul Marinos on the way up here. He said it was Rayburn who came up with that half-a.s.sed idea of letting the shuttle fly home alone."

"That's right," Betsy confirmed. "He's still making noises in that direction, too."

"Good. Aaron and I thought you'd thought it up, and we were getting a little worried."

She snorted. "Thanks for your confidence. You staying with Aaron after you deliver the schematics?"

"Depends on whether they need me or not," he said, pulling the last sheet from the printer slot and flipping the "off" switch. "Talk to you later."

He got up and left, and as he did so the intercom crackled. "This is Marinos. The shuttle has docked.

Textbook smooth, I might add."

Betsy turned to the intercom grille, feeling a minor bit of the weight lift from her shoulders. "Aaron, you copy that? Prepare for company down there."

"Got it. Paul, let me know when you're all down, so I can start taking this panel off again."

"Will do."

The intercom fell silent, and Betsy leaned back in her seat again. Staring out the window at the blue sky, she tried to organize her thoughts.

"Captain? Are you all right?"

She glanced at Whitney, favoring him with a half smile. "I thought I told you we all went informal up here," she chided mildly. "My name's Betsy."

"Oh... well... you called me 'Mr. Whitney' a while back, so I thought maybe that had changed." He looked a little embarra.s.sed.

"Force of habit, I guess. Anyone wearing a three-piece suit looks like management to me. And as to your question, yes, I'm fine."

"You look tired. How long have you been flying?"

A chuckle made it halfway up her throat. "About twenty-six years, all told. This session, though, less than an hour and a half. I came on duty just before the shuttle crashed."

"Oh." His tone said he wasn't thoroughly convinced.

She looked at him again. "Really," she insisted. "What you're calling tiredness is just tension, pure and simple."

The corner of his mouth quirked. "Okay. I always was a lousy detective." The quirk vanished and he sobered. "What do you think their chances are? Honestly."

"It all depends on how fast we can get the shuttle secured*or how fast we find out we can't do it."Whitney frowned. "I don't follow. Are you talking about the*" he glanced at his watch*"six hours of fuel the shuttle's got left?"

"Basically*except that it's only about five and a half now; we nudged his thrust up a notch in two of his engines a while ago." She turned to face forward again, lips compressing into a thin line. "We're in a very neat box here, Peter. You know the Skyport clockwise circuit, don't you?"

"Sure: Boston, New York, Philadelphia, Washington, Atlanta, New Orleans, Houston, Dallas, L.A., San Francisco, Denver, Kansas City, Chicago, Detroit, Cleveland, Pittsburgh, Washington, then back up the pike to Boston." He rattled off the names easily, as someone who'd learned them without deliberate effort. "A twelve-hour run, all told."

"Right. Now note that once we secure the shuttle, there are exactly two places we can land with it: the Skyport maintenance facilities at Mirage Lake, near L.A., and the Keansburg Extension of New Jersey; and L.A.'s probably a half hour closer. But*" she paused for emphasis*"between here and L.A. there are no Skyport cities. Which means no shuttles. Which means any equipment we want to bring aboard to work with has to come from here. Which means we have to stay here until we're sure we've got everything we're going to need."

"Wumph." Whitney's breath came out in a rush, and for a moment he was silent. "But couldn't you head toward L.A. right away, circling there until you have the clamp fixed? Oh, never mind; you'll probably need the transit time to work. But wait a second*you could head back east now, toward New Jersey. Any extra stuff you needed could be brought up from Atlanta, or even Washington; you'd pa.s.s close enough to both cities on the way."

She'd had the same brilliant idea nearly twenty minutes ago, and had been just as excited by it as he was.

It was a shame to have to pop his bubble. "The fly in that particular soup in John Meredith, the injured shuttle copilot. If we stay here and then manage to get him and the other pa.s.sengers out within an hour, say, we can get him to a hospital a lot faster than if we had to wait till we reached Atlanta. That time could be life or death for him*and it's the uncertain nature of his injuries, by the way, that gives our box its other walls. Besides," she added grimly, "if we wind up losing the shuttle completely, I'd rather try and find an empty spot in Arizona than in Pennsylvania to drop it into."

"d.a.m.n," he muttered. "You've thought through the whole thing, haven't you?"

"I hope not," she countered fervently. "Things don't look too good in my a.n.a.lysis. If I haven't missed something we're probably going to lose either an expensive shuttle or at least one irreplaceable life." She snorted. "d.a.m.n the FAA, anyway. We've been on their tail for at least two years now to push for a few more wing section-sized runways scattered among the major airports."

"Yeah, I've always thought it was a bad idea to leave thrust reversers off Skyport engines. The way things are now, you could lift a module off from a ridiculous number of runways that you couldn't put it down on in the first place."

"It's called economy. No one wants to build extra-big runways until they're sure the Skyports are going to catch on." She shook her head. "Enough self-pity. What's this project you mentioned?"

"Right. You said earlier that no one knew what sort of landing distance a wing section-shuttle combo would require. Well, I've done some figuring, and if I can use the combined computer facilities of two modules I think I can get you a rough estimate."

She blinked in surprise. "How?""My work for McDonnell Douglas has been on computer simulations for second-generation Skyport design. Most of it involves adjusting profile, ma.s.s, and laminar flow parameters and then testing for lift and drag and so on. I remember the equations I'd need and enough about module and shuttle shapes to get by. And it's not that complicated a program."

"What about the brakes and drogue chutes?" she asked doubtfully.

"I can put them in as extra drag effects."

Betsy frowned, thinking. There was no way the runways at Dallas would be long enough*of that she was certain. But... the figures would be nice to have. "Okay, if we can get two of the other wing sections to agree. You can't use Seven's computer; we'll need to leave it clear for the work down below."

"That's okay*I can link to the other systems and run everything from here."

Betsy turned toward the intercom. "Carl? What do you think?"

"It's worth trying. Two, Three*you've just volunteered your computers to Mr. Whitney's use."

It took Betsy a few minutes to show Whitney how to set up the two-system link, but once he got started he did seem to know what he was doing. She watched over his shoulder for a minute before returning to her seat. It was indeed a good idea, but she had to wonder why he hadn't simply called back his friend in Houston and had him run the program. With the*undoubtedly*larger machine there and the proper program already in place, they could surely have had the answer faster than Whitney could get it here. It was looking very much like he did indeed want an excuse to stay on the flight deck and observe the proceedings. She grimaced. The report he was presumably going to be making to McDonnell Douglas wasn't likely to be a flattering one.

She shook her head to clear away the cobwebs. There were plenty of unpleasant thoughts to occupy her; she didn't need to generate any extra ones. And, speaking of unpleasantries... Steeling herself, she pulled her half-headset mike to her lips and switched it on. "Skyport to Shuttle. Status report, please."

"Oh, there's nothing much new here, Liz*just sitting around watching my copilot dying."

She'd been unprepared for the sheer virulence of Rayburn's tone, and the words. .h.i.t her with almost physical force. Unclenching her jaw with a conscious effort, she asked, "Is he getting worse? Dr.

Emerson?"

"He sure as h.e.l.l isn't getting any better," Rayburn snapped before the doctor could answer.

Betsy held her ground. "Doctor?" she repeated.

"It's hard to tell," Dr. Emerson spoke up hesitantly. "He's still unconscious and his breathing is starting to become labored, but his pulse is still good."

"Well, we should at least have him out from under all that metal soon," Betsy told him. "The ground crew's aboard now, and they'll be bringing a torch aboard to cut the chair free."

"Yeah, I can see them climbing in down there," Rayburn said. "How do they expect to get up here?"

"Through your side window; I presume they brought a rope ladder or something with them. You'd better open up and be ready to catch the end when they toss it up.""h.e.l.l of a lot of good it's going to do," the shuttle pilot growled. "How're they going to get him back out*tie a rope around him and lower him like a sack of gra.s.s seed?"

"If he's not too badly injured, yes," Betsy said, feeling her patience beginning to bend dangerously. "If not, we'll figure out something else. We're going to try and rig up a ski lift track from your window to the Skyport door to get the pa.s.sengers out; maybe we can bring Meredith out that way on some kind of stretcher."

"A ski lift track? Oh, for*Liz, that's the dumbest idea I've ever heard. It could take hours to put something like that together!"

The tension that had been building up again within Betsy suddenly broke free. "You have a better idea, spit it out!" she barked.

"You've already heard it," he snapped back. "Let me take this d.a.m.n bird down now, and to h.e.l.l with ski tracks and nosewheel clamps. All you're doing is wasting time."

"You really think you can fly a plane with its nose smashed in, do you?" she said acidly. "What're you going to use for altimeter, autopilot, and gyros?"

"Skill. I've flown planes in worse shape than this one."