An investigation was under way tonight after a London to Sydney superjumbo with 433 passengers on board made an emergency landing after flames were seen pouring from one of its engines.
Frightened passengers spoke of debris from one of the four Rolls-Royce engines piercing the wing of the Airbus A380, the world's biggest aircraft, operated by Australian airline Qantas.
It is the first major safety incident involving the 555-seater double-decker plane which made its first commercial flight in October 2007.
Passenger Lars Sandberg, a DJ from Glasgow, said he was "just happy to be alive" after the plane landed safely back at Singapore airport.
Others on the flight said passengers were shouting and crying with relief when the plane touched down safely.
Rolls-Royce Trent 900 engines powered the Qantas plane and a company spokesman said tonight that a "number of basic precautionary engine checks" were being made.
He added: "We will continue to work closely with our customers as the investigation moves forward. This is at a very early stage and it would be inappropriate to draw any conclusions at this time."
Qantas has grounded its six Airbus A380s but other operators of the giant plane are carrying on with their A380 flights.
Images taken of the jet after the emergency landing revealed that one of its giant engines has been badly damaged.
The front half of the engine appeared intact but the rear half was charred and burned with the metal work exposed.
The wings of the plane were made in Britain by Airbus UK at Broughton in North Wales.
French air accident investigators said it was thought that a section of engine cover had fallen off, adding that it was "a serious incident".
Toulouse-based Airbus has joined Qantas, as well as Australian and European air safety bodies in an investigation into the incident which is being led by authorities in Singapore.
As the investigation continued, the Australian Licensed Aircraft Engineers Association said safety was a growing concern for engineers at Qantas as outsourcing of work continued.
Association spokesman Steve Purvinas added: "It's about time Qantas listened to the warning signs."
Today's incident happened just after the plane, QF32 with 26 crew aboard, had taken off from Singapore to Sydney on the last leg of the flight from London.
One passenger, Singapore-based businessman Ulf Waschbusch, said: "About five minutes after take off from Singapore I heard a loud boom noise on my left hand side so I immediately look out of the window at that point.
"I saw pieces of the engine, number 3 engine, fly off the wing through the wings itself and short bursts of flames for about a second or two at that time.
"It was one of the scariest things I have ever seen on an aircraft."
Mr Waschbusch said that after the landing back at Singapore there was "immediately rapture, shouting and crying".
Mr Sandberg said: "Everything was going smoothly in the first 15 minutes and then there was a sharp bang. I thought some metal container fell down in the cargo area, but the carriage started to vibrate and there was a bit of smoke.
"I was sitting right next to engine two. People around me were visibly shaken and we all realised that whatever happened wasn't normal. There was a mother with two children who was quite worried."
He went on: "The landing was quite smooth, although the plane felt a bit heavy. When we landed there was fuel leaking from the plane, something ignited and blew the case of the engine.
"When we got off and saw the engine itself and the back casing burnt off, that was pretty scary. It was a nerve-wracking experience and I feel a little bit shaken up. I'm just happy to be alive and safe in the terminal building."
Another passenger, Matt Hewitt from Cheshire, said some people on board had seen bits of a wing "breaking up" with "parts sticking up and wires hanging out".
He added that he had been "a bit frightened" but that he would certainly fly with Qantas again.
Mr Purvinas said: "We know that the dramatic increase in the number of safety incidents involving Qantas jets coincides with an increase in the amount of work that is no longer carried out in-house."
He said the airline was "naive" for believing the current number of maintenance engineers could maintain its fleet of A380s.
Singapore Airlines has 11 superjumbos, with Emirates having 13, Qantas six, Air France four and German carrier Lufthansa three.
British Airways has 12 A380s on order, with deliveries due to start in 2013. Sir Richard Branson's airline Virgin Atlantic has six on order which are due to be delivered in 2015.