Clogged engine overhaul shops and a fast-tracking of necessary inspections on higher-time PW1100G geared turbofans will drive turnaround times up to as many as 300 days and could ground 650 Airbus A320neos at one time early next year, Pratt & Whitney parent RTX disclosed Sept. 11.

The details were revealed as RTX, formerly Raytheon Technologies, laid out the specifics in Pratt’s fleet management plan related to parts with contaminated powder metal (PM). Some 3,000 engines, including PW1000Gs of all types and IAE V2500s, built from mid-2015-mid-2021, may have parts with the defect. Cracking from PM contamination has been found in high pressure turbine (HPT) stage 1 and stage 2 disks, or hubs, installed in the motors. Pratt is also inspecting some high pressure compressor (HPC) disks built at the same time, RTX revealed. Most of the affected engines are PW1100Gs found on A320neo-family aircraft.

Pratt, on its second quarter earnings call in July, announced that previous PW1100G parts inspection intervals, developed after the problem was first uncovered in 2020, were not aggressive enough to flag cracks that the contamination can cause. It said as many as 1,200 engines would need to be pulled in the next year, including up to 200 by Oct. 1. Some of the checks would overlap with scheduled shop visits, reducing unplanned disruptions and costs.

The revised figures lower the number of engines that need immediate attention but narrow the removal window. The result is higher costs for Pratt and its PW1000G partners as its already full overhaul network faces a wave of engines that require extensive work scopes.

“Since our call in July, we’ve now developed a holistic fleet management plan that ensures the continued safe operation of the fleet while balancing the impact to our customers,” RTX president and COO Chris Calio said.

Under the plan, Pratt will pull 600-700 engines in the next two years in addition to 500 or so already scheduled for overhauls. Most of the accelerated removals will come by “early 2024,” Calio said. This includes 137 that must be pulled by the end of September. Problem parts in this batch have never undergone a more extensive inspection Pratt developed to help flag PM “inclusions,” now used on both new parts and those coming in for inspections, Calio said.

Pratt is developing service bulletins that outline the plan. Its most recent bulletin, calling for the highest-risk engines to be pulled from service in September, was mandated by the FAA and other regulators.

Some engines will undergo more extensive overhauls than normally called for, including replacement of both HPT and HPC disks. This will contribute to extended turnaround times, Calio said.

“It makes sense to replace the compressor disk at the same time,” Calio said. “This is why the work scopes are heavier. It will ultimately give the engine a longer run and be the least disruptive to the operators in the long term.”

Part availability will determine how many engines get new disks.

Calio said the entire process will “take between roughly 250 and 300 days on average from when these engines are removed from wing until they are returned to an operator,” Calio said.

The accelerated engine removals on top of work to address long-running PW1000G durability issues will mean as many as 650 A320neos could be out of service during the problem’s peak in the first half of 2024, Calio said. Fleet groundings will “average” 350 at any given time through 2026, he added.

Both the HPT and HPC disks are now being inspected every 2,800-3,800 cycles, depending on engine thrust ratings. The parts under scrutiny have a new, reduced life limit of 5,000-7,000 cycles. 

Pratt has no plans to divert spare engines from its pool of planned deliveries to Airbus, which is ramping up A320neo production, Calio said. If more spare engines come, it will be from an overall boost in PW1100G output, he suggested.

“The best thing that we can do to help operators is, yes, continue to produce the spare engines that are in the plan and try to ramp that to the extent that we can, but [also] driving the industrial ramp needed for MRO output,” Calio said.

While the PM inclusion issues pose enough risk to ground aircraft for inspections, they have not been linked to any A320neo in-service incidents. An Air China A320neo built in 2018 made an emergency landing in Singapore Sept. 10 with an apparent engine problem. Calio said Pratt is supporting the Civil Aviation Authority of Singapore-led investigation to determine the issue’s root cause, but “the current assessment is that we don’t believe it’s related to powdered metal.”

Pratt was working to add PW1000 overhaul capacity to help address the engine’s durability issues before the severity of the HPT disk problem became clear. It said in April it had 12 shops globally that could handle PW1000 work and planned to add seven more by 2025. Timelines for opening these new shops are being accelerated where possible to help offset the ramifications of the PM issue.

Monetary Hit

The fleet management program will cost Pratt and its PW1000G program’s partners $6 billion-$7 billion, RTX estimates. The charges, which will cover labor for inspection and customer compensation, include $3 billion-$3.5 billion for RTX, which plans to take a $3 billion charge this quarter to help reflect the costs. Customer compensation will account for 80% of the costs, with the rest covering shop-visit labor and materials.

RTX took a $500 million charge last quarter related to the issue, but executives cautioned then that they were still evaluating the problem’s scope and ramifications.

MTU Aero Engines, an 18% risk-sharing partner in the PW1000G program, said the expenses could reduce 2023 full-year revenue by €1 billion ($1.1 billion). “It is not possible at this stage to make a precise assessment of the impact on MTU’s forecast for the current financial year,” the company said. 

Estimates from other partners were not immediately available. 

Pratt’s detailed plan and financial ramifications do not cover the rest of the PW1000G family affected by the PM problem. Executives are confident, however, that any disruption to the affected Airbus A220 and Embraer E2 fleets will be minimal compared to what A320neo operators will face.

“We’ll have [a plan] in place for the PW1500 and PW1900 soon,” RTX CEO Greg Hayes said.

The Aviation Week Network Fleet Discovery database shows about 260 PW1500G-powered A220s and PW1900-powered E2s were built when PM-contaminated disks were produced. About 980 PW1100G-powered A320neos were built, as well as 450 V2500-powered A320ceo-family aircraft. 

Pratt has a plan in place for the V2500-powered fleet and is confident it is sufficient to detect any issues.