The US Air Force plans to declare initial operational capability (IOC) for its fleet of Lockheed Martin F-35As in 2016, according to a new report issued by the Department of Defense on 31 May.
In its report to Congress, the Pentagon states that if its current plan holds firm, IOC for the largest Joint Strike Fighter customer could be achieved between August and December that year.
The USAF's criteria for IOC consists of being able to stand up the first operational F-35A squadron equipped with 12 to 24 aircraft and with enough trained personnel "to conduct basic close air support, interdiction, and limited suppression and destruction of enemy air defence operations in a contested environment".
However, the 2016 deadline does indicate a departure from the service's earlier insistence that it would require the fighter to have the full capabilities of its final Block 3F configuration to declare IOC.
That software block is expected to be complete in the latter half of 2017, according to the Pentagon's most recent indication.
Instead the air force is likely to declare IOC with either the earlier Block 2B software load or with Block 3i, which is the same configuration rehosted on newer avionics hardware.
Although the USAF says the earlier software configurations will "provide sufficient initial combat capability", it will still require the "enhanced lethality and survivability inherent in Blocks 3F and beyond" at a later date.
The US Marine Corps, meanwhile, is sticking to its plan for IOC with the Block 2B configuration between July and December 2015.
USMC will declare IOC when the first squadron of between 10 and 16 aircraft is trained and ready to conduct a broad spectrum of mission types.
The USMC also requires the jet's Autonomic Logistic Information System V2 software to declare IOC. As with the USAF, the Marines require Block 3F for their future needs, the report says.
The US Navy, however, is holding firm on requiring the full Block 3F configuration for its F-35C IOC date, which it anticipates in late 2018 or early 2019. The USN says it must have the Block 3F configuration to deal with threats in the post-2018 environment.
USN F-35C IOC is expected to be declared when the first operational squadron of 10 aircraft is manned, trained, and equipped to conduct its assigned missions.