F35s grounded.
 

F-35s grounded by engine risk
 

F135 engine LPT blade found cracked during inspection:

UPDATE 3-Pentagon suspends F-35 flights due to engine blade crack | Reuters

According to that first article, both F35s and Harriers have less range than the SEP training aircraft I currently fly in!

"Defence Specialist" Mikey Kay due on Sky News in a few minutes, He's a Rotary Bloke

No sh1t Sherlock.

I just hope they ship all the blades from that turbine.

Not an Aircraft Engineer but...

Do we not get turbine blade failure on other engines/fleets and would the whole fleet be grounded then? Notwithstanding of course the recent introduction of the F35 and the obvious lack of history when compared to say the Tonka fleet.

Also comparing fleets what would the number of blades/engine be between say the F35 vs Tonka fleets.

Yes there was this one as an example


160784 B Second TFA-18A (later designated FA-18B). McDonnell Douglas, crashed 8 Sep 1980 Mildenhall Royal Air Force, Middle Wallop, Hampshire, UK near Farnborough after engine failure. MD pilots Jack Krings and Gary Post ejected safely.


They had a big TV request on the news and offered locals and local schoolchildren a reward for any parts of the turbines found and managed to recover most of it to find out what went wrong

The Gazelle 163 ( I think- the one in the Wessex 3/ 31 series) was prone to shedding compressor blades. That caused the loss of several aircraft and at least one RAN fleet grounding. The cause was usually an installation issue with the root.

N

If this is to be a competent investigation, USAF should send the ENGINE back to P&W for analytical teardown. I say this because it's possible - maybe likely - that the root cause lies elsewhere in the engine, and the cracked blade is simply the symptom of a upstream fault. :8

I think one clue is in the news item. They need to ensure the support of the other nations involved in the development programme. They cannot afford to press on an risk another failure, so better to ground the fleet when such grounding in not yet an operational issue.

Look also at the 787 which has been grounded by the FAA. Then think of the Comet where they pressed on an lost more aircraft.

The RAF has been known to have tech groundings just they never publicised them to this extent. There was on grounding on the Vulcan fleet circa '65-'67 which lasted IIRC 10 days or more. As this did not prevent launch on deterrent missions, and we didn't wish to alarm anyone, it was kept Secret. the same was true of the Valiant force in '64. They remained operational yet grounded at the same time.

Does anyone here think we'll ever build the perfect engine that never fails, never catches fire, never gets upset? Is this the first engine that ever had a blade failure? Is this anything to do with the rest of the platform?

Come on. Wait and see before we judge. They have, after all, built a lot of good engines before, so probably know what they're doing. Above all, the engine isn't the biggest concern in the whole system.

Imagine the widespread panic if civilian airliners ever suffered turbine blade failures.

Luckily, civilian airliners have two engines, some even have four. The F-35 has one and if you have to shut it down, you have none. That is the difference.

Reports so far indicate the aircraft with the engine issue was from Edwards. Has it been reported which aircraft was involved as that's also the location of the high alpha test aircraft.

As turbine failures are generally considered uncontainable this must be considered a serious event. As was the case with the a380 trent engine a few years ago issues upstream can be a cause, so as was mentioned above sending the entire engine back to Pratt would be prudent.

Lucky for us we have the F136 as an option. Oh wait we don't............

Are you saying the problem is a permanent show-stopper then?

I don't think it is a permanent show-stopper, but one where a time-out is required to determine the scope of the problem. It could be unique to one turbine blade where an undetected, but should have been detected, defect was the source, or it could be a more general defect/material problem which could involve multiple blades. Unlike what some articles report, the turbine consists of a one stage high pressure turbine and a two stage low pressure turbine. Even if this is a stage 2 LPT blade, its failure could cause significant damage aft in the A/B as blade sizes and weights have gotten larger with fewer blades per rotor. So I think they did the correct thing until the true cause can be ascertained. It is unusual for a LPT turbine blade with low operating hours to develop detectable cracking.

TD

That's one BIG crash site.

TD - Thank you for your clarification.

"Mildenhall Royal Air Force, Middle Wallop, Hampshire, UK near Farnborough"
IIRC that was the climb-out from Farnborough one. The local kids were rewarded per lump retrieved, until it was realised that the enterprising little angels were breaking bits up in to many smaller lumps before handing them in.