Follow TNM's WhatsApp channel for news updates and story links.
The preliminary probe into the Ahmedabad plane crash faulting an abrupt fuel cutoff for the tragedy has once again stirred debate. Even as those involved engage in blame shifting, it is important to examine a crucial mention made in the probe report of the Aircraft Accident Investigation Bureau (AAIB)—that of a December 2018 US Federal Aviation Administration (FAA) advisory that flagged a related issue on a few Boeing models.
TNM studied the FAA’s 2018 Special Airworthiness Information Bulletin (SAIB) that highlighted a potential malfunction of the fuel control switch in a few Boeing models, which includes 787-8, the one that crashed in Ahmedabad on June 12.
The FAA is a US government agency that oversees and regulates civil aviation within the country, as well as the National Airspace System.
The advisory said that some of Boeing’s 737 airplanes had fuel control switches with a disengaged locking feature. In the absence of the locking feature, the switch can be moved between the two positions without physically lifting it.
“The fuel control switch has a locking feature to prevent inadvertent operation that could result in unintended switch movement between the fuel supply and fuel cutoff positions … If the locking feature is disengaged, the switch can be moved between the two positions without lifting the switch during transition, and the switch would be exposed to the potential of inadvertent operation,” the SAIB explained.
It further warned, “Inadvertent operation of the switch could result in an unintended consequence, such as an in-flight engine shutdown.”
According to the advisory, Boeing informed the FAA that the switch design is similar on other models like the 787-8, the 787-9, and the 787-10. Even though it had ordered operators to inspect the affected airplanes, the concern is not an “unsafe condition”, the advisory had added.
The AAIB probe report of the Ahmedabad crash stated that the inspections were not carried out on Air India aircraft, as the SAIB was of an advisory nature, and not mandatory. Although the maintenance records of VT-ANB, the plane that crashed, reveal the throttle control module was replaced in 2019 and 2023, it was not an issue related to the fuel switches.
The probe also noted that no defect has been reported in the fuel switches of the crashed plane since 2023.
According to the AAIB report, the fuel control switches transitioned from “RUN” to “CUTOFF” exactly three seconds after the aircraft took off. Although the switches returned to “RUN” after a few seconds, the aircraft had started to lose altitude by then.
The report does not clarify whether the switch movement was deliberate or a mechanical error. According to the Cockpit Voice Recorder (CVR), the last words of one of the pilots was, “Why did you cut off?” to which the other responded that he didn’t do it.
The full transcript, including which pilot said what, has not been released yet. The AAIB also stated the probe is still in progress.
The Ahmedabad crash took the lives of 241 persons on the flight and several more on ground. The aircraft crashed into the BJ Medical College and the residential quarters of medical staff, which caused major structural and fire damages to five buildings. Vishwas Kumar Ramesh, a British citizen, is the sole survivor of the crash.