Pilots express concerns about the engine fire-extinguishing system of the Boeing 787 Dreamliner

Boeing talks about a minor problem but several pilots have expressed their fear

Several Boeing 787 Dreamliner aircraft have encountered a technical problem with the engine fire-extinguishing system, the manufacturer told English newspaper The Guardian.

The system has failed in a limited number of cases, says Boeing in a warning to airlines. High temperatures for a long time may cause the switch activating the extinguishing system to stick in the locked position. This switch should normally ensure that the fuel supply and the hydraulic fluid are stopped, to avoid further feeding the flames.

Boeing talks about a minor problem, saying that fewer than one percent of the fire switches have proved defective, but several pilots have expressed their concerns. “If there was an engine fire on a transatlantic flight and the aircraft had one of the defective fire switches, then we would have to fly with a burning wing for up to three hours before we could safely land,” a pilot with a British airline told the Observer.

The FAA has issued an airworthiness directive announcing that the problem is “likely to exist or develop in other products of the same design” and that “the potential exists for an airline fire to be uncontrollable”. However, the FAA ruled that the aircraft should not be grounded, but airlines will have to test the system at least once every month.

This is not the first problem affecting the Dreamliner. The Boeing 787 aircraft were grounded in 2013 following a series of fires caused by leaking batteries. In 2017 the FAA ordered the company to improve its quality control after metal shavings were found among electrical wiring, causing a fire hazard.