With regard to the glitch:
Pratt & Whitney said on Monday it expects to present a fix to European regulators this week for a problem with its new geared turbofan jet engine that halted deliveries of Airbus’ (AIR.PA) latest version of its most popular aircraft model.
Pratt said the latest problems were discovered in January and early February, and stem from an engineering change the company made last summer to the “knife-edge seal” in the high-pressure compressor near the rear of the engine.
Not sure what the time between presenting a fix and it being accepted and then retrofitted might be. Interesting to read about the time between introduction (last summer) and discovery (late Jan) suggests a fair bit of latency.
The glitch is exactly as I expected upthread: a change in the manufacturing process of one or more components that turns out to be faulty.
P&W does change some components from time to time, and apparently something went wrong here. Hence a selected batch of engines are not safe.
It also explains why the issue wasn't found during flight testing: it's a new component introduced years after flight testing.
And the numbers:
The numbers were already given in the opening post of this thread.
Fir what's it's worth, analysts are less concerned:
Pratt has delivered about 550 engines so far and said in January it aims to double output this year. “It seems reasonable to conclude that only 30 to 40 engines or 15 to 20 aircraft are affected at this point, which is a small number,” analyst Carter Copeland and Melius Research wrote in a note published Monday.
Clearly the scale is much smaller than the bearing seal and combustion chamber issues, which affected all engines.
Seems to be news that more engines are being evaluated, no?
These would be engines that have been delivered to Airbus, but not yet to the customers.
What we leave behind is not as important as how we've lived.