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  ‘I’ll do the passenger briefing.’ Hartigan’s voice interrupted her thoughts, and Clare nodded. It would give her a little more time to get herself ready for the descent.

  Hartigan turned slightly in his seat so that he could look back to the passengers behind him in the spaceplane’s cramped cabin. They were all wearing the same bright orange crew escape suits that he and Clare had on for the descent, and they looked back at him through their open helmet faceplates.

  He flicked a switch, and his voice came over the intercom: ‘Okay guys, Lieutenant Foster’s making the final preparations now for our descent. We’ve a few minutes to go before we fire the engines for the re-entry burn, so I’ll just remind you what’s going to be happening, before it gets busy up here.

  ‘The re-entry burn takes just over three minutes, and that will slow us down so that we start coming down from our present orbit. Right after the burn, we’re going to turn the ship over so that we face forwards for re-entry, rather than backwards as we are now. Shortly after that we’ll make our contact with the atmosphere, and then it’s a few minutes of re-entry before we’re flying in the atmosphere. We should be landing in about thirty-five minutes from now. Any questions, or concerns?’

  The passengers all shook their heads. Hartigan waited for a moment to be sure, but he knew from the passenger list that they had all done this before.

  ‘Okay, let’s have those faceplates down and locked, and make sure your seat straps are tight; the latest high-level weather report suggests that it might be a little bumpy on the way down.’

  He flipped the intercom switch back and spoke to Clare. ‘Ready for the descent checklist?’

  ‘Sure.’

  Hartigan leaned forward and punched up the checklist items on one of the lower displays. ‘Nosecone.’

  ‘Up and locked.’

  ‘Visor.’

  ‘Up.’

  ‘Air supply.’

  ‘Both packs on automatic.’

  ‘Autopilot mode.’

  ‘Re-entry set and – armed.’ Clare pressed a button on the glareshield panel in the centre of the instrument panel. Both of them knew the checklist items by heart for every phase of the spaceplane’s flight, but the drill of checking against the list was ingrained just as deeply.

  She didn’t miss anything, Hartigan thought as they finished the list. He believed in keeping quiet if everything was going well, and he sat back and watched her careful efficiency as she turned the spaceplane slightly to better align it for the re-entry burn. His gaze flicked briefly to her face, and the narrow line of her jaw. She was pretty in an unremarkable way, sitting tall in her flight seat, her ash blond hair tied back from her face in the bulky helmet.

  If she’s nervous, he thought, she isn’t showing it. But that was typical of her approach to new challenges. Hartigan had been her commanding officer for the last year of her training, and had overseen much of it himself. For a twenty-four-year-old second lieutenant in the Astronautics Corps she was making excellent progress; she had been earmarked for rapid promotion if she continued to make the grade.

  As if aware of the scrutiny, she turned her head and her dark blue eyes looked back at him.

  ‘Ready for descent.’

  As if on cue, the spaceplane’s flight computer spoke for the first time:

  ‘De-orbit burn in sixty seconds. Decide now.’

  ‘Proceed. Take us down.’

  ‘Yes sir.’ She pressed the glowing ARM button on the engine control panel, locking in the ignition sequence to the autopilot. Far behind them, she heard valves opening, and faint creaks came through the spaceplane’s structure as the propellant tanks pressurised.

  Clare lowered and locked her helmet faceplate and pulled her seat straps tight over her shoulders. From the corner of her vision, she could see Hartigan doing the same. His hand reached out to rest on the autopilot disconnect button on his sidestick, which would cancel the ignition sequence if it was pressed before the engines ignited. Once the engines had started their predetermined burn, it took two separate actions to stop them, as a safety precaution against accidental shutdown.

  From here on in, the ignition and de-orbit burn were automatic. The flight computer continuously calculated their position and velocity until the precise moment when the engines needed to fire to reduce their orbital speed and start them on the fiery road down to the planet. Clare just had to monitor the sequence, making sure that the ship followed both the computer-generated flight plan and the independent calculations that she and Hartigan had made before they boarded, as a safety check. They were there in front of her, written on an index card clipped to the instrument console. If she had to take full manual control for any reason, those scribbled numbers would enable her to steer the ship safely through the re-entry corridor and somewhere near to their target.

  ‘Main engine ignition in ten seconds.’

  Hartigan thumbed the intercom to warn the passengers. ‘Firing main engines in – six seconds.’

  A distant whine came through the structure of the spaceplane as the turbopumps spooled up, forcing fuel and liquid oxygen into the combustion chambers. Clare leaned back in her seat, and a moment later the four engines fired with a deep rumble, shoving them back into their seats with the deceleration from two million newtons of thrust.

  ‘Ignition okay, four good engines,’ Clare reported, watching the engine situation display. Thrust was even, chamber pressures were stable, and the propellant flow was steady at thirty-three tonnes a minute of ultra-cold liquid propane and liquid oxygen.

  The navigation displays changed to show the spaceplane’s declining velocity against the downward magenta curve of its planned flight path. The engines were firing against the direction of their path, slowing the ship down and allowing gravity to pull it towards the planet. The deceleration increased steadily as the fuel tanks emptied and the ship grew lighter.

  ‘Two minutes to run,’ Clare reported, ‘Descent profile nominal.’

  The spaceplane swayed as the engines’ thrust vector was briefly directed off the centreline, to hold the correct attitude. The swaying increased, becoming more noticeable as the fuel tanks emptied and the ship’s centre of mass altered.

  ‘One minute to run.’

  It was getting harder to breathe now as the deceleration mounted, rising to two gees, and still it climbed. Clare moved her hand to the position where she could shut the engines down if they overran, and watched the seconds count down to cutoff.

  As the figures hit zero, the thunder of the engines stopped, and the sensation of crushing weight lifted from Clare’s chest. A long, declining wail came faintly through the craft as the turbopumps spun down.

  ‘Main engine cutoff,’ Clare reported, her voice sounding strange in the sudden quiet.

  The pitch thrusters fired at the command of the autopilot, and the spaceplane turned slowly end-over-end so that it was facing forward, nose-high to present the broadest surface to the oncoming atmosphere. Clare checked their attitude and re-entry angle once the manoeuvre was complete; any error could cause them to plunge too deeply into the atmosphere and burn up, or skip out again and miss their target completely.

  She rested her right hand on the sidestick, ready to take control if needed, but the autopilot was doing its job, following the descent profile perfectly.

  ‘Re-entry interface,’ she announced, and the ship shuddered as it encountered the first wisps of atmosphere on the edge of space. The spaceplane’s forward velocity had been reduced to four kilometres per second by the de-orbit burn, but they were still travelling at hypersonic speeds.

  A faint hiss grew at the edges of hearing, and increased until it surrounded the entire cabin. Through the narrow vision slit in the window visor, a bright glow flickered and wavered, growing in intensity until it filled the cabin with a pearlescent, white light. Clare felt herself falling forwards into her seat straps now as the spaceplane braked its forward velocity with the air resistance of the atmosphere.

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bsp; A sudden bump, and the ship lurched, then another, and then they were crashing and thumping through the searing-hot air. Clare kept her eyes on the instruments and the primary flight display, watching the autopilot make the necessary corrections. The nosecone and wing leading edge temperatures were increasing rapidly, climbing through 700 degrees, 800 degrees, and still rising. Cold fuel flowed through cooling channels in the nose and leading edges of the wing and fins, helping to carry away the intense heat, but the metal surfaces were glowing red-hot.

  The re-entry chop became more severe, bouncing them around in their seats. Something broke loose behind in the passenger cabin and banged to the floor. Clare could hardly read the instrument panel; her vision was a violent, dancing blur. The seat straps tugged painfully at her body as the negative gees mounted.

  The spaceplane lurched violently to one side, and for a few terrifying moments Clare thought the ship was going to spin and break up, disintegrating like a comet in the roasting heat of the sky. The turbulence decreased for a moment, and the ship steadied out, then it hammered against the ship with increased violence. She knew that spaceplanes had broken apart during re-entry when control had been lost; they must be very close now. She could feel the sudden shoves caused by the thrusters firing almost continuously to try to keep them stable …

  The wild ride lessened as the ship’s descent smoothed out, and the painful deceleration started to ease off. Outside, the freezing air at 140 kilometres high flowed over the glowing metal, cooling it down to a sullen red, then a dull grey. The spaceplane pitched forward, lowering its nose, and without any sense of transition, they were falling, arrowing down into the thin, cold air.

  It was eerily quiet after the noise and buffeting of re-entry, just the whisper of air rushing past the exterior, no sound of any engines. Clare exhaled slowly.

  ‘One of the more exciting rides I’ve had,’ Hartigan commented dryly, and thumbed the intercom: ‘Are you guys all okay back there? What’s come loose?’

  ‘A locker door came open – it’s a spare helmet. It’s stuck under my seat now,’ a voice responded.

  ‘Oh, okay. Try to hang onto it if it looks like getting loose again. We’re through re-entry now, and in the descent. Not long to go before we land.’ He cut the intercom and turned his attention to the descent display. They were passing 85 kilometres altitude, with most of their forward speed gone, in a steep descent towards the surface.

  ‘Carrier Two Eight Approach, Skydive One Four Seven. Re-entry complete and through eight five zero,’ Hartigan said, watching the altitude.

  ‘Skydive One Four Seven, Langley Approach. Reduce your descent speed to seven zero and left turn onto heading two eight zero.’

  ‘Reduce descent to seven zero, left turn to two eight zero, Skydive One Four Seven,’ Hartigan acknowledged. Clare pulled back gently on the sidestick to ease the spaceplane out of its steep dive, and banked to the left. The craft responded sluggishly to the flight controls; the air at this height was still too thin to provide much lift.

  ‘Visor down,’ Clare said, keeping her concentration on controlling the spaceplane as she turned out on their new heading. Hartigan reached out and operated the control, and the protective visor, which had covered the windows during the descent, lowered slowly.

  Light poured in as the visor sank out of sight, light from the Sun reflecting off the cloud deck far below them. They had entered the atmosphere over the night side of the planet, and were coming round into the dawn of the next day. The sky above the clouds was a deep blue, darkening to the black of space.

  ‘Sixty-nine kilometres altitude,’ Hartigan said, ‘deploying air data probes.’ On the side of the spaceplane’s hull, four small panels rotated to expose the delicate pitot tubes and angle-of-attack vanes to the slipstream. ‘Sixty-seven kilometres. Airspeed Mach one and falling.’

  ‘Roger. Relight sequence.’

  Hartigan reached up to the overhead panel and operated a switch to open the engine intakes. Held tight closed against the searing heat of re-entry, the intakes opened slowly like twin sharks’ mouths, gulping in the cold air. Deep inside the engines, the compressors started to turn from the windmill effect of the high-speed air rushing through them. Hartigan watched the revolutions build and the pressure ratios start to rise.

  ‘Sixty-four kilometres, starting two and three.’ He pulled the start selectors for the innermost two engines, and moved the fuel control levers to RUN. Nothing appeared to happen at first, then the whine of the spinning compressors was slowly replaced by a rising, muffled roar.

  ‘EGT and oil pressure rising,’ Hartigan confirmed, ‘starting one and four.’ He repeated the procedure for the outer two engines, and watched the engine displays as temperatures and oil pressures rose in all four engines. Relighting the turbojets after their long soak in the cold of space could be a tricky moment; the atmosphere of Venus did not support combustion, and the burners had to be relit on a carefully controlled mix of liquid oxygen and fuel. This time, however, the engines had all come up without any issues, and were settling out nicely.

  ‘All engines running and stabilised at flight idle.’

  ‘Set thrust.’

  Hartigan pushed the thrust levers forward to the middle detent and engaged the autothrottles. The roar of the engines increased as they came under the control of the autopilot.

  ‘One Four Seven, we have you descending through six three five. Descend and maintain six three zero, maintain current heading.’

  Hartigan acknowledged the instructions and Clare lifted the nose. The big delta wing bit into the air and the spaceplane levelled off at sixty-three kilometres altitude. She pressed the ALT HOLD button on the autopilot.

  ‘Four minutes to landing,’ Hartigan said quietly. ‘On course, thirty-five kilometres to run.’

  Clare nodded, concentrating on the controls and the scene ahead. The Sun was almost overhead now, and the sky had brightened to a pale blue, with a brilliant white deck of clouds beneath a faint haze.

  Time to bring their airspeed down. She selected the speed brakes, and on the surface of the wings, spoiler panels popped up. A roar of disrupted air came through the cabin walls as their airspeed bled away.

  ‘One Four Seven, descend to six two zero and intercept localiser for landing heading two seven zero.’

  Clare could see the localiser beam drifting across the navigation display, and she banked the spaceplane to the left so that the autopilot could capture it. She dialled in the lower altitude and the spaceplane tilted down towards the clouds. The controls were becoming more effective as the air grew denser, and the craft shook briefly as it flew through a swirl of turbulent air.

  ‘Gear down.’

  Hartigan moved the gear selector out of its detent and selected it to DOWN. There was a whine of actuators, and a rumble of air as the doors opened and the landing gear extended into the slipstream.

  ‘Down and locked,’ Hartigan confirmed, as the gear position indicators turned green. ‘Landing lights on.’ The spaceplane’s lights, two on the nose gear leg and one in each of the main gear bays, came on, four tiny suns in the blue sky.

  ‘Hook down.’

  Under the rear belly of the spaceplane, a long, thin arm of high-tensile steel ending in a flat hook lowered until it was trailing below the aircraft. This was the arresting hook, designed to catch and hold onto the arresting cable that was waiting for them.

  ‘One Four Seven, we have you on localiser. Descend to six one five and contact Tower on VHF.’

  ‘Two minutes to landing.’ Hartigan said as he selected the tower frequency, ‘you’re doing fine. Let me know when you want the landing checklist.’

  Clare didn’t respond, but Hartigan’s calm voice reassured her. Her breathing steadied, and she took her hand off the sidestick and flexed her fingers before taking it back again. As the spaceplane settled at its final speed of 140 metres per second, she withdrew the speed brakes and armed the autopilot for landing.

  ‘Skydive One Four
Seven, Tower. Maintain current height to intercept glideslope. You are number one for landing.’

  ‘Dump fuel to maximum weight.’ This was always a critical stage. The spaceplane was coming in with excess fuel in case it had to divert to another carrier, but the extra weight made it too heavy to land on the carrier’s deck. Once they dumped the spare fuel, they had to land, although they had enough fuel for several attempts.

  A stream of vapour erupted into the sky behind them as Hartigan opened the valves to vent their excess liquid oxygen overboard, then after a short pause the liquid propane followed.

  ‘Fuel dump completed, we’re down to five tonnes.’

  ‘Landing checklist,’ Clare said, her eyes flicking across the instruments. They ran through the items carefully, making sure that the craft was configured correctly, and that they hadn’t missed anything. They were only a minute away now.

  A symbol flashed on the flight display.

  ‘Glideslope captured. You’re established for landing,’ Hartigan added. The autopilot had locked on to the invisible radio beams radiating into the sky behind the carrier, and was adjusting their descent to bring them down onto the flight deck.

  ‘One Four Seven, we have you on glideslope. Maintain speed one four zero. Report visual and fuel state.’

  ‘Do you see them?’

  ‘No …’ Clare scanned just below the horizon. The haze above the clouds made it difficult to make out details. A sudden gust shook the cabin; the big spaceplane rolled slightly, and the autopilot compensated.

  ‘Five kilometres to run – we should be able to see the beacon.’

  ‘I see them. Twelve o’clock low.’ Clare’s sharp eyes had spotted it; a tiny dark shape moving against the clouds ahead and slightly below them. Suddenly it all seemed impossible. How could she land this huge spaceplane on that tiny speck? It was all happening too fast.

  ‘One Four Seven, carrier in sight. Fuel state is four decimal nine tonnes.’ Hartigan released the transmit and glanced down at the navigation display. ‘Four kilometres. You’re set up nicely. Just fly it in.’