January 29, 1998
DE RELEASE NO. 98-7
PHONE: (505) 846-6315
KIRTLAND AIR FORCE BASE, N.M. -- A series of wind tunnel tests, just completed, by Boeing in Seattle, Wash., has proven that the components critical to the performance of the Air Force’s Airborne Laser will work as they were designed.
The Airborne Laser (ABL), a warplane that will use a laser to shoot down theater ballistic missiles, is managed here by the Airborne Laser System Program Office.
The wind tunnel tests, which focused on the design of the nose turret and laser exhaust system, are the latest in a series designed to reduce technical risks on this $1.3 billion development contract.
Team ABL, comprised of Boeing, Lockheed-Martin, and TRW, is designing the Airborne Laser to counter the increasing threat of theater ballistic missiles to U.S. forces deployed overseas. The revolutionary system, which provides a speed-of-light response to missile attacks, will play a key role in the nation’s tiered, multi-service theater missile defense architecture.
Boeing engineer Victor Buonadonna, who directed the tests at the transonic wind tunnel adjacent to Seattle's Boeing Field, said that the tests of the 104-inch nose turret design had two primary objectives. "We wanted to minimize dynamic pressure (on the turret surface) and also optimize the passive flow control to reduce the effects of shear layer."
Confirming the performance of the Lockheed-Martin basic turret design and obtaining all the necessary dynamic pressure measurements allows Lockheed-Martin to complete its detailed design of the turret, Buonadonna said. "These tests exceeded our best expectations," he said, explaining, "We confirmed that the passive flow control of the turret is extremely effective and that a series of exhaust design candidates were refined."
The goal of the laser exhaust tests was to evaluate various flow control devices for minimizing exhaust effects on the airplane.
"The ABL government-industry team continues to deliver excellent progress – hardware is being delivered, and we’re right on schedule and on budget," said Col. Michael Booen, ABL program director.
Earlier tests disclosed that in certain turret positions, air flow (called the boundary layer) separated from the turret surface and created a turbulent "shear layer." That turbulence degraded the quality of the laser beam when the laser aimed through it.
Boeing is responsible for battle management, overall integration of the ABL and attachment of the turret to the nose of the modified 747-400F freighter. The optics and control of the laser beam that fires through the turret’s window are the responsibility of Lockheed Martin. TRW is designing and producing the weapon system’s powerful laser.
The program office is a unit of the Space and Missile Systems Center at Los Angeles Air Force Base, Calif.
The aircraft, which costs approximately $150 million, is slated for delivery in 1999 and scheduled to shoot down a boosting theater ballistic missile in 2002.
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