Plane carrying 280 passengers plunges 5,000 feet after co-pilot 'fiddled with the controls' while captain was taking a nap

• e-mail

Investigators who are trying to determine why a passenger jet dropped more than 5,000 feet in Turkish airspace say the co-pilot ‘fiddled’ with aircraft controls.

The incident occurred while the captain of the Jet Airways Boeing 777-300 was taking a nap during a Mumbai-to-Brussels flight in August.

The co-pilot claimed she was busy doing work on her tablet and did not notice the drop in altitude as the plane carried around 280 passengers.

Scroll down for video

 Under investigation: A report by Boeing says the co-pilot fiddled with the aircraft's controls, says an official

India’s Directorate General of Civil Aviation launched an investigation and is reviewing a report prepared by The Boeing Company, which analysed the digital flight data recorder’s records.

A senior DGCA official told The Hindustan Times: ‘This appears to be a serious act of criminal negligence on part of the co-pilot.

‘It wasn’t as if the plane went into a free fall and the pilots were unaware of it.

'The Boeing report clearly establishes that the co-pilot fiddled with the controls of the aircraft after which the plane dropped 5,000 feet.’

In a statement provided to MailOnline Travel, the airline said: ‘Jet Airways has initiated an internal inquiry into the matter and shared the Boeing report with the regulator to assist with the investigation. However, the airline is unable to comment till such time the full investigations are over.

'Safety is of paramount importance to Jet Airways, as is also the welfare of our guests and crew and the airline will always take appropriate steps to ensure the same.’

The pilots received an emergency call from an air traffic controller in Ankara, who demanded to know why the aircraft had descended from its assigned flight level of 34,000ft.

Other aircraft were flying at the altitude that the commercial aircraft had descended to, and the airspace over Turkey is busier than normal as airlines avoid conflict zones in Iraq and Ukraine. 

The interior of a Boeing 777 cockpit is pictured in this file photo

The co-pilot awakened the pilot when the air traffic controller asked them to immediately ascend to 32,000ft.

But the crew did not report the incident to India’s Directorate General of Civil Aviation (DGCA) in their post-flight report.

The regulator was alerted when it received an anonymous text message about the uncontrolled descent involving the Mumbai-based airline.

DGCA officials have suspended the pilot and co-pilot pending the outcome of the investigation.

A source told the Times of India: ‘The commander was taking controlled rest, which means he was sleeping as per global airline norms where pilots take rest in the cockpit by turn on long flights.

‘The co-pilot, who was supposed to ensure that the aircraft flew steadily on its assigned path, told DGCA investigators that she was on her electronic flight bag, a tablet that has all aircraft documents loaded on to it.' 

India’s aviation regulator is looking into whether the captain's controlled rest was permitted at that time.