FAA to order CF34 inspections for corrosion following Challenger crash

The FAA’s proposed rule applies to all CF34-3s — more than 1,100 of the engines on US aircraft..

The Federal Aviation Administration plans to require operators to inspect GE Aerospace CF34 turbofans for corrosion after investigators recently cited it as contributing to a 2024 event involving a dual-engine failure.

An FAA proposed rule released on 30 April applies to 1,152 CF34-3s on US-registered aircraft. The engines power MHIRJ CRJ200 regional jets and Bombardier Challenger 600 business jets.

The 2024 event involved a Challenger losing both its CF34s as it approached Naples airport in Southwest Florida. The aircraft crashed on a highway, killing the two pilots.

Corrosion in the both engines’ airflow control systems caused near-simultaneous compressor stalls and loss of thrust, the US National Transportation Safety Board (NTSB) recently said.

The airflow control systems alter stator vane positions to control airflow through the high-pressure compressors (HPCs).

The FAA has now issued a proposed rule in response to what it calls “a dual-engine power loss event and consequent manufacturer investigation”.

The proposed rule does not cite the 2024 Challenger crash but says GE’s investigation “revealed corrosion in the HPC case affecting the variable geometry system”

“Corrosion in the HPC case variable vane spindle bores can result in restricted range of motion of the [variable geometry] system, which can lead to compressor instability at or below idle speeds and potential loss of engine thrust control,” the FAA says.

GE on 30 October 2025 published a service bulletin addressing the risk. It calls on operators to complete CF34 start tests and HPC case borescope inspections.

The FAA’s proposed rule would require operators to complete those inspections on some CF34s before further flight; other engines would need inspections within one or two years.

The proposal would also mandate that operators complete restart tests on some of the turbofans every three months.

GE does not immediately comment.