Dec. 31 (UPI) -- Lockheed Martin closed out the calendar year with $2.35 billion in five new contracts for the F-35 program.
The F-35 Lightning II Joint Strike Fighter -- a single-engine stealth multirole combat aircraft used by the U.S. Air Force, Navy, and Marine Corps -- is considered the most advanced fighter aircraft in the sky, as well as a notable driver of the Pentagon's budget.
The largest contract on the DoD's list, for $1.93 billion, funds recurring logistics services -- including ground maintenance and supply chain management -- for F-35 Air Systems in the Air Force, Marine Corps, Navy and foreign military sales customers.
A second contract, for $172.2 million, funds materials procurement for 28 lot 15 F-35 aircraft for the Navy and Marine Corps.
A third provides $98.9 million in funding for a previously issued ordering agreement for next-generation sensor systems for all variants of the F-35 aircraft for the Navy, Marine Corps, Air Force and non-Department of Defense participants.
The DoD also awarded an $81.97 million modification to a previously awarded contract for software development for the F-35 Lightning II in support of the Air Force, Navy, Marine Corps and non-Department of Defense participants.
Lockheed also a nabbed $68 million contract modification to identify and correct potential process issues for F-35 operation cards used by the Navy, Marine Corps and Air Force.
On Monday Lockheed announced that it had delivered its 134th F-35 fighter plane, exceeding its goal of 131 for the year.
An August Pentagon report said the cost of the F-35 program grew by $25 billion in 2018 and was the main driver of a 4 percent increase in the Pentagon's budget. That increase was attributed to upgrades to the planes and programs, higher expenses in deploying the planes and costs associated with modifying the planes to carry nuclear weapons.
Lawmakers have continued to criticize the F-35 program, declining in November to extend a multiyear contract for the jets due to shoddy parts and failures of the maintenance system.
That criticism came just weeks after Lockheed signed a $34 billion deal to deliver 478 F-35As to the military at a cost below $80 million per plane.
That deal marked both the lowest per-plane price Lockheed has promised in the nearly-30-year history of the F-35 program, and the largest single procurement in Pentagon history.
The increase is, in part, because of upgrades to the planes and programs, known as Block 4, which modify existing planes with new systems and weapons as new threats are recognized. The modifications are also added to planes in production.
Overall costs include the Block 4 modifications, designing F-35s to carry nuclear weapons, increased use of onboard software, and higher expenses of deploying the planes.