The new MQ-25 unmanned tanker achieved the important milestone by refueling a U.S. Navy F/A-18F over Illinois.
The MQ-25 Stingray performed the first ever air-to-air refueling operation between an unmanned tanker and a manned receiver aircraft, in this case a U.S. Navy F/A-18F Super Hornet. The successful test happened on June 4, 2021, with the Boeing-owned MQ-25 T1 test asset flying from MidAmerica Airport in Mascoutah (Illinois) and employing the Cobham Aerial Refueling Store (ARS), the same used by F/A-18s, to perform the refueling operation.
“This flight lays the foundation for integration into the carrier environment, allowing for greater capability toward manned-unmanned teaming concepts,” said Rear Adm. Brian Corey who oversees the Program Executive Office for Unmanned Aviation and Strike Weapons. “MQ-25 will greatly increase the range and endurance of the future carrier air wing – equipping our aircraft carriers with additional assets well into the future.”
History in flight! During a recent #MQ25 T1 test asset flight, this unmanned aerial refueler for the @USNavy delivered fuel to an F/A-18 #SuperHornet — the first time an unmanned aircraft has ever refueled another aircraft. pic.twitter.com/oDs9Y2uQdQ
— Boeing Defense (@BoeingDefense) June 7, 2021
During the flight, as disclosed by NAVAIR, the Super Hornet approached the MQ-25 while conducting a preliminary formation evaluation, wake survey and drogue tracking, before receiving the green light to go ahead and plug its probe in the ARS’s drogue deployed by the unmanned aircraft. According to the press release, the MQ-25 performed a “wet refueling”, effectively transferring fuel to the F/A-18 (as opposed to a “dry refueling” where there isn’t fuel transfer after contact, often used during test and training flights).
Some more details were provided by Boeing, specifying that the F/A-18 flew in close formation behind MQ-25 to ensure performance and stability prior to refueling, with as little as 20 feet of separation between the two aircraft, while flying at operationally relevant speeds and altitudes. After the safety evaluation, the MQ-25 drogue was extended and the F/A-18 pilot was cleared for the refuel. The MQ-25 T1 performed so far 25 flights, which were integrated by extensive digital simulations of aerial refueling.
“This is our mission, an unmanned aircraft that frees our strike fighters from the tanker role, and provides the Carrier Air Wing with greater range, flexibility and capability,” said Capt. Chad Reed, program manager for the Navy’s Unmanned Carrier Aviation program office (PMA-268). “Seeing the MQ-25 fulfilling its primary tasking today, fueling an F/A-18, is a significant and exciting moment for the Navy and shows concrete progress toward realizing MQ-25’s capabilities for the fleet.”
This test flight provided important data on airwake interactions, as well as guidance and control, that will be analyzed to determine if any further adjustments are needed to improve the Stingray’s software before moving on with the program’s test schedule. The testing with the MQ-25 T1 will continue over the next several months to include flight envelope expansion, engine testing, and deck handling demonstrations aboard an aircraft carrier later this year. For the latter, the MQ-25 will be moved to Norfolk (Virginia).
The MQ-25 T1 flew for the first time with the Cobham ARS under its left wing in December 2020, about one year after the drone’s own first flight, testing how the aircraft’s aerodynamics changed with the addition of the ARS. The following flights contributed to test the aerodynamics of the aircraft and the ARS at various points of the flight envelope, before progressing to the extension and retraction of the hose and drogue used for refueling that paved the way for the first air-to-air refueling.
As we already reported, the MQ-25 T1 is the predecessor to the four engineering development model (EDM) MQ-25 aircraft being produced, the first of which is expected to be delivered later this year. The U.S. Navy is planning to procure more than 70 aircraft, which will replace the F/A-18E Super Hornets in the aerial refueling role they currently have as part of the Carrier Air Wing, becoming also the first operational carrier-based UAV. This way, the Carrier Air Wing will have more Super Hornets available for operational mission, without the need to reserve some of them for the air-to-air refueling mission.