Absence of flaws surprises US manufacturer as system proves dependability after 50 operations since December
Boeing is acknowledging surprise that no serious design flaws were found during the first major series of tests on the laser modules and optics systems for the US Air Force’s YAL-1 Airborne Laser (ABL) missile-defence platform.
“We were prepared for the potential for finding some more substantive changes and they simply have not materialised, so we’re very encouraged by that point,” says Scott Fancher, Boeing’s ABL programme manager. “We really found no fundamental flaws in the design of the laser, nothing that would force us to go and change the internal geometries of the chemical flows, for example, within the laser itself,” he says.
The ABL is being prepared to demonstrate by 2008 its ability to destroy an intercontinental ballistic missile (ICBM) in its boost phase. Flight tests in February and March validated the aircraft’s airworthiness, producing no unexpected findings. Next, the programme began to test the interfaces between the battle management system, which tracks the ICBM, and the beam control system, which aims the laser at the missile. Fancher says the reliability and robustness of the laser design has been the most encouraging result of the tests. In 50 laser operations since December, the system’s unexpected dependability has come as a relief.
Boeing has fired the laser eight times in 24h and has also performed several back-to-back firings, “where we’ve operated the laser, safed the test stand and then gone directly into a second laser operation within 10min. All these are encouraging results for us,” says Fancher. The tests also have shown the chemicals used to produce the laser beam can be stored on board the aircraft for up to 14 days, when five or six days had been predicted.
As tests continue, the programme also has started working on sorting out future plans. An order for a second ABL platform, presumably another heavily modified Boeing 747, is due in 2008, and the initial studies on cost and performance trades has begun. A key decision is to determine how many laser modules are needed to support the mission. The ABL testbed is now using six, but the programme is considering adding up to eight more. “It’s pretty clear from a cost-benefit perspective [that] fewer, more-efficient modules is going to be a better solution than more less-efficient modules, so where do you invest future development dollars goes into that as well,” says Fancher.
STEPHEN TRIMBLE / WASHINGTON DC
Source: Flight International
