The US military's potentially trillion dollar F-35 program has reliability problems that could hobble fleet readiness and balloon its cost even further, according to a Department of Defense testing office assessment seen by Bloomberg News.

The assessment states that the supply chain for spare parts hasn't kept up with demand, and that the parts have proven less reliable than expected. As a result, up to 20 percent of the jets must sit vacant awaiting spares, hobbling the ability of squadrons to train in the jets.

Over the lifetime of the F-35, which includes buying, developing, and maintaining it for decades, it could cost the US upwards of $1.2 trillion, according to the assessment.

Despite the F-35's Autonomic Logistics Information System (ALIS), which tracks wear and tear on individual components and even orders new parts when needed, the testing offices say the “life cycle costs�? of the aircraft are “likely to increase significantly.�?

Lockheed Martin, the jet's manufacturer, has pressed the Pentagon and investors for larger block buys to allow economies of scale that would reduce the prices associated with the jet and its components, but the assessment, dated May 8, seems to cast doubt on whether or not the US Air Force, Navy, and Marine Corps can actually afford the 2,443 F-35s they plan to purchase.

Read the full story at Bloomberg here >

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