Rolls-Royce believes the number of aircraft withdrawn from operations over Trent engine issues is starting to decline, without reaching the manufacturer's peak estimate of 50.
Chief executive Warren East detailed the manufacturer's progress on addressing the problems, focused on Trent 1000 blades for Boeing 787s, during an investor briefing on 15 June.
"We'd anticipated a pretty grim situation with aircraft on the ground," says East.
The company ramped up its maintenance capacity in response and trimmed the cycle time for inspections and parts replacement.
East says that the "bottleneck has shifted" from MRO capacity to logistics, given the time required for transporting large and heavy items.
He stresses that the aircraft-on-ground figure is "less than we feared", adding that it "never actually hit 50", and he puts the current level at 44 and falling.
Rolls-Royce has completed the first stage of initial inspections on the Package C version of the Trent 1000. East says the failure rate on repetitive inspections has been better than forecast.
But he also acknowledges that the situation is "causing a number of our customers a huge amount of disruption".
The company has embarked on a one-off inspection regime for Package B engines, to gather data.
East says that the "good news" is that these powerplants are affected "much later" in their life cycle, adding: "It happens after scheduled maintenance in the main."
Testing of a new Package C compressor rotor design is "going well", says East, and the company is still hoping to bring the implementation of a fix forward to this year, rather than early 2019.
East says turbine blade capacity is a "limiting factor" for the company but that it is continuing to improve the situation. Rolls-Royce has increased blade capacity by 50% since the beginning of the year.