54 Marines, USAF Tiltrotors Affected; Possibly More

It's one of the last things the fledgling V-22 Osprey program needed... another grounding, this one caused by an alleged manufacturing defect in a single computer chip.

Stars and Stripes reported over the weekend Naval Air Systems Command grounded a total of 54 of the revolutionary tiltrotors -- 46 Marine MV-22 variants, and eight Air Force birds -- due to the computer problem, which engineers traced back to a faulty computer chip in the Flight Control Computer.

Engineers at the Bell-Boeing V-22 joint manufacturing facility in Amarillo, TX noticed the glitch during diagnostic work, according to the Associated Press. The chip, which helps backup control systems take over in the event of primary control systems failure, malfunctioned at temperatures below 30 degrees F -- far above what the specs call for.

"The specs say that all Osprey systems should work down to 65 degrees below zero Fahrenheit, so it was definitely a problem that the flight control computers started acting strange when the temperature was just below freezing," said Bell-Boeing spokesman Bob Leder.

Replacement of the chips, which were manufactured by Texas Instruments, is expected to take a few weeks... although officials at the Dallas-based computer company hesitated to take the blame for the problem.

"We are nowhere near ready to say that any of our chips did anything they shouldn't," said TI spokesman Gary Silcott. "We don't even know that our chips had anything to do with this."

"We called BAE [Systems Inc.], the company that makes the flight control computers, and they traced the problem back to this one chip, which is apparently an off-the-shelf product and not something that Texas Instruments specifically designed for this project," replied Leder.

Osprey program spokesman James Darcy said it's likely most Ospreys have the bad chips... but he declined to state how many aircraft that actually translates to.

FMI: www.boeing.com/rotorcraft/military/v22/index.htm