WASHINGTON, D.C., 14 April 2005. When the Space Shuttle Discovery (STS-114) returns to flight next month, it will have a special escort. But the pair of NASA WB-57 chase jets won't just be along for the ride.
Thanks to an engineering team that includes NASA's Marshall Space Flight Center, Huntsville, Ala. and key industry partners, these high-flying chase planes will provide NASA with extra "eyes in the sky" to watch Discovery's flight and help safeguard its crew.
The jets will carry innovative, on-board video imaging systems, dubbed the WB-57 Ascent Video Experiment (WAVE). The system will capture detailed images of how the Space Shuttle behaves as it climbs toward orbit. During the launch, the jets will keep pace with Discovery, flying at a distance of 15 to 20 miles. The WAVE systems will track the shuttle for approximately 150 seconds, from liftoff to separation of the solid rocket boosters, the power systems that provide its main thrust.
After determining a piece of insulating foam from the external tank damaged the Space Shuttle Columbia just after liftoff, the Columbia Accident Investigation Board recommended NASA improve imagery during orbiter ascent. The chase-plane imagery is part of NASA's response to the recommendation.
"Shuttle video captured by the chase vehicles will help us see the launch in greater clarity than ever before," said Project Manager Bob Page. He leads NASA's Inter-Center Photography Working Group at the agency's Johnson Space Center (JSC) in Houston. "Along with cameras on the ground, and in and on the shuttle itself, this imaging system will provide an unprecedented look at Shuttle liftoff and atmospheric flight," he said.
NASA video technicians built and tested the high-definition imaging system earlier this year. They called in optics specialists from Marshall's Space Optics Manufacturing Technology Center to design the camera lens and split the video feed, enabling it to simultaneously record the shuttle in visible light and infrared.
Mechanical engineers from the University of Alabama in Huntsville, Ala., built the housing. Programmers from San Diego-based SAIC, a NASA contractor, helped integrate the cameras and recording system.
"This was the very definition of a team effort," said Marshall optics engineer John West of the Space Optics Manufacturing Technology Center. "In June 2004, we were looking at nothing more than a concept on a drawing board. In nine months, we built two complete imaging systems."
Just one issue remained: how to get the complex, bulky WAVE systems airborne. Each system had to be mounted in the nosecone of the chase planes, using a large gimbal, a stabilizing anchor to keep the cameras focused on the Shuttle, even if turbulence caused the plane to dip or drift. The WAVE team turned to Southern Research Institute (SRI) in Birmingham, Ala., for the solution: a gimbal system similar to ones the firm built to support U.S. Army missile tests.
According to John Collier, senior program manager for SRI, the company designed and built a new gimbal to suit NASA's needs by using a lightweight, carbon-graphite epoxy. In March, the firm integrated the WAVE systems with the gimbals. The systems will be shipped this month to Ellington Airfield near Houston, where they will be mounted on the jets.
"Across the agency, we're all working to make the Space Shuttle safer," said Marshall Project Lead Rodney Grubbs. "This was our opportunity to contribute, and we're excited about what our imagery might mean for the safety of our astronauts."
Managed by JSC, the WB-57s are former U.S. Air Force planes designed to study weather conditions at high altitudes. When the Air Force phased out its WB-57s in the 1970s, it transferred two of the jets to NASA. NASA's are the last two WB-57s still flying. For more information, see www.nasa.gov/returntoflight/.