The F-35 Joint Program Office (JPO) has completed development of the aircraft’s software blocks 2B and 3i, according to a statement from prime contractor Lockheed Martin [LMT].
Lockheed Martin spokesman Mark Johnson said Monday Block 3i software will provide the F-35 with initial warfighting capability on upgraded computer hardware. Johnson said Block 3i is the software that the Air Force will use to declare initial operational capability (IOC) in August.
With development of these two blocks complete, Johnson said the program will now focus on completing software Block 3F, which contains the full initial warfighting capability for all variants. Johnson said the improvements to blocks 2B and 3i have been transferred to Block 3F and all developmental test aircraft and labs have also been upgraded to Block 3F. This, he said, will allow the F-35 program to focus development and testing on the final Block 3F capability, moving it closer to ending the system design and development (SDD) portion in 2017.
Johnson said as of May 1, the F-35 program has flown more than 100 flight hours with the Block 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, Johnson said, will begin upgrading the F-35 fleet (low-rate initial production aircraft lots 6, 7 and 8 aircraft) with 3i software starting Monday.
F-35 Program Executive Officer (PEO) Air Force Lt. Gen. Christopher Bogdan told lawmakers in March that Block 3i software instability is caused when miscommunications between the aircraft’s computers and sensors build up, eventually triggering the sensor to restart mid-flight. He said in April that the F-35 program reduced software instability incidents from once every three to four hours to about once every 15 hours (Defense Daily, April 26).
Johnson said 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 Block 2B software, he said, will be used to start upgrading low rate initial production (LRIP) lots 2-5 aircraft by the end of May. Johnson said the entire fleet of fielded F-35 aircraft will eventually be upgraded to these two new software versions by the end of 2016.