"Flaw Could Shorten Raptors' Lives"

Flaw Could Shorten Raptors' Lives
Military.com | The News Herald, Panama City, Fla. | May 03, 2006
The F-22A Raptor has been designed with a service life of 8,000 flying
hours, but a faulty manufacturing process discovered four months ago
may cause a key structural component in 90 of the new fighters to age
prematurely, officials said Monday.

The "forward boom frames" in the 62-foot-long fighter are constructed
of titanium, a lightweight but extremely strong metal, and are used to
anchor the aircraft's wings to its fuselage, said Air Force spokesman
Doug Karas. During routine testing in December, Karas said, officials
discovered that the titanium components may have been "improperly"
treated, creating the possibility that the metal would not last as long
as it is supposed to.

The flawed components, Karas said, "do not affect safety of flight and,
consequently, no restrictions have been put on F-22 flight operations."


The problem affects Raptors No. 4017 through 4107, including most of
the 66 Raptors that already have been delivered to the Air Force and
several dozen more still being manufactured, Karas said. There are 23
Raptors assigned to Tyndall Air Force Base for F-22 pilot training with
another six scheduled to arrive in the next year.

"This is not a result of improper design, but an issue with one
supplier's manufacturing process," Karas said in a statement to The
News Herald.

A spokesman with the Lockheed Martin Corp., prime contractor for the
F-22, said Monday the company is working closely with Air Force experts
to determine the extent of the problem. Structural tests including
"fatigue" tests of the fuselage booms are continuing, said company
spokesman Joe Quimby.

Under a "heat treat" process, the titanium boom frames are raised to a
high temperature in order to "achieve the desired grain structure" in
the metal, Karas said. "A section of the forward boom frames under
investigation may not have been held at this temperature long enough"
to reach the targeted strength, he said.

The trade publication Defense News reported Monday that it will cost
about $1 billion to fix the flawed boom frames, but both Karas and
Quimby flatly denied that allegation.

Raptor program officials also have identified the need to reinforce the
aft boom in 41 of 73 Raptors to strengthen the juncture where the tail
is attached to the fuselage, according to Air Force officials quoted by
Defense News. (Of those 73 aircraft, 66 also are affected by the
forward boom heat-treatment flaws, officials said.)

An Air Force spokesman told Defense News that the discovery occurred as
part of the normal testing process for each new aircraft design.

"As the aircraft come down the production line, they continue to test
the fleet," said Maj. Keith Scheirmann, chief of Raptor heavy
maintenance and modifications at Wright-Patterson Air Force Base.
"Sometimes, we find areas where we want to go back and enhance the
capability or upgrade the aircraft," he told the publication.

Still, fixing the problem in each airplane could require removing the
wings to inspect the boom area, a time-intensive and expensive process,
officials said.

The Air Force and Lockheed Martin are conducting further tests at a
company facility to determine the severity of the problems and hope to
have answers by the end of May.

The Defense Department and Congress have agreed to cap the F-22 program
at 183 aircraft. Lockheed Martin has contracts to build another 107 of
the advanced fighters, Quimby said.