Uncommanded RAT Deployment on Air India AI117: DGCA Probes

(BIRMINGHAM, UNITED KINGDOM) Air India AI117 landed safely at Birmingham Airport on October 4, 2025 after the aircraft’s RAT emergency system unexpectedly deployed during final approach, according to information released by India’s aviation authorities and pilot groups. The uncommanded deployment of the Ram Air Turbine—an emergency device that pops out into the airflow to create backup hydraulic and electrical power—occurred at roughly 400–500 feet above ground level as the Boeing 787-8 Dreamliner descended to land.

While no injuries were reported and the crew completed the approach without further incident, the unscheduled activation has triggered a formal safety probe and renewed concern across India’s Boeing 787 fleet.

What happened on flight AI117

• The aircraft, registration VT-ANO, was operating a routine service from Amritsar to Birmingham when the RAT deployed, despite initial checks showing the jet’s main systems functioning as expected.
• The crew continued the approach and touched down normally. After parking, maintenance teams and flight crew assessed systems and confirmed both electrical and hydraulic functions remained available despite the RAT being deployed.
• That outcome—an emergency deployment with no confirmed loss of main power—has raised pointed questions among engineers and regulators about what precisely triggered the backup mechanism.

After the safe landing:
– Air India grounded the aircraft on arrival for a detailed inspection.
– The airline cancelled the planned return leg, AI114 to Delhi, and rebooked passengers on alternative services.
– Disruptions rippled through schedules for several hours while passengers were matched to other flights and crew/maintenance rosters were adjusted.

Air India said it followed immediate safety and maintenance protocols and completed Boeing’s recommended checks. After those checks found no discrepancies, the Dreamliner was cleared for further operations, though the broader DGCA investigation remains active.

Regulatory response and investigation scope

India’s Directorate General of Civil Aviation (DGCA) opened a probe and assigned an officer from the Directorate of Air Safety to determine the root cause of the uncommanded deployment.

Investigators will examine:
– Maintenance records and recent component replacements
– Sensor data and the aircraft’s fault logs
– Cockpit voice recorder (CVR) and flight data recorder (FDR) to reconstruct the final minutes of flight, including electrical bus status and any fault flags
– Possible teardown inspections of the Bus Power Control Unit (BPCU) and associated wiring harnesses to look for intermittent faults

The RAT—often called the “flying windmill”—normally deploys only if the jet loses key power sources. In this case, it appears to have deployed without a confirmed failure of primary power channels.

Because Boeing’s initial checklist inspections found no issues, investigators expect the inquiry to lean heavily on recorded parameters and bench testing to simulate flight conditions and stress hardware under controlled conditions.

Technical focus: BPCU and Aircraft Health Monitoring

A letter from the Federation of Indian Pilots (FIP) noted the aircraft’s Aircraft Health Monitoring system flagged a potential fault in the BPCU. The BPCU helps manage how power is routed through the aircraft’s electrical buses.

• If the system senses a power problem—or believes one has occurred—it can trigger protective responses, including RAT deployment on some models.
• The FIP urged a comprehensive electrical system inspection across India’s Boeing 787 fleet to rule out a systemic fault.
• Pilots stressed that the RAT should never deploy “by surprise” when main power appears stable, because any false trigger can distract the crew at a critical phase of flight.

Context: recent industry events

• In June 2025, Air India Flight AI171 (Ahmedabad) crashed after both engines lost power following a fuel supply cutoff; the RAT deployed during that emergency. The crash killed 260 people and remains under investigation.
• While no direct link has been established between AI171 and AI117, the recent history has sharpened scrutiny of any RAT-related irregularities on the Dreamliner. Pilot associations and safety experts have pushed for more detailed checks even when basic tests show no obvious fault.

Operational and passenger impact

For passengers and communities that rely on India–UK routes, the safe landing brought relief but also fresh questions about handling rare technical events near the ground. The final approach phase offers little margin for error: the aircraft is low, slow, and crews face high workloads preparing for touchdown.

On AI117:
– Passengers remained unharmed, and the crew managed communications and the landing without panic or reported disruption on board.
– The operational impact came later with the aircraft’s grounding and the cancellation of AI114, which forced rebooking and longer travel times for some.

Practical advice for travelers affected by technical disruptions:
1. Keep all boarding passes, gate change notices, and rebooking confirmations in one folder.
2. If your UK visa or arrival obligations are time-bound, contact your school or sponsor immediately to document delays.
3. Confirm onward plans at the airport before leaving—airline staff can often reroute you via other hubs.
4. Notify anyone expecting you at the airport so they can adjust pickups or schedules.
5. Review your travel insurance for coverage of delays and missed connections caused by technical issues.

Birmingham Airport adapted staffing and coordination with airlines as rebooked passengers arrived on later flights. If you hold time-sensitive documents or depend on pre-booked services, plan for extra time after a re-route.

Why this matters technically

The RAT exists as a last line of defense. On twin-aisle jets like the 787 it can generate hydraulic pressure and limited electrical power to keep critical systems alive long enough to land safely. Crews are trained to:
– Fly the aircraft first
– Run the checklists
– Confirm data before taking further action

When a RAT emerges without a clear cause, it signals either a genuine power problem or that the aircraft’s logic thought one occurred. The BPCU sits at the center of that logic: it helps decide power routing, load shedding, and which buses feed key systems. An intermittent sensor issue or wiring problem that mimics a real fault could lead to a surprise deployment.

Potential regulatory and manufacturer actions

Possible outcomes from the DGCA probe include:
– Targeted inspections or part replacements across the fleet if a specific component fault is found
– Service bulletins or software patches from Boeing if logic or software issues are identified
– Enhanced monitoring requirements even if no single fault is found, with crews and maintenance logging extra details after flights

Air India and Boeing have emphasized that recommended checks were followed and that the aircraft was returned to service only after passing those checks. The DGCA’s probe remains open as of October 6, 2025.

Key takeaways for stakeholders

Three themes emerge from the AI117 incident:
– Training and crew discipline mattered. The crew completed the approach and landing safely despite the unexpected RAT deployment.
– Data is central to modern investigations. High-fidelity recordings from the 787’s systems will guide root-cause findings more than a single visual inspection.
– Transparency builds public trust. The DGCA’s probe and the FIP’s call for fleet checks show a system willing to ask tough questions even when initial inspections find nothing.

Air India prioritized a thorough inspection over a rushed turnaround by grounding the airframe and cancelling the return leg. For affected passengers, prompt re-accommodation and clear communication reduced longer disruptions.

Wider implications for the India–UK corridor

• Modern aviation relies on redundancy; the RAT alone is a backup and not a sign of failure by itself.
• The recent clustering of RAT-related events in 2025 has motivated calls for extra vigilance and potential systemic checks across Dreamliner fleets operating in India.
• For travelers, simple precautions—checking flight status, keeping contact details up to date, and holding important documents close—help smooth last-minute changes.

For airlines and regulators, the incident underscores a balance between automated protections and crew authority. Engineers will explore technical mitigations—improved sensor checks, tighter logic thresholds, or updated maintenance practices—to reduce false triggers. These are technical changes with human impacts: fewer surprises for pilots and smoother journeys for passengers.

On-the-ground response at Birmingham

After gate arrival, ramp crews and maintenance teams:
– Assessed the RAT housing and checked hydraulic and electrical buses
– Coordinated with Air India’s operations center about whether to replace components immediately or position a spare aircraft
– Opted to cancel the return flight and rebook passengers, prioritizing thorough checks over a rushed turnaround

Each choice weighed maintenance capacity, crew duty limits, and downstream schedules.

Final status and where to find official guidance

• Official message: the aircraft landed safely, all passengers and crew were unharmed, the airframe was grounded for checks, the return leg was canceled, and the DGCA is investigating.
• Pilot groups continue to press for thorough electrical system checks to restore confidence across operators.

For official background on India’s civil aviation safety oversight, refer to the Government of India’s Ministry of Civil Aviation at Ministry of Civil Aviation, Government of India. While the DGCA’s investigation continues, Air India and Boeing say they will support the process fully, and pilot groups will press for thorough electrical system checks.

The focus now turns to the data from AI117’s approach into Birmingham Airport and what it reveals about the precise trigger for the RAT emergency system. Until the investigation concludes, the path forward is clear: careful analysis, transparent findings, and practical steps to keep crews confident and passengers safe on every flight.