With the delivery of four Lockheed Martin F-35 Lightning II aircraft since June 29, an important milestone was achieved as the Department of Defense now possesses more operational-coded F-35s than test aircraft. A total of nine F-35s have been delivered for the year, giving the DOD a total of 30 aircraft fleet-wide. Of these, 16 are operational aircraft and 14 are test planes.

"To date, the F-35 program has focused on system development and flight testing while most recently transitioning to low rate initial production," said Orlando Carvalho, Lockheed Martin executive vice president and general manager, F-35 program.

"We've crossed a critical threshold as we begin delivering our LRIP 3 aircraft. We're increasingly becoming more operationally focused. These deliveries illustrate the program's natural progression and maturation that is taking place on a daily basis."

The four aircraft, which were formally accepted by the Defense Contract Management Agency with the signing of Department of Defense Form 250 (DD-250), are the first jets manufactured as part of Low Rate Initial Production (LRIP) Lot 3.

They will begin ferrying to Eglin Air Force Base, Fla., in the coming days, bringing the total there to 16. The DOD has eight test aircraft at Naval Air Station Patuxent River, Md., and six test aircraft at Edwards Air Force Base, Calif.

Three of the jets are F-35A conventional takeoff and landing (CTOL) variants and will be assigned to the U.S. Air Force's 33d Fighter Wing.

One F-35B short takeoff and vertical landing (STOVL) aircraft will be assigned to the 2nd Marine Aircraft Wing's Marine Fighter/Attack Training Squadron 501. Once at Eglin, the 5th Generation fighters will be used for pilot and maintainer training at the base's F-35 Integrated Training Center.

The F-35 Lightning II is a 5th Generation fighter, combining advanced stealth with fighter speed and agility, fully fused sensor information, network-enabled operations and advanced sustainment.

Three distinct variants of the F-35 will replace the A-10 and F-16 for the U.S. Air Force, the F/A-18 for the U.S. Navy, the F/A-18 and AV8-B Harrier for the U.S. Marine Corps, and a variety of fighters for at least nine other countries.