The US Air Force’s aircraft capacity falls short of being able to meet a variety of long-term future scenarios, including a new cold war with Russia or China, according to an analysis by Rand Corp.

The think tank examined the USAF’s fleet and the likely demands placed on it under four future scenarios: two scenarios in which the USA enters a new cold war with Russia or China; one in which it renews peace enforcement commitments like those between 1990 and 2000; and one in which military operations are dominated by global counterterrorism and counterinsurgency operations, such as they have been since 11 September 2001.

In all four scenarios examined the USAF has capacity shortfalls, with no single class of aircraft, such as fighter, bomber or airlift aircraft, performing sufficiently across all possibilities. Fighter aircraft came closest to meeting capacity requirements, and C3ISR/BM (command, control, communications, intelligence, surveillance, and reconnaissance/battle management) aircraft had the biggest shortfalls, reflecting their small fleets and high demand, Rand Corps says.

The USAF’s fleet of aircraft is stretched thin by obligations the world over, the researchers write in the report.

“With no end in sight to operational demands in the Middle East and South Asia and growing concerns about the changing military balance in Europe and Asia, the USAF must continue to provide forces to meet combatant commander requirements while training and equipping the force to meet rapidly evolving conventional threats,” says the report. “These dual challenges stress both the capacity and capability of USAF force structure.”

And, even if the USAF significantly increased the time its aircraft and personnel were deployed to war zones and potential conflict areas, reducing the time they were stationed at home for maintenance and rest, their still would not be enough capacity to meet demand, the report adds.

The Rand Corp. report comes as the USAF’s number of aircraft have declined precipitously over the past three decades, partly the result of a Cold War draw down in aircraft purchases and a greater emphasis placed on buying fewer, more expensive aircraft, such as the Lockheed Martin F-35 which promise greater capabilities. To offset this shrinking force the service has been experimenting with so-called Loyal Wingman drones, including Kratos Defense’s XQ-58A Valkyrie, which will be test flown for the first time this fall.