The F-35 Joint Program Office (JPO) has completed development of F-35 software block 3i, the same software the US Air Force will use to declare Initial Operational Capability (IOC) later this year. The Block 3i software provides F-35s with initial combat capability on upgraded computer hardware.
Until last week, the F-35 program had flown more than 100 flight hours with the 3i software and according to a JPO statemrnt, it has shown approximately twice the level of stability as the previously fielded Block 2B software and three times better stability than the original 3i software.
The JPO will begin to upgrade the F-35 fleet (LRIP 6, 7, and 8 aircraft) with 3i software the week of 9 May. The same stability and mission effectiveness enhancements have also been incorporated into a new version of Block 2B software, for the benefit of earlier fleet aircraft.
The new version of 2B software will be used to start upgrading LRIP 2-5 aircraft by the end of May. The entire fleet of fielded F-35 aircraft will eventually be upgraded to these two new software versions by the end of 2016.
Concluding Block 2B and 3i development and testing now allows the F-35 program to focus on completing Block 3F – the software block that should provide full combat capability. The improvements to Block 2B and 3i have been transferred to Block 3F, and all developmental test aircraft and labs have been upgraded to Block 3F.