The F-35 fighter's long road toward deployment has hit a new, unexpected bump.
The Lockheed Martin plane can't tolerate fuel that exceeds a certain temperature. That has created problems at facilities including Luke Air Force Base in Arizona, where summer temperatures can exceed 110 degrees.
The Air Force base public affairs office told CNBC that crews testing the state-of-the-art jet fighter discovered the problem and are trying to solve it. One solution being tried is to repaint fuel trucks with white, reflective paint in order to keep the fuel inside cooler.
Luke is one of seven bases testing the F-35 and beginning pilot training. Fuel trucks near runways do not have any shade from the sun, driving up temperatures of the fuel inside. Rather than try to modify the already expensive jet, the Air Force reports that it is painting four trucks at a cost of $3,900 each.
So far, only one truck has been repainted. Whether the new paint solves the problem is still being determined. The idea has also reportedly been tested at Edwards Air Force Base in Southern California, another area where the heat hits triple digits.
The new paint job "ensures the F-35 is able to meet its sortie requirements," Chief Master Sgt. Ralph Resch, fuels manager at the 56th Logistics Readiness Squadron, told base public affairs in an item posted on the Air Force website. "We are taking proactive measures to mitigate any possible aircraft shutdowns due to high fuel temperatures in the future."
A potential problem with repainting is that bright white paint could make trucks easier targets if they were based in hostile territory subject to high temperatures, such as deserts. Temperatures in Iraq, for instance, can exceed 120 degrees.
"The long-term fix is to have parking shades for the refuelers," Resch said. The Air Force is also testing the idea of maintaining fuel trucks' traditional green color and instead covering them with a heat-reflective coating.
CNBC contacted Lockheed for more information on temperature limits for the F-35's fuel, and whether this presents yet a new hurdle for a program plagued with hiccups and cost overruns. Lockheed had not yet responded by publication time of this article.
Lockheed last month signed a $4.7 billion deal for 29 more of the aircraft for the United States and five close allies. It's anticipated that eventually 200 of the aircraft will be in operation in eight countries.
This article originally appeared in CNBC.
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