* No F-35 on day one of Farnborough air show, maybe later
* Engine fan blade broke off
* Issue not seen as "fundamental design flaw"
(Recasts with information about cause of failure)
By Andrea Shalal
LONDON, July 13 The engine failure that has
grounded the entire fleet of Lockheed Martin Corp F-35
fighter jets was caused by "excessive" rubbing of fan blades in
the plane's Pratt & Whitney engine, but does not appear
to be a fundamental design flaw, the Pentagon's chief weapons
buyer said on Sunday.
Defense Undersecretary Frank Kendall told reporters on
Sunday there was still a chance that the grounding order could
be lifted in time for the F-35 to make its international debut
at the Farnborough air show.
Organisers of the show confirmed that the F-35 would not
appear on Monday, but said it could still arrive and fly later
in the week.
The United States' newest combat jet had already been pulled
out of a British military show last week, after the entire fleet
was grounded following a massive engine failure on a U.S. Air
Force F-35 at a Florida air force base on June 23.
Kendall said the grounding had halted testing but he did not
view the incident as a "fundamental setback" for the $400
billion program, the Pentagon's biggest, which still has about
40 percent of developmental testing to complete.
He said the engine had suffered two issues involving fan
blades in the past few years, but they appeared unrelated and
not systemic to the airplane.
"None of those things that have happened, including this
recent one as far as I know, suggests that we have a
fundamentally flawed design," Kendall said.
He said detailed inspections of engines on the fleet of 97
F-35s already built had not shown signs of the kind of excessive
rubbing founded on the engine that broke apart, although there
were signs of milder rubbing in several other engines.
Kendall said the evidence being compiled did not point to a
systemic issue, but the analysis was still going on. In this
case, engineers found evidence of significant rubbing by the fan
blades against a cowl.
"We're not noticing it throughout the fleet," he said. "The
design allows for a limited degree of rubbing, but it was enough
in this case to cause a structural reaction that ultimately led
Bennett Croswell, president of Pratt & Whitney's military
engine business, declined comment on any details about the
engine failure and what caused it.
Marillyn Hewson, chief executive of Lockheed Martin, said it
was disappointing that the jet had not flown in Britain thus
far, but the company stood ready to support the jet if flights
were allowed to resume.
She said military officials from other countries were
supportive of the process now under way.
"People who understand the nature of development take this
in stride as normal discoveries in development," Hewson said.
(Additional reporting by Mark Potter; Editing by Kevin Liffey)