"Several essential capabilities – including aimed gunshots and Air-to-Air Range Infrastructure – had not yet been flight tested or did not yet work properly when Block 3FR6 was released," according to DOT&E's review. "The services [Air Force, Marine Corps, and Navy] ... designated
276 deficiencies in combat performance as '
critical to correct' in Block 3F, but
less than half of the critical deficiencies were addressed with attempted corrections in 3FR6."
On top of that, DOT&E said that the delays with Revision 6, coupled with funding problems, had forced the F-35 program office to
scrap its own existing plans for two follow-on software blocks, 3FR7 and 3FR8. At this point, it seems almost impossible to assess the true capabilities of any “Block 3F” code, positively or negatively, based on public descriptions, especially given the sheer number of major revisions and minor changes.
But most significantly, thanks to the Freedom of Information Act, we do know that the service already deliberately watered down its capability criteria to meet its own, self-imposed schedule for declaring IOC with the F-35A in August 2016. This was mainly
out of fear that delaying the milestone any further would become a political and public relations nightmare that could've potentially impacted Congressional support and foreign sales.