DGCA has ordered that Air India reinspect the RAT systems on its entire fleet of Boeing 787 Dreamliners after a recent incident that saw the uncommanded deployment of the device on one such aircraft upon landing in Birmingham, UK. The US planemaker has also asked other 787 operators to report similar events that may have occurred worldwide.
As reported by the Times of India, the country’s aviation safety regulator, the Directorate General of Civil Aviation (DGCA), has asked Air India to reinspect the emergency power source system known as the RAT (Ram Air Turbine) for stowage integrity in all aircraft whose power conditioning module (PCM) was replaced in the recent past.
A Ram Air Turbine is an emergency backup system in aircraft that deploys to provide hydraulic and electrical power when primary power sources (the aircraft engines) fail. It works by using the aircraft’s forward motion to spin a small turbine, which drops from the underside of the fuselage, and provides power to critical flight control systems and avionics, allowing pilots to remain in control of vital aircraft systems in the event of an emergency.
The RAT is designed for emergencies like a dual-engine failure or total electrical system failure and was seen deployed when AI flight 171 suffered a dual-engine flameout and subsequently crashed upon takeoff in Ahmedabad, India, in June 2025.
However, the advisory was primarily driven by an incident that took place on October 4, 2025, when Air India flight AI117, operating from Amritsar (ATQ) to Birmingham (BHX), experienced automatic deployment of the RAT at approximately 500 feet during descent. The aircraft landed safely, and all onboard systems reportedly functioned normally throughout the flight, according to the airline.
According to a DGCA advisory, “Air India has been advised to review the work package of ‘D’ Check for the actions required in view of the change of PCM module, for any discrepancies.” The regulator explained that this system is rarely used in day-to-day operations and typically activates only when both engines fail or a major systems failure occurs—making its deployment a serious event.
However, Air India has clarified that despite the uncommanded activation of the RAT during the latter stages of flight AI117 on October 4, 2025, all onboard electrical and hydraulic parameters were reported to be normal on the aircraft at the time of the incident.
On October 6, 2025, following the AI117 incident in Birmingham, the Federation of Indian Pilots (FIP) requested the Directorate General of Civil Aviation (DGCA) to inspect the electrical systems on all Boeing 787 aircraft operating in India.
In a letter to the DGCA, FIP President GS Randhawa noted that the Aircraft Health Monitoring (AHM) system on the Boeing 787 had detected a fault in the Bus Power Control Unit (BPCU), which may have triggered the RAT deployment. “The Aircraft Health Monitoring system picked up a fault of the Bus Power Control Unit, which may have caused the auto deployment of RAT,” Randhawa said.
The BPCU is a critical component that manages an aircraft’s electrical power distribution, and any malfunction could disrupt power management and activate backup systems. The FIP said the incident highlights potential systemic electrical vulnerabilities in Boeing 787 aircraft. The federation referenced multiple past incidents and stressed the need for thorough checks of all B787 aircraft in the country.
Following that letter, India’s Civil Aviation Minister Ram Mohan Naidu said, “The DGCA is already on the job. And once we get to know more details, we are going to reach out to the necessary stakeholders to further see what the necessary things are that we need to do so that these things don’t happen.”
Besides Air India, DGCA has spread its investigation wider, and has asked aircraft manufacturer Boeing to provide a comprehensive report outlining the preventive measures to be implemented with respect to the uncommanded RAT deployment incident.
The regulator has also asked Boeing to provide detailed information regarding similar uncommanded RAT deployments that have occurred globally on Boeing 787 series aircraft in recent years, to discover whether there are patterns in the circumstances surrounding those deployments.
