A number of years back I was asked if I could go source a couple of tonnes a year of yttrium oxide. Didn’t work out but I was asked – it was to make the engine coating for a new and large jet fighter development program:
The heat coating on the engine’s rotor blades is failing at a rate that leaves 5 to 6 percent of the F-35 fleet parked on the tarmac at any given time, awaiting not just engine repairs, but total replacement.
Guess they didn’t find a decent supplier then.
Engine repairs? What, on the airframe, in the mount? Far easier to remove it, just a couple of bolts and pipes and some electrics, and let the factory do the fixing while you fit another you got back from fixing. And only 5% down for it? That’s pretty good in the early years of deployment.
Two possibilities here really: either the engine is being run at a higher duty cycle than expected or the design of the engine was deficient. Given the F35 is early in it’s career, the second is more likely, especially since the vertical landing capabilities are what really drove the engine requirements. It’s usually the “hot end” turbine which has the issues first as this is usually the most stressed component, and although coatings are nice and all, the biggest driver these days is the active cooling system used to make unfeasibly high TIT’s practical. So, mostly not your fault, Tim 🙂
For context, in the early years of the F-15 Eagle, it was a really good day if 50% of the fleet was airworthy on any given day, and the F-16 got the nickname “Lawn Dart” because so many of them were falling out of the sky.
Both initial service-entry problems long ago fixed, and forgotten by those who are claiming the F-35 is the Worst! Aircraft! Ever!.
I’ve always had a soft spot for ceramic coatings: a quarter-century ago I managed to save the taxpayer a useful bit of money by replacing epoxy paint with plasma-sprayed alumina, which (long story short) stopped a torpedo battery fire from trashing the whole torpedo and usually kept the expensive electronics fit to reuse.
Guess they might be regretting canning the GE/Rolls-Royce Fighter Engine Team alternative engine programme then…
I remember the F-104 “Widowmaker”. But the F-35 might well be worse. Hell, even if it worked as designed it might well be worse, being a horse designed by a committee.
Whereas the F-104 had a designer who was best known for his specialist-purpose designs. Of which the F-104 was one until NATO’s money came along to corrupt it. It’s unlikely that the F-35 will ever match the accident records of the 50s and 60s.
I hadn’t read the linked article. It is such bollocks in the assertions that I am a little informed on that I assume it is all bollocks. I suggest nobody goes to SALON for military procurement stories. There seems to be just a teeeeeeny bit of bias there.
The next war will be economic: China will threaten, USA will present some F35, and China will bankrupt USA by shooting them down at $150m a time. They can keep that up for years.
And of course, to build replacements, all the rare earths for new F35-Dodo’s have to come from…..China!
Pooh bear laughs his head off.
On similar topic, the UK F35s were to be serviced in Turkey. Since Turkey puckered up to Russia and bought their AA system, Turkey is now off limits to F35. So where will the RAF have them serviced?
The whole idea of getting into a plane needing servicing, and flying it 1000 miles, and landing in a hostile nation for repair work, may need some rethinking perhaps.
@rhoda klapp
Never mind the Salon article, which is long on assertion and short on facts.
But its right in essence, the F35 is a scandal, a turkey, totally unfit for purpose. There’s an interesting book by David Archibald arguing that a licence to manufacture Saab Gripen would be far more useful, far cheaper, and actually work. That is full of source material to justify his argument.
Oh, and if you fire the gun, the gun mounting breaks.
you didn’t try ebay, Tim?
https://www.ebay.co.uk/itm/Yttrium-III-oxide-99-9-100-Grams/293994181579?hash=item44736b33cb:g:GdsAAOSwXbNgHPP6
From Lithuania, even at this retail price would cost only a quarter of a million, peanuts in context. Might be cheaper from US or China or any of these vendors
https://pubchem.ncbi.nlm.nih.gov/compound/Yttrium-oxide#section=Chemical-Vendors
but I’m not sure there’s a shortage.
I can’t see the advantage of it as just a coating, however thermodynamically stable it is.