After safety scares, turbine rechecks ordered on AI Boeing Dreamliners

In the wake of two recent mid-air technical incidents involving Air India’s Boeing 787 Dreamliners, the Directorate General of Civil Aviation (DGCA) has directed the airline to re-inspect the emergency power source, known as the Ram Air Turbine (RAT), on all aircraft where the power conditioning module (PCM) was recently replaced.

The aviation regulator has also sought a detailed report from aircraft manufacturer Boeing, seeking clarity on global preventive measures after the un-commanded RAT deployment incident on one of Air India’s 787s. The move follows a stinging letter from the Federation of Indian Pilots (FIP) to the Union Civil Aviation Minister demanding the grounding of all Boeing 787s operated by Air India. The pilots’ body alleged “repetitive and worsening electrical malfunctions” on Dreamliners and called for a special DGCA audit of the airline’s maintenance operations.

According to the FIP, the most recent scare occurred on October 9 when flight AI-154 from Vienna to Delhi, a Boeing 787 registered VT-ANO, was forced to divert to Dubai after its autopilot system abruptly failed mid-flight. The failure, the letter said, led to “a cascade of malfunctions” affecting the instrument landing system (ILS), flight directors (FDs) and flight control system, leaving pilots to manually fly the aircraft before diverting to safety.

Just days earlier, on October 4, another Air India Boeing 787 operating the Amritsar-Birmingham flight (AI-117) experienced a sudden deployment of the RAT at around 400 ft during landing. While the pilots managed to land safely, the event raised fresh alarm within the aviation safety circles.

A senior DGCA official confirmed that Air India has been instructed to re-inspect the RAT stowage on all aircraft with recently replaced PCM modules. “Further investigation is ongoing and Boeing has been asked to submit a comprehensive report on the preventive measures being implemented,” the official said.

The RAT, a small turbine that automatically deploys during dual engine or total electrical failures, uses wind speed to generate emergency power for critical systems. The PCM, meanwhile, is a key component that regulates and distributes electric power from the aircraft’s generators to onboard systems.

Following the October 4 incident, Boeing-recommended maintenance checks for un-commanded RAT deployment were completed and no discrepancies were observed. The aircraft was subsequently cleared and ferried back to Delhi on October 5, according to DGCA officials.

Despite the regulator’s intervention, Air India has denied any electrical failure in its Boeing 787 fleet. The airline said the Vienna–Delhi diversion was caused by a “technical issue”, adding that passenger safety was never compromised.

DGCA has also advised Air India to review the ‘D Check’ maintenance package, one of the most extensive overhauls in aircraft maintenance, to identify any procedural lapses linked to the PCM change.

In its communication to Boeing, the regulator has asked for data on similar RAT deployment incidents reported globally across the 787 fleet, along with any service difficulty reports filed after PCM replacements.