The Federal Aviation Administration issued an airworthiness directive requiring airlines to replace some high-pressure turbine (HPT) disks in Pratt & Whitney PW1100G turbofan engines, relating the components to some parts that failed on an International Aero Engines V2500 unit in a 2020 incident.
The PW1000G is a high-bypass geared turbofan engine powering the Airbus A220 and A320neo aircraft, as well as the Embraer E-Jet E2 series. It’s also selected for installation in aircraft produced by Mitsubishi Aircraft Corp. and Russia’s United Aircraft Corp.
“The FAA considers removal of certain HPT first-stage and HPT second-stage disks to be an urgent safety issue,” according to the agency, as reported by FlightGlobal. “These HPT disks have the highest risk of failure and require removal within 30 days… This unsafe condition may result in loss of the airplane.”
Pratt & Whitney produces the turbine disks as part of its role in the IAE consortium. Disks installed in Pratt’s PW1100G units are made from a similar material.
The 2020 incident involved an “uncontained HPT first-stage disk failure that resulted in high-energy debris penetrating the engine cowling,” according to FAA and quoted in the online report. “Pratt & Whitney determined that the failure… was due to an undetected subsurface material defect in an HPT disk.”
Reportedly, Pratt & Whitney reviewed all of its own and IAE models that incorporate the similar parts, identifying 55 PW1100G engines installed in aircraft worldwide requiring the replacement disks.
The FAA’s airworthiness directive requires U.S. airlines to replace the affected parts within 30 days.
