Qantas Flight 520

Qantas Flight 520

VH-VYH, the aircraft involved, photographed in 2022
Serious incident
Date	8 November 2024 (2024-11-08)
Summary	Contained engine failure during take-off caused by a turbine-blade fatigue crack
Site	Sydney Airport, New South Wales, Australia
Aircraft
Aircraft type	Boeing 737-838
Operator	Qantas
IATA flight No.	QF520
ICAO flight No.	QFA520
Call sign	QANTAS 520
Registration	VH-VYH
Flight origin	Sydney Airport
Destination	Brisbane Airport, Queensland, Australia
Occupants	181
Passengers	175
Crew	6
Fatalities	0
Injuries	0
Survivors	181

Qantas Flight 520 was a scheduled Australian domestic passenger flight from Sydney Airport to Brisbane Airport. On 8 November 2024, the Boeing 737-838 operating the flight, registered VH-VYH, suffered a contained failure of its right engine as it reached decision speed during take-off. The crew continued the take-off and returned to Sydney for a single-engine landing about 30 minutes later. All 175 passengers and six crew members were uninjured. Engine fragments ignited a grass fire beside the runway and disrupted operations at the airport.

The Australian Transport Safety Bureau (ATSB) classified the occurrence as a serious incident. Its final report found that a fatigue crack in a high-pressure turbine blade caused the blade to separate from the turbine disc, damaging the engine. It found that the flight crew had responded quickly and appropriately.

Aircraft and flight

The aircraft was a Boeing 737-838, serial number 34180, powered by two CFM56-7B24E engines. The flight carried two pilots, four cabin crew members and 175 passengers. The right engine had completed 17,656 flight cycles and was scheduled to be removed on 21 November, 13 days after the incident, as it approached the manufacturer's recommended removal threshold of 17,900 cycles. A borescope inspection on 25 September had found no significant defects, but this type of inspection could not examine the below-platform areas of the turbine blades where the fatigue crack developed.

Incident

The aircraft began its take-off roll on Sydney's runway 34R at 12:34:35 local time. At 12:35:20, as the first officer called the decision speed V₁, the pilots heard a loud bang and felt the aircraft shudder. The aircraft reached rotation speed three seconds later. Because the failure occurred at the decision speed, the crew continued the take-off and made a PAN PAN urgency call 28 seconds after lift-off.

Fragments expelled from the engine landed beside runway 34R and ignited a grass fire, closing that runway. The aircraft was slightly above its maximum landing weight and the crew selected the longer runway 34L for the return. While holding south of the airport, they completed the engine-failure checklists and asked an off-duty pilot travelling as a passenger to photograph the right engine. The photograph indicated that the failure had been contained and that there was no visible damage to the wing. Airservices Australia imposed a 47-minute ground stop, and delays at Sydney Airport averaged about 45 minutes.

The aircraft landed on runway 34L at 13:05:50. Airport firefighters inspected the engine before the aircraft taxied to the gate, where the occupants disembarked normally. No injuries were reported.

Investigation

The ATSB opened a limited-scope investigation. An examination by engine manufacturer CFM International found that two of the engine's 76 high-pressure turbine blades had separated below their platforms. Fatigue cracks in the dovetail of one blade caused it to separate from the disc; the adjacent blade then failed from tensile overstress. The remaining blades fractured from consequential overstress, and the debris caused a contained engine failure.

The failure mechanism had previously been recorded in the CFM56-7B fleet. The manufacturer reviewed the fleet after the incident and determined that the blade configuration used in VH-VYH continued to meet its reliability targets and regulatory guidance, so it did not lower that configuration's recommended removal threshold. The ATSB's final report, released on 29 April 2026, identified the fatigue crack as the contributing factor and praised the crew's response at what it described as a critical point in the take-off.

Aftermath

Qantas returned VH-VYH to service after replacing its right engine. The airline also removed two other CFM56 engines earlier than scheduled as a precaution, while saying that no common fault had been identified.

See also

• Qantas Flight 32
• List of accidents and incidents involving the Boeing 737

External links

• ATSB investigation AO-2024-057