FAA Draft Rule Links PW2000 Parts To Powder Metal Issue

Pratt & Whitney’s powder metal part-contamination problem affects hundreds of PW2000 engines on Boeing 757s and C-17s that will require FAA-mandated inspections, but the projected ramifications are not nearly as operationally disruptive as similar issues on the PW1000G fleet.

A draft FAA airworthiness directive (AD) set for publication June 2, details the issue. The AD, based on Pratt service bulletins issued in 2024, calls for inspections of certain high-pressure turbine (HPT) first-stage disks and turbine hubs flagged as possibly having contaminated nickel powder metal (PM) introduced during production. The document also lists 15 specific parts by serial number—all HPT seals—that must be removed from service.

The inspections can be done at “piece-part exposures,” or when the affected engine section is disassembled during an overhaul, the directive said.

So far, part-life limits have not been affected, and inspection intervals have not been shortened, meaning that, unlike with PW1000G geared turbofan (GTF) parts with the same issues, unscheduled engine removals are not required to comply with the requirements.

“This AD is in line with previous service bulletins provided to operators and requires inspections of certain components originally provided as spares,” a Pratt spokesperson told Aviation Week. “The inspections will be conducted during scheduled overhauls. There are no new part life limitations, and no groundings will be required.”

It was not immediately clear how many inspections have been accomplished.

About 1,550 PW2000-series engines remain in service, all found on twin-engine 757s and four-engine C-17 military transports, the Aviation Week Network Fleet Discovery database shows. About 1,130 are with U.S operators.

The PW2000’s military designation is the F117. The PM issue affects 484 of the U.S. engines, the draft AD said. It does not detail the global fleet ramifications.

The U.S. Air Force (USAF), with 230 C-17s, and Delta Air Lines, with 106 757s, operate the largest affected fleets, Fleet Discovery shows. Delta’s youngest PW2000-powered 757s are 20 years old.

The USAF in February issued a request for proposed collaborations with industry to develop a new engine in the 30,000-50,000 lb. thrust range for use on a yet-to-be-developed mid-sized air transport and to reengine C-17s. “As the C-17 will remain a mainstay of the Air Force’s strategic airlift capabilities for at least the next three decades, a reengine or technology upgrade for the current F117 (PW2040) engines could provide value,” the project description said.

Neither Delta nor the USAF Life Cycle Management Center responded to an Aviation Week inquiry.

Contaminated PM parts are susceptible to hard-to-detect cracks that can grow quickly. Ensuring the parts don’t fail requires special inspections and, in some cases, shorter-than-expected inspection intervals.

Pratt discovered the contamination issue, which affects certain parts made from 2015 to 2021, as part of its probe into a 2020 engine failure on a Vietnam Airlines IAE V2500-powered Airbus A320. Pratt is a partner in IAE.

As Pratt broadened its review of production records and new-inspection data, it expanded the affected population of parts and engine types. The PW1000G family is seeing the most operational impact, with groundings of 300 or more A320neos and A220s through 2026 as operators await engines that are undergoing work.

Wing-to-wing turn times for the PW1000Gs are running at 250 days or more, mostly due to the limited number of shops that can perform the specialized inspections and a shortage of available spare parts. Other engine types are affected, including the V2500 and F135, which powers the Lockheed Martin F-35, though PM-related groundings have largely affected the PW1000G fleet.

PW2000 operators were informed early last year that some of their parts are part of the production runs with possibly contaminated PM. Pratt issued its recommended plan in May 2024. The draft AD is based on the OEM’s plan.

Meanwhile, the engine manufacturer’s efforts to minimize PW1000G operational disruptions linked to its PM fleet management plan continue to bear fruit. Off-wing times are slowly coming down thanks to an increase in spare-parts output, improvements in initial disassembly and post-work reassembly processes and some newly developed repairs, said Chris Calio, CEO of Pratt parent RTX.

“We’re seeing turnaround times come down,” Calio said at a recent Bernstein investor conference. “We’ve compressed it about 10%.”

Pratt’s initial projections in 2023 had turnaround times running at about 300 days—a figure that proved accurate. Aircraft on ground (AOG) figures peaked in early 2024 at around 650, mostly A320neos, and have settled in at about 300-350, where they are expected to remain until 2026.

Total cost of the unscheduled work, parts and related operator compensation is estimated at $6-7 billion for RTX and the GTF risk-sharing partners. “The technical and financial outlook that we put on the fleet management plan remains consistent,” Calio said.

Calio offered some hope that Pratt can reduce the AOG figure by getting engines moving through shops even more quickly.

“Repair development has been another focus for us, continuing to drive parts that were scrapped before, where you would need a new part, developing repairs to salvage that part better from a turnaround time perspective,” he said. “We need to continue to see material flow through our shops. When it does, our teams can compress turnaround time significantly on heavy work scopes. The teams are continuing to learn out our processes and get better at taking time out.”