Above the roar, a brilliant arc of electricity suddenly exploded just in front of the nose of the model, adding an additional burst of pressure at Mach 6 to the velocity already passing across. It was a blinding, microsecond pulse that momentarily boosted simulated vehicle velocity to Mach 13. The lasers registered the data, then passed it directly, via microwave link, into the memory banks of the powerful SX-10 operating hundreds of miles away.

Seconds later the turbulence data appeared in visual form on the liquid crystal screen above them. As the colored numbers flashed, a cheer went up from the normally somber technicians.

"Still no sign of any wave drag outside the theoretical envelope, not even at Mach 13," the young head-technician beamed.

"Just as we simulated," Ikeda noted quietly.

This time even the grave Androv smiled. "I must congratulate all of you." He was rising from his chair, the central one facing the main controls.

"Then I will order the modification installed," Ikeda nodded, "if you formally authorize it."

"Authorized. I think you are right. Perhaps we are ready for a hypersonic test flight." Androv reached to switch off his turntable. "I would like to go down to the hangar now myself, in fact. Perhaps celebrate this moment with a glass of tea."

"Of course." Ikeda spoke quickly to his Japanese technicians, then followed the Russian out the door.

The hallways were a connected maze of brilliantly lighted and scrupulously clean tunnels. They moved down the main corridor to the central checkpoint, then turned and entered the South Quadrant, passing the various assembly sections. Those sectors were mostly quiet now, since the final work had been completed several weeks earlier.

Androv said nothing as they walked toward the doorways connecting the South Quadrant with the underground hangar. He merely whistled a portion of the third movement of the A Minor quartet, Beethoven's hymn of thanksgiving in the Greek, Lydian mode. He recalled that the English writer Aldous Huxley had once suggested that particular movement was proof of God's existence.