The ATSB has released a preliminary report detailing an engine malfunction incident during a Qantas A330 passenger flight between Los Angeles and Brisbane on 4 December 2024.
The preliminary report summarises evidence gathered so far in the ATSB’s ongoing investigation. It does not contain analysis or findings, which will be published at the conclusion of the investigation.
The preliminary report notes that, while the Airbus A330‑200 was cruising at about 34,000 ft after departing Los Angeles, the flight crew received a passenger report of sparks emanating from the right engine observed during the climb.
After conducting a number of checks and considering alternate airports, the flight crew opted for a return to Los Angeles, and descended the aircraft to 31,000 ft to reduce load on the engine.
By the time the aircraft reached this altitude, the intermittent sparks were observed to have stopped.
“Later, as the aircraft was descending to land in Los Angeles, three loud bangs were heard, and there was a right engine compressor stall indication,” ATSB Chief Commissioner Angus Mitchell said.
“In response, the flight crew operated the engine at idle for the rest of the descent and landing.”
A post-flight inspection of the right engine identified a missing high-pressure compressor blade that had separated at its root, another high-pressure compressor blade fractured about half-way up, and damage to the tips of several other blades.
A variable stator vane was also found to be out of alignment, and there was metal debris in the engine’s exhaust.
The aircraft was subsequently grounded, and the right engine replaced.
The preliminary report details that, on the aircraft’s previous flight into Los Angeles, the flight crew had observed a high N2* vibration advisory.
During the turnaround in Los Angeles, two maintenance engineers troubleshooted the N2 vibration issue, during which they observed particles in the right engine exhaust.
“The ATSB’s ongoing investigation is considering the communications between involved personnel during this troubleshooting, including communications between staff in Los Angeles and at the Qantas maintenance operation centre in Sydney,” Mr Mitchell said.
The troubleshooting culminated in the aircraft being released to service with its N2 vibration sensor inoperative in line with minimum equipment list (MEL) requirements, meaning N2 vibration readings were not available to the flight crew on the incident flight.
“Flight crew for the incident flight told the ATSB they were not aware that particles had been observed during the examination prior to their flight,” Mr Mitchell noted.
As well as the communications and maintenance during the turnaround in Los Angeles, the ATSB’s ongoing investigation will examine the recorded data, maintenance procedures and records, and the outcomes of the material failure analysis being conducted by GE Aerospace on relevant components of the engine.
A final report will be released at the conclusion of the investigation, including findings, and any identified safety issues.
“Should a critical safety issue be identified during the course of the investigation, the ATSB will notify relevant parties immediately so appropriate and timely safety action can be taken,” Mr Mitchell concluded.
* N2 refers to the rotational speed of a jet engine’s high-speed spool, which consists of the high-pressure compressor and the high‑pressure turbine connected by a concentric shaft.
Read the preliminary report: Engine malfunction involving Airbus A330‑202, VH‑EBQ, 1,370 km west-south-west of Los Angeles International Airport, United States of America, on 4 December 2024