A Clean, Pristine Military Machine: The KC-46


On May 5–6, 2022, Airmen from the 22d Air Refueling Wing, McConnell Air Force Base, KS, completed one of Air Mobility Command’s (AMC) longest duration refueling flights in history: a 24.2-hour flight on one of the Air Force’s newest tankers—the KC-46 Pegasus. The flight, which spanned more than 9,000 miles (along both U.S. coasts), demonstrated the impressive capabilities of the mighty aircraft.

The Boeing KC-46 was selected as the U.S. Air Force’s next tanker in the KC-X tanker competition in 2011. Boeing delivered the first KC-46 to the Air Force in 2019, with plans to complete the fleet of 179 aircraft by 2029.

Lt Col Joshua Renfro, deputy lead of the KC-46 Cross Functional Team and a former KC-135 pilot, gave insight into the aircraft’s capabilities and the status of the tanker’s acquisition—and why he has concluded that the KC-46 is the right tanker for the future fight.

“The KC-46 is at an exciting place right now,” Renfro said. “It is the next generation tanker that we are fielding, and it is the designated replacement for the aging KC-10 fleet.”

The modern tanker thankfully can provide similar capabilities as the KC-10 and KC-135 to the joint force, Renfro informed The Mobility Forum.

“However, the KC-46 is generations beyond those tankers in terms of aircraft design. It is a clean, pristine, military aircraft,” Renfro stated.

According to Renfro, the aircraft also has a suite of capabilities that extend beyond that of a tanker and allow for it to carry out multiple mission sets.

Among these capabilities, one worth highlighting is the tactical systems it brings to AMC—it can access Link 16 and the Joint Range Extension Applications Protocol (JREAP) data link. According to Boeing, “Link 16… integrates the JREAP data onto new, full-color displays with intuitive symbols and moving maps.” Renfro explained that these tactical systems increase threat awareness so the tankers can be closer to the fight to deliver more fuel where needed. “This helps your fighters get into the fight that much faster,” Renfro said.

According to AF.mil, more of the tanker’s capabilities include:

  • Multi-point simultaneous aerial refueling through two refueling receptacles (one on each wing).
  • The capability to operate quickly and effectively at smaller, forward airfields, which often have shorter, narrower runways, little ramp space, and fewer on-the-ground resources.
  • Fueling offload rates required for large aircraft.
  • A hose and drogue system that adds additional mission capability that is independently operable from the refueling boom system.
  • The space to accommodate a mixed load of passengers, aeromedical evacuation, and cargo.
  • A number of self-protection, defensive, and communication features making it more survivable in a contested environment.

Although the tanker provides many military capabilities, it did not initially come fully equipped. Renfro explained that the tanker, based on the Boeing 767 2C model, is not sold commercially; it is a commercial variant produced solely for the military. By acquiring this type of aircraft, the Air Force saves significant time in the research and development phase making it one step closer to readiness.

“You are modifying it to meet your mission needs and then putting it out under what should be lower costs and faster fielding,” Renfro said. “I believe that is true, but it also carries its own challenges.”

Some of these challenges have included refining the aircraft’s camera system, so the tanker is fully mission capable. Camera system technology, not previously used in aerial refueling, brings a learning curve. Boeing and Air Force engineers have joined forces to find solutions for common camera problems such as sun angles and low clouds.

These advancements led to the fielding of an Enhanced Remote Visual System (eRVS) to correct flaws in the former system. The final product will reduce eye strain on the operators by letting them adjust their sight picture to fit their physiological needs.

“We were out at Boeing last week, and it is phenomenal the difference it [RVS 2.0] makes,” Renfro said. “The eRVS is a minor fix, but the first major fix coming down the pipe will be RVS 2.0, which is a comprehensive re-work that will upgrade the cameras to the current technology levels, removing most of the current restrictions on employment.” The second issue identified is the current boom design. This boom lacks the dynamic stiffness needed in refueling, limiting the ability to refuel thrust-limited aircraft. The fix for this challenge is a boom telescope actuator redesign. “After these fixes, we end up with essentially the tanker we wanted to begin with, without those system-induced limitations that are caused by the original design of it,” Renfro said.

The robust test processes that the Air Force employs have been critical in making the KC-46 “today’s tanker.” Renfro continued giving insight into these processes. “Boeing has its own test processes,” Renfro noted. Following those processes, he explained that when the Air Force obtains an asset, it goes through a developmental test (DT). “Test pilots and test booms put it through the paces: heavyweights, lightweights, hot, cold, heavy receivers, light receivers, in turns, in clouds, turbulence, and more.”

The DT process generates deficiency reports, and Air Force engineers then work with Boeing engineers to identify the causes of any issues. This process, which every incoming aircraft to the Air Force goes through, helps identify and solve the main challenges previously discussed, plus a few additional issues, such as cargo operations and passenger considerations.

After the DT process identifies the safety parameters, operational tests take place in which non-test pilots use the tanker and give their unique insight. This practice adds an additional layer of safety.

Renfro believes these processes are essential to the current achievements and future success of the KC-46. The tanker’s reputation may have been marred by what some view as setbacks, but delays are often part of the nature of fielding. “It is not dissimilar than what we saw with the C-17 when it was coming up,” Renfro said. “I think the big misconception that we have now [regarding the KC-46’s “slower” fielding] is because there are very few people in the Air Force who have ever seen a modern weapon system come online. It is easy to say that this process is taking a long time and that it is not delivering flawless out of the box; it is not, but neither has any other aircraft. As aircraft get more and more complicated, that will continue to be the case with future generations.”

Renfro is close to all aspects of the KC-46 advancement, being a deputy lead of the KC-46 Cross Functional Team, which is a specific, staff-created entity. Because the Air Force needed to upgrade the aircraft into a fully combat-capable product, it then created a series of teams to provide a singular focus on various plans and work with Boeing engineers to make them happen.

Renfro credits his predecessor, Lt Col Kevin White, for his integral role in advancing the KC-46. He also praised the work of Gen Ryan Samuelson, the Cross Functional Team lead, and Capt Michelle Kuyper, the action officer.

Renfro says this team works across the entire enterprise that works with the KC-46 to align the stars and figure out what needs to happen next. They also report regularly to Gen Mike Minihan, AMC Commander, to highlight how the systems are progressing.

Renfro explained that their progress has been through the Interim Capability Release effort, which started in July 2021 and was completed in September 2022. This program accesses what the tankers can do now. Identifying what it can do now can bolster its progress. This approach to advancing the KC-46 is measured, deliberate, and risk-informed. Since starting these modifications, the KC-46 has made huge strides of improvement, going from being operationally tasked against no receivers to being cleared to refuel every receiver aircraft with a technical compatibility with the KC-46 except for the A-10. In fact, Minihan declared the KC-46 worldwide deployable at Air & Space Forces Association’s Air, Space & Cyber Conference in September 2022.

Renfro’s message to Airmen is that “sometimes it is hard to see what is going on. It may feel as if the process is taking forever, but all the actions of the Airmen involved have made tremendous progress. The data collection, essential to progress and improvement, is powered by Airmen.”

A self-proclaimed skeptic when approaching new ideas, Renfro says he has been blown away by witnessing the tanker come to life.

The phrase “it’s the journey, not the destination” may be overused, but it rings true for a reason. For the KC46, the exemplification of leadership and safety layers has been incredible. Whereas its capabilities will be tremendous, the walk up the chain was deliberate and informed by the field and has shown what AMC Airmen are capable of when working together.

Today’s tanker needed to be safer and more innovative, and the KC-46 is just that—thanks to all those involved.