Whooshhh!

Supersonic business jets will use aerodynamic shaping to minimize sonic booms. Don't be alarmed by the lack of windows: Cameras will send exterior images to the cockpit and cabin.

Aerospace engineer David Graham and his three colleagues had a deadline, and a little brown tortoise was putting it in jeopardy. In a few hours, as the sun rose over the Mojave Desert on an August morning last year, two Northrop Grumman F-5E fighter jets would come racing over the horizon. Flying 30,000 feet above Harper Dry Lake and traveling at 920 mph, the airplanes would be trailing long sonic booms, the distinctive aural signatures of supersonic flight that ordinarily make high-speed passages over land impossible.

The engineers, all members of a Northrop Grumman?led research team working to make those signatures significantly less distinctive, expected the two booms would be different from one another - a difference too slight to hear, even with your ear cocked to find out whether a 30 year old theory aimed at mitigating supersonic shock waves worked in the real, turbulent and bubbly atmosphere, but one big enough to be detected by the instruments in the back of their SUV.

But this SUV, crammed with gear that had to be set out across the lake bed, wasn't going anywhere until the desert tortoise moved its reptile rear out of the way.