Heineman piloted the V/STOL alone, using the aircraft’s rocket to push the tuberider along the axis from the first chamber bore hole. It had been only forty minutes since he had linked the tuberider and V/STOL in the south polar bore hole. The “ground” surrounded him on all sides, giving him a peculiar sensation of vertigo at first; which way should he orient? But he adapted quickly.
Using radio beacons set up in each chamber, coordinating through the V/STOL’s guidance computers, he could tell his position within a few centimeters. Cautiously and lovingly, he eased the assembly from chamber to chamber, using temporary propulsion packs on the tuberider and the aircraft, coordinated through the aircraft’s own customized guidance system.
Coming up on each bore hole was a thrill that raised the hair on his neck. In the center of the massive gray caps, that tiny hole—wider than a football field, no challenge really, but from a distance almost invisible ...
He flew steadily over the fifth chamber’s darkly Gothic landscape of clouds, mountains and chasms. Entering the bore hole between the fifth and sixth chambers, he issued a terse instruction to a crew of his engineers waiting near the seventh chamber singularity: “Take ‘er down. I’m coming through in a few minutes.” They acknowledged and began to dismantle the top of the research scaffold.
It was Heineman’s intention to thread the needle without readjustment, slowly but expertly.
The mated vehicles were monstrous from an aerodynamic viewpoint, and cumbersome from any perspective, but the flight was not difficult.
The near-vacuum of the Stone axis offered no resistance.
Even concentrating on the last phase of the delivery, Heineman couldn’t stop thinking about flying the aircraft.
Reentry was the uncertain part. Once the tuberider was threaded and steady on the singularity, Heineman would test the clamps by moving thirty-one kilometers down the axis.
Descent would be much less complicated so he was told—hat far down the corridor; he could descend in almost a straight line instead of the spiral necessary within the rotating chamber.
The V/STOL would unlink and propel itself away from the axis with short bursts from hydrogen peroxide motors. Then it would fall steadily, encountering resistance at the level of the atmosphere field barrier and plasma tube, about twenty-two kilometers above the chamber floor, three kilometers from the axis. Jets and upwellings from coriolis and compressional heating made the first thin kilometer of air tricky; the V/STOL's pilot would have to forget a lot of the truisms learned on Earth.
The designers had estimated the aircraft’s fuel use. It could make twenty ascents and descents, and fly approximately four thousand kilometers at cruising speed in the air, before having to tap the tuberider fuel, oxygen and hydrogen peroxide tanks.
Fully loaded, the tuberider could refuel the V/STOL five times.
And when it was clamped to the singularity, the tuberider could travel indefinitely using the spacial transform effect.
Now, both plane and tuberider were traveling light. Once they were threaded, crews could load them with fuel and oxygen from the staging area of the seventh chamber bore hole.
The sixth chamber rotated around him, a cylindrical cloudscape with broken patches revealing the machines he had only learned about three days before.
He was half-convinced the archaeologists and physicists had conspired to keep him away from the most interesting parts of the Stone out of sheer spite. ”No moving parts,” Carrolson had said. ”We didn’t think you’d be interested.” He gritted his teeth, then blew out his breath with a whistle. The sixth chamber machinery was overawing. He had never dreamed he would see anything like it, even on the Stone. It almost took his attention away from piloting the tuberider and V/STOL.
The last bore hole approached rapidly. He slowed the assembly and nudged the craft one last time. Allowing for some mid-hole corrections and drifts caused by irregularities imposed on the Stone by its Earth-Moon orbit, he would be able to slide right onto the singularity, slow the assembly with the clamps and then proceed with the tuberider test.
“There it is,” Carrolson said, pointing. She stared through the polarized and filtered binoculars at the plasma tube where it joined the southern cap, then handed the glasses to Farley.
Farley squinted through them and clearly saw the mated vehicles, seemingly poised without support; the singularity was impossible to make out from this distance.
“He’s going to fly it down today?”
Carrolson nodded. ”Heineman will try it out and stay here until Lanier returns.”
Rimskaya walked up behind them and stood silent while they passed the glasses back and forth. ”Ladies,” he said some moments later, “we have work to do.”
“Certainly,” Farley said. Carrolson grinned behind Rimskaya’s back.
They returned to the tent.