Reverse air refueling proof of concept
An aircrew from the 22nd Airlift Squadron (part of the 60th Air Mobility Wing at Travis Air Force Base, California) conducted a reverse flow air refueling training with a C-5M Super Galaxy and a KC-10 Extender over Northern California and Oregon, on Dec. 12, 2023.
The reverse air refueling is a proof of concept, designed to maintain readiness in emergency situations to prevent loss of a tanker aircraft.
“By using a C-5 as a huge floating gas station, it allows more tankers to be positioned for offloading to fighter or mobility aircraft, versus having to use one tanker to refuel another, which takes away a tanker asset from the mission,” said US Air Force (USAF) Maj. Justin Wilson, 22nd AS chief of standards and evaluations and C-5M evaluator pilot, in the article Team Travis flyers conduct reverse flow air refueling by Senior Airman Alexander Merchak, 60th Air Mobility Wing Public Affairs. “This allows more tanker aircraft in the theatre and extends their range or orbit time.”
The C-5M Super Galaxy strategic transport aircraft
The C-5M Super Galaxy is a strategic transport aircraft and is the largest aircraft in the Air Force inventory. Its primary mission is to transport cargo and personnel for the Department of Defense. The C-5M is a modernized version of the legacy C-5 designed and manufactured by Lockheed Martin.
The C-5M, with a cargo load of 281,001 pounds (127,460 kilograms), can fly 2,150 nautical miles, offload, and fly to a second base 500 nautical miles away from the original destination — all without aerial refueling. With aerial refueling, the aircraft’s range is limited only by crew endurance.
According to Wilson, this was the first time the C-5M was used like this since its initial testing and certification. By conducting tests on this procedure, the aircrew successfully gathered data points that can be utilized in the future to enhance the range and capabilities of a tanker aircraft.
According to Alert 5, the groundbreaking mission not only demonstrated the aircraft’s adaptability but also underlined the importance of incorporating unconventional procedures to meet evolving mission requirements.
C-5M offloading 23,500 pounds of fuel to KC-10
“By doing reverse air refueling, the aircraft is getting lighter at a quicker rate than if you were just flying normally, so the aircraft flies a little different,” said Wilson. “The real difference is when it comes to the flight engineers.”
“To execute the reverse air refuel, we made amendments to two of our normal checklists,” said Tech. Sgt. Robin Ogg, 60th Operations Group C-5M senior evaluator flight engineer. “These changes were in the flight engineer’s fuel panel configuration to set us up to give fuel versus receiving it.”
An in-flight refuel normally consists of a KC-10 or KC-46A Pegasus delivering fuel to another aircraft. In this exercise, the C-5M aircrew reversed the process with the help of a KC-10.
“This mission on the C-5 meant showcasing precision, teamwork, flexibility, and adaptability,” said Ogg. “It highlighted the importance of trust and coordination within the team, emphasizing everyone’s crucial role. The experience left me with a deep sense of pride and accomplishment.”
The C-5M offloaded 23,500 pounds of fuel in approximately thirty minutes to the KC-10.
Photo by Senior Airman Alexander Merchak and Master Sgt. Traci Keller / U.S. Air Force
