The Directorate General of Civil Aviation (DGCA) has instructed Air India to conduct a reassessment of the Ram Air Turbine (RAT) emergency system on its Boeing 787 aircraft following an unexpected activation during Flight AI 117 from Amritsar to Birmingham on October 4.
India’s Aircraft Accident Investigation Bureau (AAIB), under the Union Aviation Ministry, has clarified that the unanticipated deployment of the emergency turbine on Air India’s Amritsar-Birmingham Boeing 787 aircraft on October 4 is unrelated to the June 12 mishap involving the same airline which experienced a similar incident post-takeoff, as reported by Reuters from sources close to the ongoing investigation.
DGCA sources revealed that Air India has been instructed to review the maintenance procedures conducted during the recent ‘D’ check on the aircraft, specifically focusing on activities related to the replacement of the Power Conditioning Module (PCM), and to identify any discrepancies.
Additionally, the airline has been directed to reexamine the RAT storage on all planes where the PCM module was previously replaced.
The investigation by DGCA into the Amritsar to Birmingham aircraft incident is ongoing, with the regulatory body requesting a detailed report from Boeing. The aircraft manufacturer has been asked to furnish a comprehensive overview of similar uncommanded RAT deployments on Boeing 787 aircraft globally and suggest preventive measures to avert future incidents.
DGCA has also sought detailed information on any service difficulty reports received worldwide from operators post PCM module replacements.
This action follows the recent occurrence of an uncommanded deployment of the Ram Air Turbine (RAT) mid-flight on an Air India Boeing Dreamliner 787-8 aircraft operating from Amritsar to Birmingham, Flight AI 117, which landed safely.
After the event, Air India confirmed that all electrical and hydraulic systems were functioning normally upon landing, and the aircraft was grounded for a thorough inspection as per protocol.
The DGCA reported that the RAT deployed as the aircraft approached Birmingham, approximately 400 feet above ground level, with the pilot detecting no issues and executing a safe landing.
It is noteworthy that the Boeing 787-8 Dreamliner involved in this recent incident was previously involved in the Ahmedabad crash in June, where the RAT also deployed. A preliminary investigation revealed that engine shutdowns, due to a fuel supply cutoff, triggered the emergency system.