Vibrations During Launch Might Cause Severe Problems, USAF Says

 Air Force Officials, who are charged with safety during launch operations at Kennedy Space Center, are concerned that harmonic vibrations from the cluster of solid rocket boosters used on the Ares I-X could knock out both the launch vehicle's Thrust Vector Control and self destruct mechanism. The result, officials say, could be extremely dangerous for people living along Florida's east coast.

The concerns may delay or even cancel the planned August 30th test launch, according to an exclusive report in The Orlando Sentinel.

While the solid rocket boosters are proven technology, Jon Cowart, NASA's deputy Ares I-X program manager, told the paper that  "if you change little things, it's amazing the amount of reanalysis you have to go do. You're not starting from scratch. But you're not as far down the road as you probably thought you were."

The Ares-I will eventually carry astronauts back to the moon, but those missions aren't planned for more than a decade.

Engineers used the same self-destruct mechanism on the Ares I-X as are used on the shuttle, but the vibrations during launch are apparently much more severe. According to internal NASA documents obtained by the paper, the vibrations with enough force to knock out the self-destruct mechanism could come 60-90 seconds into the flight, with a TVC failure coming as much as 2 minutes into the flight. The Air Force requires an assurance that the self-destruct system will work properly, 99.9 percent, according to Lt. Col. Loretta Kelemen, head of the Cape Canaveral Air Force Station 45th Space Wing Range Safety Office. "If they do not meet our requirements, then they do not launch here."

Cower told the paper he doesn't think the vibrations, which are called "sympathetic" among the SRB's and could cause the vehicle to act like a tuning fork, will ever be severe enough to effect either the Thrust Vector Control or the Flight Termination System. "We've done our analysis one way. They do it another way."

FMI www.nasa.gov, www.patrick.af.mil/