US F-35 Upgrade Stymied by Software Problems, Prompting Delivery Woes

Ever since its maiden flight almost 17 years ago, the US F-35 – an aircraft with a staggering per-plane cost of $70-$90 million – has been plagued by a long list of technical bugs affecting both hardware and software. The latest upgrade to the jet is again proving a challenge for defense giant Lockheed Martin.