KARACHI, Dec 2: Over four hundred passengers of a PIA flight went through a nightmarish situation at Karachi airport on Sunday as they remained trapped for two hours in an aeroplane after it failed to take off due to a fault in its engine.

Some of the passengers fainted and others panicked when they saw a spark in the engine, according to sources.

The Chief Justice of Pakistan, some federal ministers and a number of lawmakers were among the passengers of the Islamabad-bound flight PK-308.

All passengers had to return to the terminal because of the mishap.

After the fault was removed, the plane left for the federal capital at 8pm, four hours behind schedule. Nineteen of the passengers did not board the flight as some of them had already boarded another plane while others dropped their travel plan altogether.

The chief justice and some other passengers were accommodated on another PIA flight (PK 370), which took off at 7pm.

Sources said some of the passengers of the Boeing 747 Jumbo had fainted due to suffocation caused by extremely low levels of air-conditioning for a long period.

Air-conditioning in aircraft is usually lowered when the engines are started. As the engines of the aircraft failed to start, the period of low air-conditioning stretched beyond the passengers’ tolerance.

Besides, some passengers saw sparks in the engines, setting off a wave of panic, the sources said.

They said when the pilot switched on the engines, three of them responded, but the fourth failed to do so due to a fault in its starter valve.

The plane returned to the terminal and passengers were brought to the lounge.

Sultan Hassan, a spokesperson for PIA, denied that any passenger had fainted or there was any fire.

Syed Irfan Raza adds from Islamabad: Defence Minister Syed Naveed Qamar has convened a meeting on Monday to discuss the mishap.

The ministry of defence, however, has not ordered any inquiry.

“No inquiry has so far been ordered but a special meeting has been convened by the minister on the issue,” Narita Farhan, spokesperson of the ministry, told Dawn.

She rejected media reports that fire and smoke had threatened the cabin and some passengers had fallen unconscious. “It was a minor incident and all the passengers remained safe,” she said.