F-35 fighter jet development hampered by many bugs

Software bugs have left a jet fighter in development for 15 years unable "to provide accurate coordinates for precision attack" and with "limited ability to respond to threats".

The F-35's ejector seat had also "failed to meet neck-injury criteria", the US defence department has said.

Its development, by the Lockheed Martin company, has already cost $1 trillion (£0.7tn), partly funded by the UK.

And its UK planned deployment date has been put back from 2012 to 2023.

"It's one of the most delayed and problematic fighter programs in history," said Justin Bronk, a military analyst at the Royal United Services Institute (RUSI).

But he added: "They will make this thing work because they have no choice, there's no alternative.

"They will chuck whatever money they need to at it."