MELBOURNE, Fla. — The U.S. Air Force may have prioritized growing research and development in its fiscal 2018 budget request, but its unfunded wish list is all about buying more aircraft — namely more F-35s and KC-46s.

Of the service's $10.7 billion unfunded priorities list submitted to Capitol Hill on May 31, $6.7 billion would go toward modernization and readiness needs, according to documents obtained by Defense News. The list is usually used by members of Congress to determine where to increase funding, often resulting in increased procurement of high-value items such as aircraft, ground vehicles and ships.

Fourteen F-35A joint strike fighters top the modernization and readiness portion of the list, ranking as the fourth biggest unfunded priority for the Air Force overall. If those aircraft are funded by Congress for an additional $1.76 billion, the Air Force will have met its target buy rate of 60 aircraft for the first time. Its current budget request includes only 46 aircraft in FY18.

"The Bipartisan Budget Act [BBA] has forced us to make sacrifices as we balance readiness and modernization," the service stated in a description of the item. "This has slowed modernization of our fourth generation aircraft. With increased funding, we would invest in these capabilities now to ensure they do not compete for funding with critical nuclear and space requirements in the out years."

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The Air Force included three KC-46As on the list, which would accelerate procurement and allow it to replace legacy tankers sooner. Further down the list, it also adds 12 MC-130Js, which, if funded, would bring FY18 procurement to 17 aircraft, as well as one additional HC-130.

To keep the Compass Call program on track, the Air Force would need an additional $284.6 million for a number of initiatives, according to the list. About $30 million would go to extend the life of the current EC-130H aircraft because its replacement program lags behind schedule. The rest would fund efforts related to the Compass Call crossdeck strategy, wherein the service will "rehost" the EC-130H's existing electronic warfare systems on a new airframe. A large part of that — $166.1 million — would go toward purchasing a third crossdeck airframe and doing the necessary integration work.

Although the Air Force included a huge hike for its future air superiority fighter jet — interchangeably called Penetrating Counter Air or Next Generation Air Dominance — in the FY18 budget, the service believes it could still use an additional $177 million for risk reduction efforts, particularly for mission systems, the air vehicle and propulsion technologies. The service requested $295 million for PCA development this year, but additional money could help speed up fielding of the aircraft.

In the area of emerging technologies, it included $70 million for directed energy, specifically to develop a "high power microwave weapon capable of multi-shot, multi-target ability to knock out digital electronic systems with low or no collateral damage and within anti-access area-denial environments." A hypersonic prototype "to accelerate a Time Sensitive Target Engagement" also made the list.

The list also includes $131.6 million for various modifications for fourth- and fifth-generation fighter jets.

Overall, the top unfunded priority for the Air Force was a variety of readiness and training shortfalls, worth $359.7 million overall. The list also included $722 million for space, and those items also ranked high. Efforts bundled as "space defense requirements" came in second at $209.3 million total, and SBIRS-related needs took third place with $125.4 million left unfunded in the budget.

Also outside of the readiness and modernization sphere, the service listed $360 million for nuclear deterrence operations, with nuclear command, control and communications emerging as a priority, and $563 million for cyberspace needs.

Valerie Insinna is Defense News' air warfare reporter. She previously worked the Navy/congressional beats for Defense Daily, which followed almost three years as a staff writer for National Defense Magazine. Prior to that, she worked as an editorial assistant for the Tokyo Shimbun’s Washington bureau.

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