New technologies will always have teething problems and one hopes PW gets their act together. For advancement and technology sake.
Which leads me to more questions, RR Ultrafan is even more complicated than this with movable fan blades, will RR get it right? There must be a reason GE has passed on this tech for now, even for the upcoming 797, is this tech not mature yet for jet engines (been used for decades in turboprops)?
The odd thing is that all these issues on the GTF appear to be related to the non gear (ie traditional) parts so should be well known. The killer for the GTF will be if the gear starts to have issues.
That's not exactly unrelated, I've made similar claims as william in the past.
For example take the shaft bend/bow. The shaft is directly connected to the sungear system, so it's part of the gear system.
What could be the variables versus non-GTF designs? Higher shaft RPM's of the GTF system and higher torque requirements.
Similarily, the bearing seal issue could be attributed to higher shaft RPM resulting in various issues.
For the high pressure compressor seal, what could be the variables versus non-GTF or previous designs?
It could be a higher overall pressure ratio of the GTF architecture putting unexpexted high strain on an assembly that was lazily copy-pasted from previous designs.
We can't know for sure, but we do know that there is a serious issue there.
A GTF engine is not a reliable/sustainable GTF engine until all variables have been accounted for.
Everyone says that the GTF engine has more margin for growth. That's an easy thing to say, but it doesn't make it true until we compare the final architecture of a GTF engine that is as reliable as an organically improved CFM Leap. If after all the issues are fixed, the PW1100G is finally as reliable as the CFM Leap but ends up with a fuel burn equivalent to the CFM56 due to the modifications scraping off the GTF fuel burn advantage little by little, then the gear technology would have to be written off as an unnecessary piece of technology...
http://atwonline.com/engines/easa-issue ... -directive
EASA said aircraft with two affected engines can only operate three more cycles. It is also ordering extended-range, twin-engine operations (ETOPS) limitations. Airbus has issued an Alert Operators Transmission (AOT) providing instructions “to de-pair the affected engines and discontinue [ETOPS] for aircraft fitted with affected engines,” according to EASA.
EASA said the batch of affected engines begins with serial number P770450, but neither the aircraft manufacturer nor the agency disclosed what airlines are operating aircraft with affected engines.
I find it weird that as big a company as UTC is struggling with all of these separate things. It proves that the engine was not mature at certification.
As for CFM and the Leap, I think that they have delivery delays of their own and it's not like they could increase production rates overnight.
Airbus has several options if the delay is expected to be long. They could revert to producing CEO's to the benefit of IAE and CFM, or invest in the ramp up the Cseries which seems surprisingly unaffected by the issues and could be offered as interim lift until the NEO's are reliable enough.
The latter would also help PW, which could move resources from the PW1100G to build more PW1500G's until the issues are all fixed.
Last edited by Waterbomber
on Sat Feb 10, 2018 11:18 pm, edited 1 time in total.