The shuttle's starboard airfoil had swept over the roof of the security groundcar, missing it by half a meter. Silver realized with a guilty shudder that she should have checked its height before she began to move. She might have torn the wing right off, with ghastly chaining consequences to them all.

The security guards were nowhere to be seen—no, there they were, scattered out onto the dry lake bed. One picked himself up out of the dirt and started back toward the groundcar. Now what? If she parked, or even rolled some distance and parked, they would only try again. It couldn't take too many more attempts till they got smart and shot out the shuttle's tires or otherwise immobilized it. A dangerously unstable stand-off.

Silver sucked on her lower lip. Then, leaning forward awkwardly in a seat never designed for quaddies, she released the brakes partway and powered up the port engine. The shuttle shuddered a few meters farther forward, skidding and yawing. Behind them, the monitor showed the groundcar half-obscured by orange dust kicked up by the exhaust, its image wavering in the heat of it.

She set the brakes as hard as they would go and powered up the port engine yet more. Its purr became a whine—she dared not bring it to the howling pitch Ti had used during landing, who knew what would happen then?

The groundcar's plastic canopy cracked in a crazed starburst and began to sag. If Leo had been right in his description of that hydrocarbon fuel they used downside here for their vehicles, in just a second more she ought to get . . .

A yellow fireball engulfed the groundcar, momentarily brighter than the setting sun. Pieces flew off in all directions, arcing and bouncing fantastically in the gravity field. A glance at her monitors showed Silver the security men now all running in the other direction.

Silver powered down the port engine, released the brakes, and let the shuttle roll forward across the hard-baked mud. Fortunately, the old lake bed was quite uniform, so she didn't have to worry about the fine points of shuttle operation such as steering.

One of the security men ran after them for a minute or two, waving his arms, but he fell behind quickly. She let the shuttle roll on for a couple of kilometers, braked again, and shut the engines off.

"Well," she sighed, "that takes care of them."

"It certainly does," said Madame Minchenko faintly, adjusting the monitor magnification for a last glance behind. A column of black smoke and a dying orange glow in the distant gathering dusk marked their former parking place.

"I hope all their breath masks were well filled," Silver added.