AI171 preliminary probe: 2018 report flagged fuel switch concern, but said it wasn't 'unsafe'
MUMBAI: The preliminary report of Aircraft Accident Investigation Bureau (AAIB) into the June 12 Air India flight 171 crash in Ahmedabad refers to a serviceability bulletin on the Boeing-787's fuel control switch which indicates a potential equipment malfunction, but deemed it was not an unsafe condition.
The AAIB report mentioned that the fuel switches of engine one and two of the Boeing 787-8 Dreamliner aircraft were cut off within a gap of one second and later turned on before the crash.
Capt Sam Thomas, president of the Airline Pilots' Association of India, said: "The AAIB report refers to a serviceability bulletin concerning the fuel control switch gates, which indicates a potential equipment malfunction. The tone and direction of the investigation suggest a bias toward pilot error.
ALPA categorically rejects this presumption and insists on a fair, fact-based inquiry."
What is the possible technical issue? The AAIB report refers to the 'Special Airworthiness Information Bulletin (SAIB) No. NM-18-33' issued by the US regulator, the Federal Aviation Administration (FAA), in Dec 2018. The bulletin is about the potential disengagement of the fuel control switch locking feature. The bulletin was issued after reports came in from operators of Boeing 737s that the fuel control switches were installed with the locking feature disengaged.
by Taboola
by Taboola
Sponsored Links
Sponsored Links
Promoted Links
Promoted Links
You May Like
'이것' 부족하면 운동 소용없다.. 갱년기 살찐 진짜 이유
워킹맘 로즈
더 알아보기
Undo
The said fuel control switch design, including the locking feature, is similar on various Boeing airplane models, including the B787, the aircraft that crashed.
The FAA recommended: "Inspect the locking feature of the fuel control switch to ensure its engagement. While the airplane is on the ground, check whether the fuel control switch can be moved between the two positions without lifting up the switch. If the switch can be moved without lifting it up, the locking feature has been disengaged and the switch should be replaced at the earliest opportunity."
The AAIB report said: "The airworthiness concern was not considered an unsafe condition that would warrant an airworthiness directive (AD) by FAA. As per information from Air India, the suggested inspections were not carried out as the SAIB was advisory and not mandatory."
Hashtags
Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles
Time of India
41 minutes ago
- Time of India
Air India replaced module in cockpit in crashed Dreamliner following Boeing directive
Air India replaced the Throttle Control Module (TCM) of the crashed Boeing 787-8 plane twice in the last six years following a directive from Boeing in 2019, sources said on Sunday. TCM includes fuel control switches, which have come to focus in the ongoing probe into the fatal crash as these switches were cut off immediately after takeoff of the ill-fated London-bound Dreamliner VT-ANB that crashed in Ahmedabad on June 12. The replacement of the TCM twice -- in 2019 and 2023 -- was mentioned in the Aircraft Accident Investigation Bureau's (AAIB) preliminary probe report into the crash that was released on Saturday. It also said the TCM replacement was not linked to the fuel control switches. by Taboola by Taboola Sponsored Links Sponsored Links Promoted Links Promoted Links You May Like When Knee Pain Hits, Start Eating These Foods, and Feel Your Pain Go Away (It's Genius) Read More Undo The source told PTI that a revised Maintenance Planning Document (MPD) was issued by Boeing for all the operators of the Dreamliners in 2019. As per the MPD, the operators have to change the TCM, which includes the fuel control switches, every 24,000 flight hours, the sources said. Live Events Since 2019, when the MPD was issued, the source said Air India changed the TCM in the ill-fated aircraft twice -- in 2019 and 2023. Queries sent to Air India remained unanswered. Specific details about the MPD could not be immediately ascertained. In response to questions sent to Boeing, a company spokesperson on Sunday referred to its statement issued on Saturday saying it will continue to support the investigation and Air India. "We will defer to the AAIB to provide information about AI171, in adherence with the UN International Civil Aviation Organization protocol known as Annex 13," the spokesperson said in the emailed statement. AAIB, in its report on Saturday, said that at this stage of investigation, "there are no recommended actions to B787-8 and/or GE GEnx-1B engine operators and manufacturers". Air India's Dreamliner VT-ANB, which crashed on June 12, was powered by GEnx-1B engines. According to the report, FAA issued Special Airworthiness Information Bulletin on December 17, 2018, regarding the potential disengagement of the fuel control switch locking feature. "This SAIB was issued based on reports from operators of Model 737 airplanes that the fuel control switches were installed with the locking feature disengaged. The airworthiness concern was not considered an unsafe condition that would warrant airworthiness directive by the FAA," it said. AAIB also said the fuel control switch design, including the locking feature, is similar on various Boeing airplane models including part number 4TL837-3D, which is fitted in B787-8 aircraft VT-ANB. "As per the information from Air India, the suggested inspections were not carried out as the SAIB was advisory and not mandatory. The scrutiny of maintenance records revealed that the throttle control module was replaced on VT-ANB in 2019 and 2023. "However, the reason for the replacement was not linked to the fuel control switch. There has been no defect reported pertaining to the fuel control switch since 2023 on VT-ANB," the report said. After being in cut-off mode, the fuel control switches of the aircraft's two engines were turned on later but the London-bound aircraft could not get enough thrust and altitude before it crashed into a building in Ahmedabad killing 260 people.
The Hindu
2 hours ago
- The Hindu
Interim report on Air India crash found no urgent safety concerns on Boeing 787-8 or its engines: FAA tells counterparts
The U.S. aviation safety regulator Federal Aviation Administration (FAA) has written to its counterparts around the world acknowledging the preliminary findings into the Air India Boeing 787-8 crash of June 12 and informing them that the report has 'found no urgent safety concerns' related either to the engines or airplane systems of the Boeing 787-8, according to a senior official of the Ministry of Civil Aviation. Also Read | AI-171 crew acted in line with responsibility under challenging conditions: AI pilots body The interim report of Aircraft Accident Investigation Bureau (AAIB), the Indian agency investigating the crash, stated that the switches that supplied fuel to the two engines on the aircraft shifted or 'transitioned' to the 'CUTOFF' position three seconds after the aircraft became airborne. Later, there was a loss of engine thrust and both engines shut down, resulting in the crash. In its July 11 notification, the FAA also acknowledged the reference in the preliminary report to the American regulator's advisory in December 2018 about the potential of the lock on the switch that supplies fuel to the engine getting disengaged. But the U.S. regulator made no new recommendations on safety measures needed by airlines. 'The FAA has said that it will continue to share relevant information,' the official quoted above said. Two-step action needed to move fuel switch The switches are guarded by brackets and feature a spring-loaded locking mechanism in order to prevent accidental activation. To move a switch from RUN to CUTOFF, a pilot has to perform a two-step action — lift the switch over a metal stop before pulling it down. While the U.S. regulator has not provided any new guidance, it has reminded the civil aviation authorities about its previous advisory, i.e, Special Airworthiness Information Bulletin (SAIB) dated December 17, 2018. There are 77 airlines across the world that have the Boeing 787 aircraft in their fleet. There are 171 Boeing 787 aircraft in the U.S., and 1,189 across the world. The AAIB report said that Air India did not carry out the recommendations made in the FAA's 2018 advisory on the potential disengagement of the lock on the fuel switches that required inspection of aircraft, as well as replacement of the switches carrying specific serial numbers with 'an improved locking feature'. It added that Air India explained that this was so because the FAA bulletin 'was an advisory and not mandatory'. The report also found that no defects in the fuel control switch of this aircraft had been reported after 2023, when the throttle control module of the cockpit control panel was last replaced on this aircraft. The FAA's Special Airworthiness Information Bulletin dated December 16, 2018, said the airworthiness concern is not an unsafe condition that would warrant airworthiness directive (AD) action. While an advisory provides a non-mandatory guidance, an AD provides mandatory guidance and recommendations to ensure airworthy aircraft.
Time of India
19 hours ago
- Time of India
AI171 preliminary probe: 2018 report flagged fuel switch concern, but said it wasn't 'unsafe'
Air India crash (Picture credit: ANI) MUMBAI: The preliminary report of Aircraft Accident Investigation Bureau (AAIB) into the June 12 Air India flight 171 crash in Ahmedabad refers to a serviceability bulletin on the Boeing-787's fuel control switch which indicates a potential equipment malfunction, but deemed it was not an unsafe condition. The AAIB report mentioned that the fuel switches of engine one and two of the Boeing 787-8 Dreamliner aircraft were cut off within a gap of one second and later turned on before the crash. Capt Sam Thomas, president of the Airline Pilots' Association of India, said: "The AAIB report refers to a serviceability bulletin concerning the fuel control switch gates, which indicates a potential equipment malfunction. The tone and direction of the investigation suggest a bias toward pilot error. ALPA categorically rejects this presumption and insists on a fair, fact-based inquiry." What is the possible technical issue? The AAIB report refers to the 'Special Airworthiness Information Bulletin (SAIB) No. NM-18-33' issued by the US regulator, the Federal Aviation Administration (FAA), in Dec 2018. The bulletin is about the potential disengagement of the fuel control switch locking feature. The bulletin was issued after reports came in from operators of Boeing 737s that the fuel control switches were installed with the locking feature disengaged. by Taboola by Taboola Sponsored Links Sponsored Links Promoted Links Promoted Links You May Like '이것' 부족하면 운동 소용없다.. 갱년기 살찐 진짜 이유 워킹맘 로즈 더 알아보기 Undo The said fuel control switch design, including the locking feature, is similar on various Boeing airplane models, including the B787, the aircraft that crashed. The FAA recommended: "Inspect the locking feature of the fuel control switch to ensure its engagement. While the airplane is on the ground, check whether the fuel control switch can be moved between the two positions without lifting up the switch. If the switch can be moved without lifting it up, the locking feature has been disengaged and the switch should be replaced at the earliest opportunity." The AAIB report said: "The airworthiness concern was not considered an unsafe condition that would warrant an airworthiness directive (AD) by FAA. As per information from Air India, the suggested inspections were not carried out as the SAIB was advisory and not mandatory."
