Multiple systems issues plagued the crew of the Qantas Airways Airbus A380, which was forced to make an emergency landing in Singapore on 4 November after an uncontained engine failure in a Rolls-Royce Trent 900 powerplant.
The Australian Transport Safety Bureau, in its preliminary report on the incident, says that there were five crew on board the aircraft which was bound for Sydney from Singapore. These were the captain, a first officer, a second officer, a second captain who was undergoing training as a check captain, and a supervising check captain who was overseeing the training of the check captain.
While maintaining a speed of 250kts in the climb and passing 7,000ft above sea level, the crew heard two "loud bangs". The captain selected altitude and heading hold on the autopilot control panel, and the first officer started his chronometer.
The captain expected the auto-thrust system to reduce power on the engines to maintain 250kts as the aircraft levelled off. But the auto-thrust system failed and he had to manually retard the thrust levers to control the speed.
The aircraft's Electronic Centralised Aircraft Monitor (ECAM) system then displayed a "overheat" warning in the No 2 engine turbine, and this was followed by multiple ECAM messages. The engine's thrust lever was pushed to "idle" and monitored for 30 seconds, and another warning came out for 1-2 seconds indicating a fire in the engine. The crew shut down the engine, and the ECAM then indicated that the powerplant had failed.
The crew did not get any display confirmation that two attempts to discharge fire extinguisher bottles had succeeded. The crew then decided to continue the engine failure procedure, which included initiating an automated process of fuel transfer from the aircraft's outer wing tanks to the inner tanks.
At this point, the engine display for the No 1 and 4 engines reverted to a degraded mode. The display for the No 3 engine indicated that the engine was operating in an alternate mode as a result of the crew initiating an ECAM procedure. During this time, the ECAM continued to display numerous other warnings and alerts to the crew. These were:
• engines No 1 and 4 operating in a degraded mode
• GREEN hydraulic system - low system pressure and low fluid level
• YELLOW hydraulic system - engine No 4 pump errors
• failure of the alternating current (AC) electrical No 1 and 2 bus systems
• flight controls operating in alternate law
• wing slats inoperative
• flight controls - ailerons partial control only
• flight controls - reduced spoiler control
• landing gear control and indicator warnings
• multiple brake system messages
• engine anti-ice and air data sensor messages
• multiple fuel system messages, including a fuel jettison fault
• centre of gravity messages
• auto-thrust and auto-land inoperative
• No 1 engine generator drive disconnected
• left wing pneumatic bleed leaks
• avionics system overheat.
The crew alerted Singapore air traffic control that they may need to make an emergency landing, and also requested that they be met by emergency vehicles.
As they prepared to return to Changi Airport, the crew decided not to initiate further fuel transfer in response to a number of the ECAM messages "as they were unsure of the integrity of the fuel system". The ECAM fuel jettison fault meant that they could not dump fuel, which was also leaking from the left wing. The crew also recalled an indication that the aircraft's satellite communications system had failed.
As they prepared to land, they became aware of the following issues: the 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 also indicated that they could not apply maximum braking until the nosewheel was on the runway.
Singapore ATC vectored the aircraft to a position 20nm (37 km) from the threshold of runway 20C and provided for a progressive descent to 4,000ft. The captain set the thrust levers for No 1 and 4 engines to provide symmetric thrust, and controlled the aircraft's speed with the thrust from the No 3 engine.
The autopilot disconnected several times during the early part of the approach as the speed fell to 1kt below the approach speed. The captain initially tried to reconnect the autopilot but, when it disconnected again at about 1,000ft, he chose to leave it disconnected and fly the aircraft manually.
The flight crew briefed the cabin crew to prepare the cabin for a possible runway overrun and evacuation. The aircraft touched down at 0346, the nosewheel touched down within about six seconds, and the captain began maximum braking and selected reverse thrust on the No 3 engine. The flight crew observed that the deceleration appeared to be 'slow' in the initial landing roll, but that with maximum braking and reverse thrust, the aircraft began to slow.
As the speed approached 60kt, the captain was confident that he would be able to stop in the remaining runway distance. The No 3 engine was gradually moved out of maximum reverse thrust, manual braking was continued and the aircraft came to a stop about 150m from the end of the runway.
The crew began to shut down the remaining engines and, when the final engine master switch was selected OFF, the aircraft's electrical system went into a configuration similar to the emergency electrical power mode.
There was, however, an indication that the left body landing gear brake temperature was indicating 900°C, and rising. The No 1 engine could not be shut down for almost two hours despite several attempts. Four of the wheels on the left body landing gear had deflated as well.
The passengers were disembarked through the Number two main deck forward door, about fifty five minutes after the aircraft touched down. The last passengers and crew disembarked one hour later.
A single door was selected so as to perform a headcount of passengers. Throughout the disembarkation the crew was stationed by the exits, ready to activate the emergency slides if necesseary.
Source: Air Transport Intelligence news
