12 Apr 2013
Air India Flight AI-333 Airbus A321 from Bangkok(Thailand) to Mumbai with 166 passengers it was en route at cruising altitude when First officer asked a flight attendant to stay in his place for go to toilette as it is the standard procedure in this case.After little bit and the captain asked a flight attendant to stay in his place and monitor airplane even he did some little lesson and they both went to take a little nap in business class seats.Airplane stayed on autopilot but accidentally one flight attendant disengaged the autopilot and then both pilot came back to cockpit and engaged again autopilot and also took control of airplane.This information came to airlines management from a senior cabin crew member according to Mumbai Mirror.After that all 4 crew members involved with the incident had been suspended from company.
Air India released a statement and claiming that never the airplane stayed without pilot inside cockpit
Incident pending investigation
On 4 May 2013 India's Directorate General of Civil Aviation reported that 2 flight attendants it was inside cockpit almost all the flight and the autopilot disconnected while airplane it was at 33000 feet.The incident reported from a crew member
On 20 June 2013 India's Directorate General of Civil Aviation reported that data from voice recorders are not available because they erased from some mistake also that the captain and the 2 flight attendants they suspended from company for 3 months.Also they reported that the 2 flight attendant entered cockpit for bring some tea without pilots to order and after that they stayed there talking for various subject and taking attention from captain that accidentally diss engaged autopilot without to understand immediately , so it took sometime for he to understand and to engage again
Source
Mumbai Mirror