Morrow nodded. They had worked night and day to construct the second, smaller ship—a little two-passenger job with sweptback fins and a canopy-covered cockpit in its sharp nose. It rested neatly on its long A-fins, poised to hurtle into the sky. Its color scheme—dark blue-black on top, light gray on its belly—stood out in sharp contrast to the solid, shimmering black of the giant ship behind it.
It had been Foster's idea. He'd pointed out to them that they needed a smaller experimental model, easier to dismantle and rebuild, for the development of their air-jet chamber.
"Have you given it a test-flight yet?" Foster asked.
"Ran it out last night," Smitty replied, coming around the two ships to meet them. He set a plumber's blowtorch on the workbench and wiped his hands on a rag. "It hit seventy miles an hour, then worked up to seventy-four after a five-hour run."
Foster shook his head in puzzlement. "That's something I just can't account for. A jet-pod ought to be just as efficient as its design, and nothing should alter its basic performance other than a change in atmospheric conditions."
"There was no atmospheric change," Morrow said. "Same altitude, same barometric pressure, same thermal conditions. I'm beginning to think the problem isn't only in the jet-pod design."
"That makes two of us!" Foster agreed. "The design I gave you should've worked better than any seventy miles an hour, if your propulsion unit develops that focus of 'false gravity' and squeezes the air out, forming a low-pressure center, as you said it did."
"We've checked that, too," Morrow said, frowning thoughtfully. "I'm beginning to think it's something to do with the gravitors' field of influence. Come over here—I want to show you something!"
He led the jet engineer over to where he and Smitty had rigged a gravitor mechanism and a sling-load of sandbags with rope attached, just as they'd used in weight-testing the gravitors. He switched on the gravitor, adjusted its setting, and let it lift the load of sandbags into the air. Then he pointed to the rope dangling down beneath it.
"See that twist in the rope, just under the sandbags?" he said. "That much of the rope is in the influence of the gravitor's field, which is cancelling out the pull of the Earth's gravity. Now then, if it can influence that three-foot length of rope, what influence might it have on the air around it—and on the slipstream of air flowing over our ships, which is supposed to enter the air-vents and be blasted out the jets for propulsion of the ships?"