When Boeing successfully launched its Delta IV rocket last month, there was more riding on the event than the $1 billion telecommunications satellite attached to its tip. Also at stake was Boeing's piece of the global launch-services market, a lucrative business opportunity that could help offset some of the company's losses in its commercial airplanes division, which has cut nearly 30,000 jobs since Sept. 11, 2001.

	Linux helped keep development costs for Delta IV low.

Getting the Delta IV from the launchpad into space required years of design and computational fluid-dynamics testing to understand the impact of flight on the rocket's structure and control system. Aerodynamics engineers with Boeing's Expendable Launch Systems division in Huntington Beach, Calif., used a 96-node cluster of PCs with Advanced Micro Devices 850-MHz Athlon processors running Red Hat Linux, rather than a $500,000 supercomputer, to keep costs low in pursuit of its goal. Linux cluster-management company Linux Networx helped to develop the environment.

"The Linux route was newer and had more risks, but sometimes you have to take some risks," says Scott Ward, the Boeing Delta program's manager of aerodynamics. Ward wouldn't say how much his department paid for the AMD Linux cluster when it was implemented in 2001, but he says it will continue to pay "huge" dividends as Boeing adds nodes to increase computing power.

Boeing plans to launch as many as five Delta IV rockets next year. The next mission will deploy an Air Force Defense Satellite Communication System. Last month's launch carried a telecommunications satellite built by Alcatel Space.