'Mayday': Rare event on Aussie flight

ALL had seemed normal when a packed AirAsia passenger plane started rolling down the runway at Gold Coast Airport.

However, within moments of the Airbus A330’s wheels lifting off the tarmac, the late-night flight on July 3 last year was hit with a rare event, and new details have emerged highlighting just how serious it was.

First, one of flight D7207’s engines began experiencing vibrations at around 2300 feet (0.7km), then loud banging noises could be heard on-board, signalling an engine stall.

The crew called air traffic control and were then hit with an engine failure alert. As they continued to climb to 4000ft (1.2km), they received a call from a flight attendant on board who advised of a “starboard engine fire”, which could be seen from the aircraft cabin.

The flames had first been spotted by one of the company’s pilots who was travelling as a passenger. The crew took action, including discharging the fire suppression system.

Next came the distress call.

According to a new investigative report by the Australian Transport Safety Bureau (ATSB): “The flight crew upgraded the distress phase to a mayday with air traffic control and requested a diversion and approach to runway 01 at Brisbane Airport for an overweight, single engine landing.”

The aircraft, which had taken off at 10.49pm local time landed safely 20 minutes later in Brisbane. There were 359 people on board.

Bird remains and engine debris were later found on the runway at Gold Coast Airport. Footage taken of the runway showed flashes of flames coming from the engine during the takeoff roll, which occurred near where the debris was found.

The bird was identified as a masked lapwing, which are usually around 30-37cm long and around 0.23-0.40kg. These images released by the ATSB show the incredible damage done by the tiny creature.

What makes this case unusual is that most birdstrikes involving large aircraft do not result in damage (about 95 per cent), according to the ATSB. About 10 per cent of birdstrikes involving aircraft with turbofan engines result in the bird being ingested into an engine.

Engineers who examined the plane at Brisbane Airport discovered that a single fan blade-tip section, approximately 140mm by 125mm, had fractured from a fan blade and the fan rear seal was broken into pieces and scattered throughout the bypass areas of the engine. There was also evidence of fire within the engine.

It was shipped to Hong Kong for further investigation where debris from multiple masked lapwing birds were found on the fan, but evidence suggested a single bird had hit the blade itself.

The engine manufacturer, Rolls Royce, concluded that the loss of material from the blade had caused it to run out of balance, which led to high vibrations releasing the fan rear seal — which then broke up and fragments entered the core of the engine.

This ended up causing significant damage to the compressors, resulting in the compressor stalls. Oil also leaked, igniting in the engine.

The ATSB concluded: “Although aircraft engines are designed to withstand most types of birdstrikes — including those involving medium-sized birds such as a masked lapwing — this event appeared to involve a rare scenario comprising a combination of aircraft and engine speeds, the height of the fan blade at which the birdstrike occurred, and its angle of incidence.

“It is extremely unlikely such a scenario would occur on multiple engines simultaneously.”

AirAsia spokesperson Kris Taute said the airline welcomed the report, which followed a 10-month investigation.

“The report underlines the calm, skilful actions of the crew of AirAsia X Flight D7207 in diverting and landing the plane and its guests safely in Brisbane,” he said.

“This was an unprecedented incident and, as the report confirms, the crew were well-trained and prepared to manage this rare and unexpected situation. Safety at AirAsia has always been our number one priority.”

Let's block ads! (Why?)

Bagikan Berita Ini