PW1000G Groundings Continue To Rise As Latest FAA Mandate Takes Effect

The number of Pratt & Whitney PW1000G geared turbofan-powered aircraft on the ground continues to edge upwards as operators address required inspections linked to production problems, Aviation Week data shows.

Operators had about 670 PW1000G-powered aircraft on the ground at the beginning of April, up from 625 on March 1 and 580 on Feb. 1. Not all idled aircraft are sidelined due to the engine checks that target parts made with possibly contaminated powder metal (PM). Some are undergoing durability upgrades that predate the PM inspections. Others, such as 49 aircraft from insolvent Go Air that have been in storage for nearly a year, are grounded for operator-related reasons.

But the steady upward trend in parked aircraft that began in August 2023 is a direct result of Pratt’s plan to ensure thousands of parts on hundreds of engines are inspected and eventually removed based on revised life limit calculations.

Inspections targeting high-time parts, backed by FAA airworthiness directives (ADs) adopted by other regulators, began in September 2023. Pratt’s original projections saw related groundings peaking at 650 aircraft sometime in the first half of 2024.

Pratt parent RTX revised its outlook, pulling down the maximum number of grounded aircraft and projecting the peak would occur in the first quarter of 2024.

But the timing of the most recent AD, issued in late March and effective April 11 but based on Pratt service bulletins (SBs) issued in late 2023, means the peak grounding period has likely shifted into the current quarter. Some operators were waiting for the FAA to finalize the directive and related inspection intervals and life limits before committing to checks. The latest directive also incorporates parts not listed in the initial mandates but included in the latest Pratt bulletins.

While the peak number of aircraft groundings remains fluid, the expected average number of about 350 on any given day through 2026, when the bulk of the inspections are expected to be done, remains in play.

Pratt’s “fleet management plan” targets PM-contaminated life-limited parts (LLPs) made between Nov. 1, 2015, and Sept. 1, 2021. Parts affected are high pressure compressor (HPC) 7th and 8th integrally bladed rotors and aft disks, as well as high pressure turbine (HPT) stage 1 and 2 disks.

The 670 aircraft on the ground include about 320 that have been down for at least 90 days, according to the Aviation Week Network Fleet Discovery database. Another 300 have been parked for 30-90 days. Airframes on the ground for at least 30 days include 530 Airbus A320neo-family units, 70 A220s, and 17 Embraer E190s.

While some of the checks fall into scheduled maintenance intervals, hundreds of them are being accelerated, creating capacity and parts availability issues. Per-engine wing-to-wing turnaround times are around 300 days in most cases, industry sources said. About half of that time is waiting for an available slot in an overhaul shop.

Once an engine is in a shop, material availability becomes the pace-setting issue.

Pratt is working to get more capacity online as quickly as possible, and shops are exploring ways to reduce overhaul times. Pratt also has begun delivering full-life parts made after November 2021 to overhaul shops for installation on in-service engines.

Supply-chain lead times mean that parts with suspected PM issues made before November 2021 were still flowing into new engines on Pratt’s assembly line until late 2023. With the production line now covered, full-life parts began flowing into the overhaul network.

“We are starting to insert those parts into certain visits, and that’s going to ramp throughout the year,” Pratt President Chris Calio said at a mid-February Barclays investor conference.

Pratt declined to comment on current grounding figures.