A fire aboard a US Marine Corps F-35B was caused by a loose bracket designed to hold together electrical wires in the aircraft’s weapons bay, F-35 programme executive officer Lt Gen Chris Bogdan says.

The loose bracket allowed electrical wires to move and chafe, stripping the insulation around the wires. Those electrical wires sparked near hydraulic lines, igniting a fire in the right side weapons bay, Bogdan says.

The pilot landing safely without injuries according to the USMC. Meanwhile, the programme office had already identified the potential loose bracket issue and had started a process to retrofit the F-35B variant jets with a redesigned part.

The aircraft involved in the fire did not have the redesigned bracket but had passed an inspection. However, the bracket still dislodged, Bogdan says. Since then, the JPO has completed another inspection on the aircraft.

Bogdan also defended the USMC’s decision to continue flying the aircraft that day even though the service knew about the loose bracket.

“Flying military airplanes all have risk and this airplane is like no other,” he says. “Yes there are acknowledged risks.”

Source: FlightGlobal.com