Islamabad/New Delhi, July 9: A Delhi-bound Air India flight was forced into an emergency landing at a Pakistani airport early this morning, apparently because a computer glitch set off a “false alarm” mid-air about a hydraulic system failure.

The 122 passengers of the Airbus A319 from Abu Dhabi reached Delhi at 5.45pm, on a relief aircraft sent from India, after being accorded “state guest” status in the neighbouring country.

AI 940 had landed at Sindh’s Nawabshah airport, 232km northeast of Karachi, at 3.27am local time after the cockpit panel emitted emergency signals, which airline sources later claimed were spurious.

South Block officials praised the way the Pakistanis “went out of their way” to help the stranded passengers. ( )

Although Pakistani authorities offered the use of the airport’s lounges, pilot Sunil Vashist preferred to have the passengers remain on board. On Vashist’s request, drinking water and beverages were supplied to the aircraft.

Pakistani officials said even food was arranged but it appears the pilot declined the offer. The passengers were later served food on the relief aircraft, an Airbus A320.

Jayshree Purohit, travelling with her 19-year-old son Akshay, said the A319 had no food left. “They served us tea in the morning and were very nice and helpful.”

Muskan Sharma, 15, said she was “scared” when the pilot announced the snag.

The computer signals had suggested that each of the plane’s three hydraulic systems had failed — deemed such a rare occurrence that pilots usually train to deal with the failure of up to two hydraulic systems.

“The three hydraulic systems — two main and a back-up — are critical for virtually every key system of the plane: its landing gear, steering and brakes. If the main systems overheat, the back-up steps in,” an Air India official said.

The Directorate-General of Civil Aviation, which is probing the matter, said it was too early to say whether the alarm was a false one.

Air India engineers flown to Nawabshah by the relief plane repaired the snag in the A319, which arrived in Delhi late in the evening.

Sources said it had been decades since an Air India commercial flight had landed on Pakistani soil. Pakistan’s national carrier PIA, though, operates a couple of flights to India.