Monday, December 06, 2010

Qantas Flight 32: Crew response to the emergency

by B. N. Sullivan

This is the third in a series of posts about Qantas Flight 32, an Airbus A380 (registration VH-OQA) that experienced an uncontained failure of one of its four Rolls-Royce Trent 900 engines during flight on November 4, 2010.  The information here is based on a preliminary report by the Australian Transport Safety Bureau (ATSB), issued On December 3, 2010.

As mentioned in the previous post, there were five flight crew on board Qantas Flight 32: the Captain (PIC); a First Officer (FO), acting as co-pilot; a Second Officer (SO); a second Captain, who was training as a Check Captain (CC); and a Supervising Check Captain (SCC), who was training the CC.  This post details how they responded to the emergency following the uncontained engine failure that damaged the aircraft and a number of its systems.

Early in the emergency, given that the aircraft was controllable, the crew decided to hold their present altitude while they processed the plethora of ECAM messages that immediately followed the engine failure.  [See previous post.]  They contacted Singapore ATC and asked for an appropriate holding position, ultimately requesting "to remain within 30 NM (56 km) of Changi Airport in case they should need to land quickly."  ATC vectored the aircraft into a holding pattern east of the airport  at 7,400 ft.

As the crew went through procedures associated with the ECAM messages, the SO went into the cabin to try to visually assess the damage to No 2 engine.
As the SO moved through the cabin a passenger, who was also a pilot for the operator, brought the SO’s attention to a view of the aircraft from the vertical fin mounted camera that was displayed on the aircraft’s in-flight entertainment system.  That display appeared to show some form of fluid leak from the left wing.
The SO then went to the left side of the aircraft's lower deck and observed the wing damage and fuel leak.  He saw a fuel trail about 0.5 m wide that appeared to be coming from underneath the wing.

Later, the SCC and SO returned to the cabin "on numerous occasions to visually assess the damage on the left side of the aircraft, and to inspect the right side of the aircraft, and to provide feedback to the cabin crew and passengers."

Meanwhile, up on the flight deck:
The flight crew reported that, during their assessment of subsequent multiple fuel system ECAM messages, they elected not to initiate further fuel transfer in response to a number of those messages, as they were unsure of the integrity of the fuel system.  In addition, the crew could not jettison fuel due to the ECAM fuel jettison fault and they were aware that there was fuel leaking from the left wing.  The crew also recalled an indication that the aircraft’s satellite communications system had failed.  They also received an aircraft communications and automatic reporting system (ACARS)message from the aircraft operator that indicated that multiple failure messages had been received by the operator from the aircraft.
It took about 50 minutes for the crew to complete procedures associated with the many ECAM messages.
They then assessed the aircraft systems to determine those that had been damaged, or that were operating in a degraded mode.  They considered that the status of each system had the potential to affect the calculation of the required parameters for the approach and landing.  The crew also believed that the failure may have damaged the No 1 engine, and they discussed a number of concerns in relation to the lateral and longitudinal fuel imbalances that had been indicated by the ECAM.
The FO and the SCC performed several calculations to determine the landing distance required for their overweight landing.  They determined that landing on Changi's runway 20C  "was feasible, with 100 m of runway remaining," and advised ATC to that effect.

Approach and Landing

Prior to leaving the holding pattern, the crew carried out a number of manual handling checks at holding speed to assess the controllability of the aircraft.
As the crew started to reconfigure the aircraft for the approach by lowering flaps, they conducted further controllability checks at the approach speed and decided that the aircraft remained controllable.  As a result of the landing gear-related ECAM messages, the landing gear was lowered using the emergency extension procedure and a further controllability check was conducted.

The landing performance application indicated a required approach speed of 166 kts.  The flight crew reported being aware that: reverse thrust was only available from the No 3 engine, no leading edge slats were available, there was limited aileron and spoiler control, anti-skid braking was restricted to the body landing gear only, there was limited nosewheel steering and that the nose was likely to pitch up on touchdown.  An ECAM message indicated that they could not apply maximum braking until the nosewheel was on the runway.  The wing flaps were extended to the No 3 position.

Singapore ATC vectored the aircraft to a position 20 NM (37 km) from the threshold of runway 20C and provided for a progressive descent to 4,000 ft.  The PIC was aware that accurate speed control on final would be important to avoid either an aerodynamic stall condition, or a runway overrun. Consequently, the PIC set the thrust levers for Nos 1 and 4 engines to provide symmetric thrust, and controlled the aircraft’s speed with the thrust from No 3 engine.

The autopilot disconnected a couple of times during the early part of the approach as the speed reduced to 1 kt below the approach speed.  The PIC initially acted to reconnect the autopilot but, when it disconnected again at about 1,000 ft, he elected to leave it disconnected and to fly the aircraft manually for the remainder of the approach.  Due to the limited landing margin available, the CC reminded the PIC that the landing would have to be conducted with no flare and that there would be a slightly higher nose attitude on touchdown.
Cabin crew were briefed to prepare the cabin for a possible runway overrun and emergency evacuation.

The aircraft touched down, the PIC applied maximum braking and selected reverse thrust on the No 3 engine.  The aircraft came to a stop with about 150 meters of runway remaining.

After Landing

The crew shut down the remaining engines, however the No 1 engine continued to run.  The crew recycled the engine master switch to OFF, but the engine still did not shut down.  The crew then tried using the emergency shutoff and fire extinguisher bottles to shut down No 1 engine, but to no avail.  Activating a series of circuit breakers in the aircraft's equipment bay, and efforts to starve the No 1 engine of fuel also were unsuccessful.  Ultimately, "the decision was taken to drown the engine with fire-fighting foam from the emergency services fire vehicles," but this did not happen until about 2 hours and 7 minutes after the aircraft landed!

Meanwhile, passengers disembarked on the right side of the aircraft via stairs.
The crew elected to use a single door so that the passengers could be accounted for as they left the aircraft and because they wanted the remainder of the right side of the aircraft to be kept clear in case of the need to deploy the escape slides. They also decided to have the other doors remain armed, with crew members in their positions at those doors ready to activate the escape slides if necessary, until all of the passengers were off the aircraft.
It took about an hour for all passengers and crew to leave the aircraft. There were no injuries reported among the five flight crew, 24 cabin crew and 440 passengers on board Qantas Flight 32.

[Photo Source]

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