Mumbai, Sept. 4: An Air India plane with 229 passengers and crew on board caught fire moments before take-off this morning after the airline provided the aircraft as replacement for one that had sprung a snag.

Air India struck a ground engineer off the roster within hours of the Riyadh-bound plane taxiing close to catastrophe two days after a helicopter carrying the Andhra Pradesh chief minister crashed.

The Boeing 747-400, with 213 passengers and 16 crew members, was beginning to taxi for take-off when passengers sitting on the left side detected sparks flying out of the wing.

Flight AI-829 was grounded and the passengers were evacuated through emergency exit chutes on the right side of the plane. All the crew members were safe.

Black smoke billowed out of the engine even as the passengers were being evacuated. Four fire engines took two hours to douse the blaze, suspected to have been caused by a fuel leak.

“It was a jinxed flight to begin with,” said an Air India source.

The original plane, scheduled to leave at 2am, had developed a technical snag, forcing the flight to be rescheduled to 10.30am with the 1993 vintage leased aircraft drafted in as replacement.

An airline spokesperson said: “Due to delay in ATC (air traffic control) clearance, the flight was finally ready to take off around 1050 hours when the incident happened.”

Two versions about who spotted the fire came out of the airline. “The passengers told the cabin crew and the pilot contacted ATC and immediately grounded the flight,” said an official.

Jitendra Bhargava, the airline’s official spokesperson, however, said the ground staff had alerted the pilot.

Mumbai International Airport Ltd reported that several passengers had sustained minor scratches and bruises that required treatment.

“At least 21 people were injured in the scurry to exit and while slipping down the chute. But there was nothing major. They were let off after being given first aid,” said Manish Kalghatgi, a spokesperson.

The passengers left for Riyadh around 6pm by another plane.The AI official said: “Initial fact-finding has revealed that there was a small leak in the fuel tank. The fuel dripping on the heated engine on the left side set off sparks which later turned into a big fire. It could have led to a major catastrophe.”

Independent aviation expert Vipul Saxena said: “The plane had just begun to taxi… (and) the engine, though very hot by any standard, was not as hot as it would have been had the pilot gone full throttle during take-off. It would have led to a calamity then.”

Captain Mohan Ranganathan, an ex-Air India pilot, however, said: “Nowhere in the world in the entire history of global aviation has such a situation led to any disaster. A Boeing 747 is fully equipped to handle such a situation.”