SCOTT AIR FORCE BASE, Ill. — The U.S. Air Force is set to complete a major upgrade of its C-21 fleet in 2020, officials told Defense News.

The service operates a total of 19 C-21 aircraft, a militarized version of the Learjet 35A business jet used primarily for executive transport.

The Air Force intends to spend about $38 million to refresh the planes’ avionics suite, including replacing the analog cockpit with a digital version and adding a suite of new systems that allow it to meet Federal Aviation Administration requirements.

Eleven C-21s have gone through the modernization process, with the remaining eight jets set to go through the process by July 2020, said Maj. Kirk Schlueter, the 375th Operations Group chief of standards and evaluations.

Schlueter spoke with Defense News during a December visit to Scott Air Force Base, Illinois, which owns a total of 14 C-21s after four jets from Andrews Air Force Base were transferred to the 458th Airlift Squadron in June. The other five aircraft are operated by the 86th Airlift Wing at Ramstein Air Base, Germany.

The avionics upgrades include a new weather radar, flight-management system and certain FAA-required air traffic control systems like ADS-B. Those improvements open up the number of approaches available to pilots while landing, and also allow the aircraft to fly at higher altitudes.

While designing the new digital cockpit, the Air Force modified the layout of flight instruments and displays to make it more similar to other military aircraft, which will help ease the transition for young pilots moving from the C-21 to other Air Force planes.

"I actually flew with about a 70- year-old Lear[jet] guy last week, and he goes: ‘Your instruments are backwards.’ And I said: 'Yeah, that’s how we wanted it,’ ” Schlueter said.

While usually used by military officials for travel, C-21 operators pride themselves on offering a more rugged form of transport, as the jet is outfitted to perform aeromedical evacuation and regularly spends time over the skies of the Middle East.

One of Scott AFB’s jets is usually deployed to Al Udeid Air Base in Qatar at any given time to provide a flexible transportation option to military leaders needing to move quickly to bases around U.S. Central Command’s area of responsibility, said Lt. Col. Brooke Matson, commander of the 458th Airlift Squadron.

“We offer the most precious of resources that NetJets or Delta can never offer. Our pilots go into combat zones,” she said. “Our airplane is small and nimble and can go into contested environments — degraded GPS, for example. We have equipment on our aircraft that the average commercial airplane does not have, like military GPS."

Usually, four aircrew and nine maintainers deploy to CENTCOM to operate and support the C-21, and the aircraft are swapped out one or two times per year, Matson said.

Valerie Insinna is Defense News' air warfare reporter. She previously worked the Navy/congressional beats for Defense Daily, which followed almost three years as a staff writer for National Defense Magazine. Prior to that, she worked as an editorial assistant for the Tokyo Shimbun’s Washington bureau.

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