The Federal Aviation Administration (FAA) has issued a new airworthiness directive (AD) for certain International Aero Engines, LLC (IAE), Pratt & Whitney (PW) 1100G-JM engines.

PW 1100G-JM is a high-bypass geared turbofan engine family; developed under IAE LLC, a consortium of Pratt & Whitney, the Japanese Aero Engines Corporation (JAEC) and MTU Aero Engines.

developed by Pratt & Whitney with participation from THEIR member companies, IAE LLC, MTU Aero Engines and JAEC.

This engine powers the Airbus A320neo family.

Lufthansa A320neo in Frankfurt (Photo by TJDarmstadt)

Previous Problems

In the previous AD, the FAA reported that since 2017 received 57 instances of fractures occurring on the low-pressure turbine (LPT) 3rd-stage blades. It appears that these failures were caused by impact damage, occurring when debris passed through the engine.

According to the FAA, the manufacturer has determined the need to replace any affected LPT 3rd-stage blades with LPT blades made of a different material; this being a material that is more resistant to impact damage.

PW 1100G Cutway (By Pratt & Whitney)

Required Actions

This AD requires the replacement of the affected LPT 3rd-stage blades, due to the previous failure reports. The FAA states that the AD is effective as of May 21st.

If not addressed, it could result in: the uncontained release of the LPT 3rd-stage blades, a failure of one or both engines and a loss of thrust control; consequentially this could lead to the loss of the aircraft.

The required actions must be done at the next engine shop visit, after the effective date of the AD. Any LPT 3rd-stage blades with P/N 5387343, 5387493, 5387473 or 5387503 must be removed from service and replaced with a part eligible for installation.

For the purpose of this AD, the FAA explains that an “engine shop visit” is the induction of an engine into the shop for maintenance involving the separation of pairs of major mating engine flanges.

For the replacement of a set of LPT 3rd-stage blades, the FAA estimates a part cost of $750,000 per blade set per engine.

This AD concerns the following turbofan engines: PW1133G-JM, PW1133GA-JM, PW1130G-JM, PW1129G-JM, PW1127G-JM, PW1127GA-JM, PW1127G1-JM, PW1124G-JM, PW1124G1-JM and PW1122G-JM.

Feature Image: Airbus