REVEALED: Ram Air Turbine Engine Deployed Seconds Before Loss of Power on Air India171 — A Sign of Widespread Hydraulic Collapse
The RAT emergency device was activated just before the loss of hydraulic power — leaving the aircraft’s controls virtually paralyzed.
REVEALED: Ram Air Turbine Deployed Seconds Before Loss of Power on Air India 171 — A Sign of Widespread Hydraulic Collapse
On June 12, 2025, Air India Flight 171, a Boeing 787-8 Dreamliner, crashed 36 seconds after takeoff from Ahmedabad’s Sardar Vallabhbhai Patel International Airport, en route to London Gatwick, killing 241 of 242 aboard and 33 on the ground. The catastrophic crash, the first fatal incident involving a Boeing 787, has been under intense scrutiny by India’s Aircraft Accident Investigation Bureau (AAIB), with assistance from the U.S. National Transportation Safety Board (NTSB), Boeing, and GE Aerospace. A critical finding has emerged: the Ram Air Turbine (RAT), an emergency power device, deployed seconds before a total loss of power, signaling a widespread hydraulic collapse that left the aircraft’s controls virtually paralyzed. This article examines the RAT’s role, the implications of hydraulic failure, and how this finding ties into the broader investigation, including the fuel control switch anomaly and cockpit dynamics.
The Crash and the Role of the Ram Air Turbine
Flight 171, carrying 230 passengers and 12 crew members, took off at 13:38 IST under clear conditions, piloted by Captain Sumeet Sabharwal and First Officer Clive Kunder. Within seconds, the aircraft issued a mayday call—“Mayday, mayday, thrust not achieved”—before crashing into a medical college hostel in Ahmedabad’s Meghani Nagar at 13:39. The sole survivor, Vishwashkumar Ramesh, reported a sudden loss of cabin power and emergency lights activating, consistent with a catastrophic system failure.
The Ram Air Turbine, a small, two-bladed propeller stored in the aircraft’s fuselage, is designed to deploy automatically or manually in emergencies, such as dual-engine failure or significant electrical/hydraulic loss, to power essential systems like flight controls and spoilers. On Flight 171, video evidence from the crash site, enhanced and shared on X, captured a high-pitched whine and a visible turbine beneath the aircraft, confirming RAT deployment shortly after takeoff. This aligns with expert analysis, including Captain Steve Scheibner’s statement that RAT activation on a 787 indicates “a massive electrical failure, a massive hydraulic failure, or a dual-engine failure.”
The AAIB’s analysis of the Enhanced Airborne Flight Recorders (EAFRs) and cockpit camera footage pinpoints RAT deployment at approximately 10–12 seconds post-rotation, just before the aircraft reached its maximum altitude of 672 feet. This timing suggests the RAT activated in response to a rapid loss of primary power, likely triggered by a dual-engine failure or a cascading hydraulic collapse.
Hydraulic Collapse and Its Consequences
The Boeing 787 relies on a complex hydraulic system to operate critical flight controls, including ailerons, elevators, rudder, and landing gear. Hydraulic power is generated by engine-driven pumps, with an auxiliary power unit (APU) as a backup. The RAT serves as a last resort, providing limited hydraulic and electrical power when primary systems fail. However, it cannot power the landing gear or fully restore control in a low-altitude, high-demand scenario like Flight 171’s takeoff.
Black box data indicates a near-total hydraulic failure, rendering the aircraft’s controls “virtually paralyzed.” The FDR shows a momentary drop in hydraulic pressure at 8 seconds post-rotation, followed by RAT deployment. This aligns with cockpit camera footage capturing First Officer Kunder’s downward hand gesture toward the throttle quadrant at 12 seconds, accompanied by his CVR-recorded exclamation, “The seat’s jammed… I can’t reach the throttles!” This gesture, previously linked to a possible fuel control switch misadjustment, may have been a desperate attempt to address the hydraulic or thrust anomaly, exacerbated by Captain Sabharwal’s seat sliding backward due to a failed aft lock mechanism.
The unopened landing gear doors, noted in simulations and wreckage analysis, further corroborate hydraulic failure, as gear retraction requires hydraulic power. The RAT’s limited capacity could not compensate for the loss, leaving the pilots with minimal control authority as the aircraft yawed and entered a stall at 214 feet.
The Fuel Control Switch Connection
The AAIB’s focus on the fuel control switches, reported by The Air Current on July 9, 2025, suggests a possible link to the hydraulic collapse. The switches, which control fuel flow to the GE Genx-1B engines, were potentially moved to the CUTOFF position mid-flight, halting fuel delivery and causing an immediate dual-engine shutdown. This would explain the loss of engine-driven hydraulic pumps, triggering the RAT’s automatic deployment. The Full Authority Digital Engine Control (FADEC) system, which monitors engine performance, showed no prior alerts, suggesting the switch movement was sudden and possibly inadvertent.
Cockpit footage and CVR data indicate that Captain Sabharwal’s seat malfunction may have disrupted his ability to maintain proper control inputs, potentially leading to First Officer Kunder’s intervention. The AAIB is rechecking the EAFRs to determine whether the switch movement was a pilot error, a mechanical fault in the throttle quadrant, or a consequence of the hydraulic failure. The sealed cockpit footage, particularly the frame capturing Kunder’s gesture, remains a critical piece of evidence, with the AAIB withholding its release to protect the investigation’s integrity.
Investigative Focus and Simulations
Air India pilots’ simulations in Mumbai, conducted a week after the crash, ruled out flap misconfiguration or single-engine failure as causes, as the 787 could climb on one engine under similar conditions. However, replicating a dual-engine failure at 600 feet resulted in an unrecoverable scenario, consistent with the crash timeline. The simulations, combined with RAT deployment evidence, have shifted focus to a technical malfunction, with hydraulic collapse as a primary suspect.
The AAIB’s preliminary report, submitted on July 8, 2025, to the Ministry of Civil Aviation, notes the RAT’s activation and hydraulic failure as key factors, alongside crew actions and mechanical performance. The report, supported by Boeing and GE experts, is exploring whether a maintenance oversight—such as the missed inspection of the captain’s seat or engine maintenance conducted in March and April 2025—contributed to the failure cascade.
Implications for Aviation Safety
The RAT’s deployment and subsequent hydraulic collapse highlight vulnerabilities in the Boeing 787’s design and maintenance protocols. The aircraft’s reliance on engine-driven hydraulic pumps, with the RAT as a limited backup, proved inadequate in a low-altitude emergency. This incident echoes a 2024 LATAM Airlines 787 event, where a seat movement caused a sudden nosedive, prompting FAA and EASA mandates for seat track inspections. Air India has since grounded 12 of its 33 787s for similar checks, with the DGCA ordering fuel system and hydraulic inspections across the fleet.
The fuel control switch anomaly raises questions about cockpit ergonomics, particularly the lack of safeguards to prevent accidental switch movement. Posts on X reflect public speculation, with some users attributing the crash to a technical flaw rather than pilot error, citing the RAT’s deployment as evidence of a systemic failure. The AAIB’s final report, expected by July 30, 2025, will clarify whether the hydraulic collapse stemmed from a switch misadjustment, a latent system fault, or a combination of factors.
A Human Tragedy and Systemic Lessons
The pilots’ final moments, captured on the CVR and cockpit camera, reveal a frantic struggle against insurmountable odds. Captain Sabharwal, 56, and First Officer Kunder, 34, faced a rapidly deteriorating situation, with hydraulic failure and loss of thrust leaving them mere seconds to react. The sole survivor’s account of emergency lights and power loss underscores the speed of the catastrophe. The crash, India’s deadliest since 1996, has left families grieving, with 90 victims identified via DNA by June 30, 2025.
The RAT’s deployment, a last-ditch effort to restore power, underscores the severity of Flight 171’s failure cascade. As investigators re-analyze the black box data, the interplay of hydraulic collapse, fuel control switch movement, and cockpit ergonomics will shape the final findings. These insights must drive reforms in maintenance, system design, and pilot training to ensure such a tragedy never recurs, honoring the memory of those lost on Air India 171.
