The Lockheed Martin F-35 Lightning II has started Initial Operational Test and Evaluation (IOT&E) under supervision of the Director of Operational Test and Evaluation (DOT&E).

The IOT&E process will measure the effectiveness, suitability, lethality, survivability and overall mission capability of the aircraft, says the F-35 Joint Program Office. Through late summer 2019, all three variants of the F-35 will be field tested under realistic combat conditions for the purposes of determining the stealth fighter’s operational effectiveness and suitability for combat.

The Joint Strike Fighter Operational Test Team began some pre-IOT&E events such as cold weather operations, weapons demonstrations, suitability deployments and lower threat missions earlier in 2018, says the Joint Program Office. Formal IOT&E is intended to test the system and identify areas for improvements.

“The F-35 enterprise will work together to understand and holistically address any findings,” says the Joint Program Office. “Following the evaluation and the DOT&E report provided to Congress, the US Government will have data to inform its ‘Milestone C’ decision, leading to formal entry into full rate production.”

Ultimately, the Pentagon aims to buy some 2,456 copies of the F-35. However, IOT&E must be completed before the Department of Defense is legally allowed to start full-rate production to acquire the F-35 in large batches. Once started, full-rate production would guarantee multi-year orders to Lockheed Martin, which then could pass back a bulk discount to the US government.

Apparently in anticipation of successfully completing IOT&E, Lockheed Martin in November won a $22.7 billion contract from the Joint Program Office to supply 255 F-35 Lightning II stealth fighters for the three branches of the US armed services and international operators. The deal covers production into 2023.

There are already more than 340 F-35s operating from 15 bases around the world, for the US military branches and international partner nations. And the US Marine Corps’ F-35B made its combat debut in Afghanistan in September.