As of 1 May, the F-35 program has flown more than 100 flight hours with the 3i software and 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 calendar year 2016.

 Concluding Block 2B and 3i development and testing now allows the F-35 program to focus on completing Block 3F – the Full War fighting Capability software. 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. This will allow the entire enterprise to focus their  development and testing on the final Block 3F capability, moving us closer to ending the SDD program.