Q&A with Boom test pilot Chris "Duff" Guarente: 3,600 hours in 57 aircraft types

“The number one trait that makes a good developmental test pilot is being humble. Long before you are flying the first flight of a new aircraft, you are helping to make engineering design decisions that will affect the way you fly and test the airplane.” — Chris “Duff” Guarente

When your job makes flying safer for everyone, there’s real satisfaction in a day’s work. Boom test pilot Chris “Duff” Guarente can attest to this statement. He’s motivated by the potential of his work to develop new aerospace technologies while simultaneously improving safety and performance. And as one of two test pilots for XB-1, Boom’s supersonic demonstrator, he’s playing an instrumental role in bringing supersonic commercial flight back to aviation.

Being a test pilot today is markedly different than aviation’s early days, when the risk of injury or death was extreme. Legends such as John Glenn, Jimmy Doolittle, Chuck Yeager and Scott Crossfield faced immense risks every time they stepped into the cockpit.

The role of test pilots has also changed. Today, test pilots are more likely to lend their expertise to the design and build of aircraft years before first flight. They play an instrumental role in human factors evaluation, ergonomics testing and mission-critical events such as wing bend tests. In the case of XB-1, Duff has lent his expertise to design and testing since day one.

A former Air Force pilot, Duff has flown more than 3,600 hours in 57 aircraft types, including more than 150 hours of combat time. He’s a graduate of the United States Air Force Test Pilot School and served as an F-22 and F-16 test pilot. Following his military career, he was chief test pilot at Scaled Composites, where he was the pilot for the first flight and envelope expansion of the Scaled Composites Swift Jet Demonstrator. Most recently, he was one of two test pilots flying the historic Stratolaunch first flight.

We caught up with Duff to learn more about his career mastering new aircraft.

What inspired you to become a test pilot?

From a young age, I loved planes. I started flying when I was 13 years old after my parents took me to fly with the EAA Young Eagle program (created by the US Experimental Aircraft Association) at New Garden Airport in Pennsylvania. From there I couldn’t stop flying. I flew throughout college and then into the Air Force for pilot training. I always loved when I had the chance to fly something new. Once I completed F-16 training, I began to look at the path ahead.

In test pilot school, I found a way that I could not only get to fly new things, but I could be instrumental in bringing new technology upgrades or even entirely new airplanes to my friends at the operational fighter squadrons across the Air Force. So, I worked to finish my Masters and build my instructor pilot hours and my flight hours in the F-16 so I could apply to the competitive yearly Test Pilot Selection Board.

Should test pilots have any specific traits?

The number one trait that makes a good developmental test pilot is being humble. Long before you are flying the first flight of a new aircraft, you are helping to make engineering design decisions that will affect the way you fly and test the airplane. You begin to plan for what happens if things don’t work the way they were designed or if you have an in-flight emergency.

If you believe that you can handle any situation with pure pilot skill, then you will not design as safe of an airplane, or one that will help you come home safely. If you understand you are fallible you will help build protections into the aircraft, and you will assume that you will take the wrong action in-flight. These assumptions help you better support the ultimate end user by designing safety mitigations into the airplane design and your test procedures.

What’s the goal of attending Air Force Test Pilot School?

The purpose of test pilot school is to train pilots that can adapt quickly to new situations and aircraft, and to ensure that you can be the connection between the operational pilots and the engineering side of aircraft development. To that end, Test Pilot School is half aerospace/flight engineering courses and half flying new and interesting aircraft to collect data.

The most exciting part of Test Pilot School is that you get to fly very different airplanes from what you have flown before and with only a brief introduction to the aircraft systems and performance. This ensures that you are learning the new aircraft from the second you sit in it and try to get strapped in. The engine start, the taxi, the takeoff, the landing are all different from what you have seen before and you have to very quickly adapt to the new environment.

What aircraft did you fly at test pilot school?

I had the privilege of flying 28 different aircraft in my year at Test Pilot School, from the MiG-15 to the F-15E, to the KC-135 tanker to the Goodyear blimp. They all taught me something new and showed me something I had not seen before. All of these experiences helped me prepare to be the first person to fly a new aircraft on its first flight.

Above and beyond first flight

The contributions of test pilots reach far beyond design, ground tests and first flight. Test pilots combine skills as aviators with deep knowledge of engineering, bringing a unique perspective to the production of new aircraft.

Boom’s test pilots, who have a deep working knowledge of multiple aircraft, translate their experience working with the aircraft into feedback for the engineering team. At Boom, their daily roles run the gamut from testing ergonomics in the hangar to flying the simulator. And, as first flight approaches, that means traveling with XB-1 to the Mojave Desert to guide the process — and to make supersonic history.