Mid-air RAT deployment: DGCA finds no discrepancy, assigns official for probe

Days after an Air India (AI) Boeing 787 Dreamliner suffered an ‘uncommanded’ deployment of its Ram Air Turbine (RAT) during a flight from Amritsar to Birmingham, the Directorate General of Civil Aviation (DGCA) on Monday said all Boeing-recommended maintenance checks had been carried out and “no discrepancy had been observed”.

A senior DGCA official said the aircraft had been cleared for service. The regulator said the matter “required detailed investigation”, and an officer from the DGCA’s Directorate of Air Safety (Northern Region) had been assigned for probe.

The official further said that Boeing had also issued a ‘Fleet Team Digest’ summarising earlier instances of such occurrences.

According to the regulator, on October 4, Air India’s B787-8 aircraft (VT-ANO) operating flight AI-117 to Birmingham saw a RAT unlock message and automatic deployment at around 400 feet during landing. Despite the alert, the pilots reported no associated abnormalities and the aircraft landed safely.

Meanwhile, in an email sent to the DGCA with a copy to the AAIB DG and MOCA Secy on Sunday, the Federation of Indian Pilots’ (FIP) noted that the malfunction occurred when the RAT deployed automatically at around 500 ft while approaching Birmingham.

“In this incident, the Aircraft Health Monitoring has picked up a fault of the Bus Power Control Unit, which may have caused the auto deployment of RAT,” the email read.

It further said that the DGCA’s earlier post-crash inspections were superficial and failed to look at the larger electrical issues. The pilots’ body, which represents over 5,500 pilots across airlines, said the incident “must serve as a wake-up call” for the regulator.

This is the second major incident involving the same aircraft model and deployment of RAT since June 12 when Air India’s Boeing 787 flight AI171 from Ahmedabad crashed shortly after take-off, killing 260 people on board. The Aircraft Accident Investigation Bureau (AAIB) is probing that crash, with initial findings suggesting both engines shut down seconds after lift-off.