MUMBAI: An Air India Jaipur-Mumbai flight flew well past its destination with both its pilots fatigued and fast asleep in the cockpit. When the pilots were finally woken up by anxious Mumbai air traffic controllers, the plane was about half way to Goa. ( Watch )

This nap in the sky took place about a fortnight ago on the domestic leg of a Dubai-Jaipur-Mumbai flight ��� IC 612 ��� which had about 100 passengers on board. "The plane took off from Dubai at 1.35am IST and then from Jaipur at 7am. After operating an overnight flight, fatigue levels peak, and so the pilots dozed off after taking off from Jaipur," said a source.

The flight schedules of pilots prior to this flight is not known.

The aircraft was supposed to take the A 474 South route ��� a designated route to Mumbai ��� and since it was on autopilot, it headed in that direction. "It was only after the aircraft reached Mumbai airspace that air traffic controllers realized it was not responding to any instructions and was carrying on on its own course," said the source.

Said an air traffic controller: "The aircraft should have begun its descent about 100 miles from Mumbai, but here it was still at cruising altitude. We checked for hijack and when there was no response we made a SELCAL (selective calling)."

Every aircraft has its own exclusive code. When the ATC uses this high frequency communication system ��� which it does very rarely and only when other communication draws a blank ��� a buzzer sounds in the cockpit. Jolted by the sound of the SELCAL buzzer, the pilots woke up and brought the plane back to Mumbai safely.

Kanu Gohain, directorate general of civil aviation, was not available for comment. Contacted for its version on Wednesday evening, Jitendra Bhargava, director, public relations of Air India, said, "The director, operations, is getting information on the matter."

'Aircraft had communications failure'

General manager, Mumbai aerodrome, M G Junghare, denied that the pilots were asleep behind the control column. "The aircraft had a radio communications failure and so could not be contacted. It had gone only 10 or 15 miles off Mumbai and after we ascertained that it was not hijacked we made the SELCAL," he said.

Commanders, however, pooh-poohed this claim and said the lapse was being hushed up. "There is a strict procedure which is followed during a radio communications failure whereby the aircraft should have descended to a holding point. Instead, it flew over Mumbai. Also, every flight has an Expected Time of Arrival (ETA), so why did it not begin its descent even after crossing its ETA?" argued a check pilot.

For the last one month, airlines have been following an old set of pilot rest rules that has no scientific backing. This happened after DGCA issued a circular in May asking airlines to the old and outdated Flight Duty Time Limitation that essentially lengthened flight duty hours. DGCA withdrew the new timing schedule introduced in July last year and which was based on scientific studies by Nasa. The pilots protested this. A Joint Action Committee of Airlines Pilots' Association has recently moved the Bombay HC to quash the DGCA circular stating that shorter breaks between long-haul flights and even ultra-long haul flights could compromise safety.

"If you get home past midnight and then by noon the next day you are in a car back to the airport, and if this happens every other day and you do not even know your weekly off in advance, the buildup of exhaustion is huge," said a commander. The latest incident, an index of fatigue in the skies, could strengthen the pilots' case. "Had the aircraft flown over Hyderabad they would not have been able to contact the pilots since SELCAL is available only at old airports like Mumbai and Chennai since it is an obsolete technology and not used in newer airports. Moreover, a SELCAL cannot be made in certain weather conditions," the commander said.

A similar incident in the US in February suggests that pilots don't have it easy there either. The difference is that the US authorities were not only open about it, but initiated corrective measures. Two 'go!' airline pilots fell asleep while flying from Honolulu to Hilo, cruising past their destination for 18 minutes before waking up and returning safely. The two pilots had been flying for three arduous days. Following the incident, the US's National Transportation Safety Board highlighted the need for new rules. It recommended working hour limits for flight crews, aviation mechanics, and air traffic controllers based on fatigue research.

