Members of Congress want to nix the U.S. Air Force’s plans in its latest budget request to replace two U.S. Air Force OC-135B surveillance aircraft and have proposed a provision that would make it illegal to do so until Russia returns to compliance with the Open Skies Treaty. That agreement, which allows both countries and other parties to legally fly aerial reconnaissance missions over other member states’ military facilities, has become increasingly controversial, but sticking with the old planes could put American crews at risk and would seem to put the United States at an inherent disadvantage in capability. On May 9, 2018, in a session to amend and approve the latest draft version of the National Defense Authorization Act for the 2019 fiscal year, the formal title for the annual defense budget, the House Armed Services Committee removed the more than $222 million the Air Force had wanted in order to buy a pair of new aircraft to take on the Open Skies mission. The Committee and other assembled legislators approved the new version of the bill, which does retain nearly $6 million for upgrades to the two existing OC-135B aircraft, in a 60-1 vote. The funding allocations could change again in the future as the House and the Senate work to align their respective versions of the law before putting the final iteration up for a formal vote.

“Russia has violated key arms control treaties, expanded and modernized its nuclear arsenal, tested counter-Space weapons, and used emerging technologies to undermine its neighbors,” a statement that the House Armed Services Committee released after the so-called markup said. As such, Committee Chairman, Texas Republican Mac Thornberry was “withholding funding for Open Skies Treaty aircraft and sensors until Russia again complies with the Treaty and takes other steps, including agreeing to extradite Russian nationals who have been indicted for their actions against the United States during the 2016 election.” The Open Skies Treaty entered into force in 2002 and presently includes 34 member states. The agreement allows any of them to fly limited surveillance missions over the territory of another with prior notice using aircraft equipped with relatively low-definition, visual cameras.

USAF One of the two OC-135B Open Skies aircraft.

The ostensible goal of the deal is to improve transparency regarding peacetime military activities. The underlying concept is that if member states can directly observe and verify the nature of maneuvers and internal deployments and redeployments in neighboring countries, they are less likely the fear that these developments are actually a prelude to a sneak attack or other malign actions. This, in turn, is supposed promote stability between countries that might otherwise be skeptical of each others’ true motives. To help enforce the treaty and provide the U.S. government with a capability to exercise its rights under the agreement, the U.S. Air Force’s 55th Wing at Offutt Air Force Base in Nebraska operates two specially configured OC-135B aircraft. The Defense Threat Reduction Agency, a U.S. government agency charged with both monitoring developments regarding weapons of mass destruction and also working to reduce the threat of conventional conflict, provides a portion of the crew during the actual mission.

USAF via FOIA A redacted breakdown of the various locations supporting the Open Skies mission, including main and forward operating bases, as of 2010.

But the OC-135Bs are among the oldest aircraft in the 55th Wing and are likely some of the oldest in the Air Force as a whole. These planes rolled off the production line in 1961 as C-135B Stratolifter cargo aircraft. The service subsequently converted them into WC-135B weather reconnaissance planes, before turning them into their present configuration. So, in its fiscal year 2019 budget proposal, the Air Force has asked for funding to buy two new “small airliner class aircraft” to replace them. It’s not entirely clear what type of planes the service had in mind, as the description could apply to more traditional commercial-type passenger aircraft, such as varied as the Boeing 737, or increasingly popular business jet-sized designs such as the Gulfstream G500 and G600 series or the Bombardier Global Express.

USAF A US Air Force C-40 personnel transport, which is derived from the Boeing 737 airliner.

If the Air Force determined it could fit the necessary equipment and crew into a bizjet-sized platform, it could have offered a particularly cost-effective replacement for the larger, but aging OC-135Bs. The service already operates various types based on the Gulfstreams, including plans to purchase new variants as an electronic warfare aircraft, as well as the Global Express-based E-11A Battlefield Airborne Communications Node (BACN), which could have further reduced operating and logistics costs. At the same time, it and other branches of the U.S. military fly militarized 737s, which might have made that an attractive option, too. If nothing else, the Air Force had rightly determined that it needed some sort of replacement for the increasingly obsolete OC-135Bs sooner rather than later. These planes use four Pratt & Whitney TF-33 turbofans, an inefficient low-bypass design that first entered production in 1959 and that the company hasn’t made since 1985. Their predominantly analog mission systems and other onboard equipment are increasingly unsupportable, as well.

USAF A US Air Force E-11A Battle AIrborne Communication Node aircraft, which is a modified Bombardier Global Express.