Posted on 02/22/2013 5:01:05 PM PST by Yo-Yo
All Lockheed Martin F-35s are grounded while the programme investigates the root cause of a crack discovered on 19 February in a third-stage low-pressure turbine (LPT) blade deep inside the Pratt & Whitney F135 engine.
The discovery of the blade crack comes five years after the first flight of the F-35B short take-off and vertical landing (STOVL) variant was delayed several months due to fatigue-related blade failures in the third-stage LPT.
The latest crack - discovered only days after the F-35B returned to flight following a 25-day grounding caused by a fueldraulics failure - was discovered on 19 February by a borescope inspection on an F-35A at Edwards AFB, California, and confirmed by an eddy current inspection, P&W says.
"It is too early to know the fleet-wide impact of this finding," says the Joint Program Office (JOPO). But all F-35s are grounded "until the investigation is complete and the cause of the blade crack is fully understood".
The engine in the 19 February incident has run a total of around 700h, of which 409h were flight hours, P&W says.
Though the issue was found in a single engine, there was no clear cause behind the crack. The engine's turbine module has been shipped to P&W's Connecticut test facility for closer inspection.
"We will conduct more thorough evaluations to determine the cause of the indication of the crack," the engine maker says.
Lockheed referred all questions about the grounding to the international joint programme office.
Two previous incidents with the third stage low pressure turbine blades have resulted in F-35 groundings in the past, once in 2007 and again in 2008. Those incidents, which both occurred in the F-35B vertical-takeoff variant, were traced to high-cycle fatigue. Unexpected vibration levels were caused by interaction of the the blade with the wakes from vanes upstream of the third-stage turbine.
The troubled aircraft programme, meant to provide a new fighter-bomber for all three major services of the US military, has been grounded several times before.
Gee yet another major procurement program FUBAR
Pratt & Whitney just ain’t what they used to be.
Blade failure can be pretty bad news in a single-engine STOVL airplane.
And the US has the capability to produce better trained pilots than any other country on Earth. (Maybe Israel can do better, but they aren't talking). The world comes here to learn how to fly fighters.
So with that in mind, what are we doing? Building fewer fighters. More complex and apparently more delicate fighters. Go figure.
We would do well to remember Stalin's axiom "Quantity has a quality all its own".
Nothing is what it used to be.
Wish we could just buy some more F-15SE and build the F-22 numbers up to what they were supposed to be and SK the F-35. It jut isn’t worth it.
Yeah, well, asking the USAF brass to buy more of a 20 year old design is like asking your wife to buy a 20 year old dress at the consignment shop. Gotta have what’s in the show windows at the mall!!!
No, my wife goes for the forgotten (modest) fashions at the thrift store every time.
Not quite the same thing. The cheaper, ligher, smaller plane can't carry the fuel or weapons to prevail in a real fight. They can only prevail in the instructor/student scenarios set up by Red Flag and Top Gun.
Put her in charge of weapons procurement, pronto!!
That almost reduces it to a knife fight right there.
That was Vietnam. We now live in the age of AWACS.
We would do well to remember Stalin’s axiom “Quantity has a quality all its own”.
The Russians did this with cheap, effective, and cleverly-designed weapons that could be churned out and used by semi-skilled people in WWII. And, except at the end of the war, any honest person would agree that our equipment was markedly inferior to virtually all of the German and a lot of the British equipment. But we made a hell of a lot of it and we had a lot of people trained and eager to use it.
Arthur C. Clarke wrote a science fiction story early in his career that chronicled the failure of a technologically superior, but overly complex military in a future war between planetary systems.
IMO, much of our high-tech military equipment is in danger of being overwhelmed by mass numbers of cheap or decoy weapons. The Iranians are counting on this, because it is their only chance. Same with Hamas, with their ten dollar upscaled bottle rockets requiring a $20K anti-missile missile to counter them.
OK, I stand corrected. Still, if I had to go up against 1000 of China or Russia’s latest with their pilots I’d rather have 1000 of the latest F-15/F-18s than 150 F-35s.
Absolutely. We are now the Germans with a hundred Tiger tanks facing our enemies with a thousand M-4 Shermans. Not where I want to be.
I hate this plane. I dont understand how or why unit costs have exploded. My guess as to why unit cost hyper inflation happens in the prime bidder on the contracts must outsource every single part down to the smallest. I would guess every one of the outsourced companies oursource everything else to a point where every single part is inspected and slightly turned through a super complex supply chain that only exists to supply one project.
I dont care if this is the greatest attack aircraft of all time, I dont think we can afford it, that its high cost is proof that we cannot make our own stuff in america any more.
I bet this F-35 project produces about the same number of units that the f-22 project. I dont see any need to lay down anymore keels for CVNs because we will not have the number of aircraft to make them a threat. We wont need many future pilots eather because we just wont have seats for them. I find to unbeliveable that we used to do fly offs to see who would win contracts, not we bribe contractors to produce aircraft with over inflated contracts.
Who would like to be the first guy to crash one? How can we afford to lose one in combat. I respected the B-2 price for the reason it was a first strike nuke bomber that could lay waste to nations.....I just dont see that kind of fire power here.
We became weak when we started to belive our own movies. Gosh just look at how the tababan wasted the Marine CO and his crew chief and 5 hornets in a desert rat attack months back.... 10 dirt bags and a crew served weapon in the back of a $500 pickup truck....We better spend billions on ABGD.
Not one type.
One airframe each.
They'll be GREAT planes. Probably able to outfight the Millenium Falcon.
But if those two planes go down, we could lose air superiority to a couple of beat out MiG 21s.
To me the F-35 is the modern day version of the F-3 Demon.
Reminds me a an old Air Force joke I heard many years ago during the cold war. In the future, the USA will develop a fighter that can single handedly destroy the entire Soviet fighter force.... and we will only be able to afford one of them!
What do you expect for a mere $300M a copy for a single engine fighter.
“In February 2011, the Pentagon put a price of $207.6 million for each of the 32 aircraft to be acquired in FY2012, rising to $304.15 million ($9,732.8/32) if its share of RDT&E spending is included.”
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