(Adds comment from Norwegian official)
FARNBOROUGH, England, July 16 (Reuters) - The engine failure that grounded Lockheed Martin's F-35 fighter jets and the warplane's now-cancelled appearance at two UK air shows provided key "lessons learned" for the companies that build the jets, and the military forces that use them.
While the outcome was disappointing for air show visitors and many people involved in the F-35 program, U.S. military and industry officials said both the engine incident and air show planning allowed them to learn a lot about handling future problems and taking the jets overseas.
The $400 billion weapons program is the world's largest single arms project and encompasses three different U.S. military services, eight countries that helped fund the plane's development, two other foreign militaries, and a separate Pentagon office, as well as three separate aircraft models.
U.S. military officials on Tuesday announced that they had approved limited flights of the F-35 jets but imposed mandatory engine inspections and various flight restrictions, and banned the planned flights to Farnborough air show.
The latest grounding - the program's 12th to date - was not the longest, but it was complicated by the fact that U.S. and British jets were due to leave for Britain just days after the Pratt & Whitney F135 engine on an Air Force jet broke apart and caught fire at a Florida Air Force base on June 23.
Strict Air Force protocols for safety investigations - which include quarantining the affected jet - also meant that engineers from the Pentagon and engine maker Pratt did not have access to the affected jets for days, which slowed efforts to get the jets flying again.
Orlando Carvalho, executive vice president of Lockheed's aeronautics division, told Reuters on Wednesday that Lockheed and its key suppliers learned a great deal while preparing for what would have been the F-35's first foreign deployment, building on the planes' first deployments to the USS Wasp for testing in 2011 and 2013.
He said Lockheed developed detailed plans for transporting and storing spare parts, provided maintenance support and tested international use of the computerized logistics system called ALIS that stores mission plans and maintenance data - and all those systems worked well.
Carvalho said he was less concerned about hashing over what happened in this incident than ensuring improved procedures to deal with any future mishaps. Any changes to procedures would be led by the government in consultation with industry, he said.
"The fundamental question coming out of the last three weeks is, okay, if this were to occur again, how do we do this better?" he told Reuters at the Farnborough air show that was supposed to celebrate the new jet's international debut.
He said differentiated plans were needed to deal with incidents that affected each separate model, as well as those that were common to all three.
Air Force Lieutenant General Christopher Bogdan, the Pentagon's F-35 program chief, told reporters earlier this week the program would review and revamp current communications procedures about accidents and other safety concerns.
Marine Lieutenant General Jon Davis, who took over as deputy commandant for aviation on July 1, said the military was used to doing "after action reports" about what went right and wrong on any military operation.
"We are going to get smart about how we do things as a joint program. That will probably be the number one thing that comes out of this," Davis said. "I can guarantee that we'll come up with a little bit different construct for the next time around."
Davis said the services' needed to retain the responsibility for investigating accidents and mishaps, but it was critical to do that in a way that allowed sharing of information, at an appropriate level, with affected other operators.
He said the services should also look at ways to ensure quick sharing of data about pilot training and procedures, as well as emergency response procedures, as more and more jets are fielded in a growing number of countries in coming years.
Endre Lunde, F-35 spokesman for Norway's defence ministry, welcomed the effective safety procedures used in this case.
Lunde said the latest incident had "highlighted some challenges in how we handle such incidents in a large multinational program, and we expect that this also will be subject of review in the time going forward."
Paul Adams, president of Pratt & Whitney, said the fact that the program was still doing developmental testing while already producing larger numbers of jets - a practice called concurrency - had actually helped officials get more insight earlier in the performance of the engines and other components.
Far more F-35 jets were in use now for testing and training than is typical at this stage in a normal development program because of concurrency, he said.
Marine Corps Captain Richard Ulsh said cancellation of the F-35's appearance at the air was unfortunate for show planners and visitors, but provided valuable training for the Marines.
"We learned how to logistically support the F-35 on a different continent and most importantly we safely returned the aircraft to flight in a relatively short amount of time to continue training pilots," he said. (Editing by Mark Potter and Keiron Henderson)