Pilots of a crippled Qantas Airbus A380 superjumbo struggled with more than a dozen system errors after an engine blew apart on Nov 4 and landed the plane in Singapore with barely any runway to spare, an Australian investigation showed.

In fact, the plane may have been so badly damaged that the five pilots, with a combined 72,000 hours of flying experience, may have saved the day.

The aircraft would not have arrived safely in Singapore without the focused and effective action of the flight crew, Martin Dolan, the Australian Transport Safety Bureau's Chief Commissioner, said on Friday.

As the Rolls-Royce Trent 900 engine blew apart over Batam Island, Indonesia, minutes after take-off, fragments ripped though parts of the wing, puncturing fuel, hydraulic and electronic systems and leaving the plane with limited flight controls, the ATSB said in a report.

But the magnitude of the damage became clear only when the co-pilot walked through the cabin and a passenger, another pilot, showed him a picture from a camera mounted on the plane's tail and fed into the onboard entertainment system.

The picture showed the Airbus was leaving a trail of fluid behind -- most likely fuel and perhaps hydraulic fluid -- from a puncture through the wing.

As the plane lost fuel quickly, its center of gravity also started to shift, presenting another problem. But the crew could not shift fuel as required as it was not clear how badly the fuel system was damaged, the report said.

There were so many warnings, it took pilots 50 minutes just to complete the required responses before they could prepare the plane for landing.

The number of errors was such that computers calculating landing data could not handle them all. Pilots removed some options, hoping that would still be enough to make an accurate call.

With the plane coming in at 440 tons, about 50 tons heavier than its maximum landing weight, the computer eventually concluded it would stop with just 100 meters of runway to spare at Singapore's Changi Airport, the report said.

But 100 meters was enough for the crew and they opted to land instead of dumping fuel, which would further upset the plane's balance.

The A380 remained controllable as its prepared to land, but it lost many of its systems which controlled pitch, speed and braking, so pilots asked the cabin crew to prepare for an emergency evacuation as they risked a runway overrun, it said.

The Airbus stopped with just 150 meters of concrete left, brakes heated to 900 degrees Celsius and four blown tires.

In addition, it was gushing fuel and one of its engines refused to shut down for over two hours, until fire crews drowned it with foam.

Pilots eventually decided against evacuation and kept passengers on the plane for another hour as fire crews secured the A380.

(Editing by Ed Davies)