U.S. defense chiefs have made little progress in fixing technical problems with their new F-35 all-weather stealth combat jets, according to a report by a Washington-based anti-corruption body.

The Project On Government Oversight (POGO) said Wednesday that it had obtained a document revealing how Lockheed Martin’s long-troubled F-35 project was still encountering design flaws and other technical issues.

“The Joint Strike Fighter Program Office’s Deficiency Report Metrics document, dated February 28, 2020, shows the program is currently dealing with 883 unresolved design flaws — and has no plan for correcting over 160 of them,” said an article on POGO’s

Read more: Engineers in US still grappling with F-35 flaws: report