The international air show debut of the Lockheed Martin F-35 Joint Strike Fighter is in doubt after the US Department of Defense grounded the entire fleet on 3 July.

Based on the findings of an initial report into the 23 June fire that broke out aboard an F-35A at Eglin AFB, the DoD has mandated further checks of the JSF fleet’s Pratt & Whitney F135 powerplants.

It says: “Additional inspections of F-35 engines have been ordered, and return to flight will be determined based on inspection results and analysis of engineering data.”

As well as being yet another setback for the programme, the move puts the stealthy type’s appearance at the Royal International Air Tattoo (RIAT) and the Farnborough air show into serious doubt.

Lockheed Martin was due to deploy three short take-off and vertical landing F-35Bs to the UK to ensure a presence at the events.

The DoD says that “preparations continue” for the type’s participation at RIAT and Farnborough, with a decision to be taken “early next week”.

A Lockheed Martin source adds: “We are well within the arrival window to support RIAT and Farnborough.”