McDonnell Douglas C-17 Grounded Third Time

The Air Force has grounded the McDonnell Douglas C-17 cargo jet for the third time since October, the result of problems with leaky fuel tanks, service officials said Friday.

A congressional source said the Defense Department’s inspector general was launching an investigation into a number of facets of the C-17 program, including the fuel tank problems and earlier allegations involving improper installation of rivets on the wings.

McDonnell officials would not comment.

The latest grounding of the C-17 test aircraft occurred Sunday. The plane has lost 66 days of flight-testing at Edwards Air Force Base since its first grounding Oct. 31.

Repairs are time consuming because the aircraft’s massive fuel tanks must be drained and purged of fumes before workers can be dispatched into the bowels of the wings to seal the leaks.

An Air Force spokesman at Wright-Patterson Air Force Base, Ohio, said the leaky fuel tanks are “not a major problem as far as the design of the airplane.” Since its first flight last summer, the C-17 test plane has made 45 flights, he noted.

However, the congressional source said that the leaky fuel tanks represent a potentially serious problem that is delaying the flight-test program.

McDonnell recently has asserted that the C-17 program is going well, overall.

McDonnell issued a press release last month quoting Air Force Brig. Gen. Kenneth Miller, the program’s director, as saying that productivity had improved much more quickly on the C-17 program than on other projects and that “the quality is going up tremendously.”

McDonnell is preparing to fly a second experimental aircraft, although it missed an internal company schedule that called for a flight last month, according to knowledgeable sources.

The first grounding began Oct 31 and ended Nov. 20. The plane was grounded again from Jan. 28 through Feb. 20. The Air Force spokesman said that the service expected the C-17 test flights to be resumed “shortly,” perhaps as soon as next week.