ECONOMYNEXT – US Federal Aviation Authority knew of a problem with fuel control switches of older Boeing aircraft but a full airworthiness directive (AD) had not been issued at the time, reports said as investigators found that fuel had been shut-off without the knowledge of the pilots, in an Air India 787 that crashed.
An AD leads to the mandatory rectification of an identified problem, which can be solved either with a component change or modified operating instructions to operators and pilots.
Airlines however were issued a ‘Special Airworthiness Information Bulletin’ by the FAA to check on the problem of the locking switch, made by Honeywell, a US aerospace company, and also report back if they found anything.
“Inspect the locking feature of the fuel control switch to ensure its engagement,” bulletin said. “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 preliminary report by Indian investigators say no inspections were carried out as the advisory was not a full AD. But ‘throttle control modules’ were replaced twice on issues unrelated to the locking switch.
The investigation report did not say whether replacement of control modules included the locking switch or not.
ne pilot was asking the other why fuel was cut off to the engines, the investigation report said.
The other denied that he had cut off the fuel.
The pilots had managed to start one engine but had failed to start the other. The aircraft had crashed moments later.
Boeing had received reports from B-737 operators (a smaller widely used aircraft than the 787) that the fuel “with the locking feature disengaged,” the FAA information bulletin said.
“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,” the bulletin said.
“In order to move the switch from one position to the other under the condition where the locking feature is engaged, it is necessary for the pilot to lift the switch up while transitioning the switch position.
“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. Inadvertent operation of the switch could result in an unintended consequence, such as an in-flight engine shutdown.
“Boeing informed the FAA that the fuel control switch design, including the locking feature, is similar on various Boeing airplane models.”
The information bulletin listed the B-787 as a model that could have the problem.
It is not clear whether the problem existed in the Air India Boeing at all or whether it was checked or rectified. Later aircraft had a newer part according to the information bulletin.
In air crashes there is sometimes political pressure to blame ‘pilot error’ observers say, when the actual fault is more complex and there is a chain of miss-steps for which multiple parties are responsible, including the manufacturer, regulators and also airlines if ADs are ignored.
The pilots are usually dead and cannot defend themselves.
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(Colombo/July12/2025)
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