WASHINGTON, May 3 (UPI) -- The U.S. Army grounded nearly 1,000 Black Hawk helicopters late Wednesday after a crack was discovered in a part on the transmission of the transport aircraft, Army spokeswoman Nancy Ray said Friday.
The grounding order does not affect 584 "L" model UH-60 Black Hawks, and only applies to non-essential flying for 960 others. Black Hawks may be used for medical evacuation and combat operations as required, according to Ray.
Few Black Hawks are being used by U.S. troops in Afghanistan because they do not carry as much weight at high altitudes as Chinook helicopters, which have been employed extensively.
The part in question, a planetary gear carrier, has never been a problem in the history of the helicopter -- after more than 3.5 million flight hours, Ray said. It is not on a list of parts that need to be replaced.
A helicopter maintenance team at Ft. Bragg, N.C., discovered a problem in oil pressure on a single Black Hawk that could not be fixed following normal maintenance procedures. The team sent the helicopter to an Army depot maintenance facility at Corpus Christi, Texas. That team tore down the transmission and discovered the cracked part.
The grounding order "is a precautionary measure until they look at the part in question and determine what needs to be done," Ray said.
The Black Hawk, which entered service in 1978, is manufactured by United Technologies, Sikorsky Aircraft and General Electric.
