Less than two weeks after a confidential report pointed to the possibility of pilot error in the fatal crash of an Air India Express flight from Dubai to Mangalore, another report indicated the possibility of a near-disastrous pilot error at the same airline just days later.
In what the Indian Directorate General of Civil Aviation called a "serious incident" in its investigation findings of November 23, an Air India Express flight on May 26 from Dubai to Pune, India, was pushed to the structural limits of the aircraft when the co-pilot caused a steep dive. The pilot, who was not in the cockpit, eventually regained control of the Boeing 737 from his second-in-command, who had fallen "into a panic situation", according to the report.
But by that time, it had already fallen more than a mile and accelerated to nearly the speed of sound, the report said.
Abhay Pathak, the regional head for Air India's operations in the Middle East declined to comment on the report. Air India Express is a low-cost subsidiary of Air India, India's national carrier.
The incident occurred about an hour after the flight's departure, somewhere over the Arabian Gulf. At an altitude of 37,000ft (11,300 metres), the plane was cruising on autopilot, but the co-pilot, identified as a 25-year-old with about 1,000 hours' flying experience, accidentally bumped the control yoke, disengaging the autopilot.
The plane began to dive, although the autopilot remained in control of the aircraft's throttles.
The pilot was not in the cockpit, having left to use the restroom. But when he attempted to re-enter, he could not because, according to the report, the co-pilot was so panicked that he could not trigger the door latch.
When he did finally enter the cockpit, more than 20 seconds after the dive began, the co-pilot was still pushing the nose down even as the pilot struggled to pull it back up, according to the report.
Less than a minute after the dive began, the plane was levelled off and eventually returned to its cruising altitude. The crew told passengers the aircraft had hit an "air pocket," according to the report.
The report said the incident was triggered as the co-pilot readjusted his seat and persisted because he panicked.
"The co-pilot had not put on the seat harness and probably had no clue to tackle this kind of emergency," the report said.
Although there were no injuries and the twin-engine aircraft was not damaged and landed safely, the report said "appropriate action" would be taken against the flight crew, although it did not specify what.
After criticism over delayed investigations and reports about the Mangalore crash, in which 158 people died after the plane plunged into a valley while trying to land, the Indian civil aviation authority launched an inquiry.
No final findings have been released.
Binit Somaia, the South Asia director for the Centre for Asia Pacific Aviation, consultants to aviation businesses around the world, said although he could not comment directly on the latest incident, the rapid growth of air traffic and demand for flights between the Gulf and India has become a critical issue for airlines.
"The demand for skilled manpower will become more intense," Mr Somaia said. "Airlines will need to establish effective human resource plans to ensure that growth is managed safely and efficiently.
"And it will not be acceptable to maintain current accident rates: on that basis, if traffic doubles, the number of accidents will double. The goal must be to improve the rate of safety incidents and will primarily be achieved through better training."