Major Australian airlines have investigated a critical fire-fighting malfunction in some of their planes after revelations of a system failure onboard some Boeing aircraft.

Jetstar and Qantas have looked into the potentially deadly fault that exists in a “small number” of the Boeing 787 Dreamliners, which the airlines fly on domestic and international routes.

Boeing issued an alert to all airlines flying the popular plane, warning them the switch – which is used to put out engine fires – had failed in a small number of instances.

Long-term heating can cause the switch to stick in a locked position so it is unable to release the fire extinguishers, the aeroplane manufacturer said.

Long-term heating can cause the switch to stick in a locked position. Photo: Getty

Speaking to The New Daily, Boeing stressed that only a small number of planes had been found to have the malfunction.

“Less than one per cent of the engine fire switches in the 787 fleet has been found to present this issue, and when found, it is required that the part be replaced,” a Boeing spokesman said.

“The engine fire switch is used to discharge halon into the engine in the event of an engine fire. Engine fires are a very unlikely event.

“In such an event, (cutting) off of the fuel would likely solve the issue before use of the fire switch is needed.”

In February, the Federal Aviation Administration (FAA) in the United States issued mandatory instructions to air operators, announcing that the problem was “likely to exist or develop in other products of the same design”.

Stating that “the potential exists for an airline fire to be uncontrollable”, the US regulator ordered airlines to check the switch every 30 days.

In a statement to The New Daily, a spokesman for Qantas and Jetstar said its fleet “had been checked”.

“We’re aware of the directive made by the FAA in February and there’s been no impact to either the Qantas or Jetstar fleets,” the spokesman said.

Launched in 2011, the Dreamliner is the world’s most advanced long-haul aeroplane. They have larger windows, use less fuel and are notably quieter than other passenger planes.

Meanwhile, Boeing has been struggling to deliver its troubled 737 Max planes following the Ethiopian Airlines tragedy in March that killed 157 people, and an eerily similar crash involving the same model of plane that killed 189 people in Indonesia in October.

The planes were new Boeing 737 MAX 8 models and both crashed just minutes after take-off.

But the company’s declining deliveries took a positive turn this week when one of the world’s largest airline groups announced it would buy 200 of the jets.

The $35 billion deal represents a huge shift for International Airlines Group, which owns Aer Lingus, British Airways, Iberia and other European carriers and flies more than 113 million passengers a year.

IAG mostly uses rival Airbus’s A320 planes for its single-aisle fleet, although it does operate some Boeing wide-body jets.