Final negotiations on the fifth low-rate, initial-production (LRIP) lot of F-35 production are complete, and the last $127.7 million of that deal has been awarded to Lockheed Martin.

The total value of the contract is $3.8 billion and covers the airframe only; negotiations with Pratt & Whitney on purchasing the F135 engines for the single-engine fighter are still ongoing, according to Joint Strike Fighter Joint Program Office spokesman Joe Dellavedova.

This award marks the end of long and often contentious negotiations between the Pentagon and Lockheed Martin.

LRIP 5 will provide for 32 aircraft. This all-U.S. order includes 22 conventional-takeoff-and-landing versions for the Air Force, seven carrier variants for the Navy and three short-takeoff-and-vertical-landing versions for the Marine Corps.

The average unit cost across this buy is about $118 million, again without an engine. The program office has not yet released the cost per aircraft for the different variants. Those details are expected next week.

In recent days, Reuters had reported the Pentagon will pay about $107 million apiece, or about 4 percent less than the previous contract, for each of the 22 conventional takeoff and landing jets in the deal.

Meanwhile, program officials say that they expect to declare the F-35A training wing at Eglin AFB, Fla., ready to produce instructor pilots by year-end as earlier proposed.

Lockheed Martin officials say they expect to deliver the 30 aircraft promised in 2013 by year-end. Only 20 have been turned over to the Pentagon thus far. But, a program official says only a few check-out flights remain along with the final paperwork to officially shift ownership of the aircraft to the Defense Department.