Press Releases

Alfred University engineering student rebuilding airplane for capstone project

Alfred University | 11/08/18

Andy Diffenderfer (left), Kristofer Knapp (back) and Parker Rice work on Diffenderfer’s airplane.
Andy Diffenderfer (left), Kristofer Knapp (back) and Parker Rice work on Diffenderfer’s airplane.

It was the summer of 2017 and Andy Diffenderfer was 3,000 feet in the air, on just the third flight in his recently-acquired light sport airplane, when the engine sputtered and stalled. Keeping his head, Diffenderfer glided in circles until the aircraft touched down safely in a field near Elmira Corning Regional Airport.


ALFRED, NY – It was the summer of 2017 and Andy Diffenderfer was 3,000 feet in the air, on just the third flight in his recently-acquired light sport airplane, when the engine sputtered and stalled. Keeping his head, Diffenderfer glided in circles until the aircraft touched down safely in a field near Elmira Corning Regional Airport.

“I didn’t panic. I just flew the plane,” recalled Diffenderfer, a senior mechanical engineering major at Alfred University. “When I fly, I always ensure I have a field or clearing in sight and within glide range at all times, which saved my life and the aircraft in this circumstance.”

Diffenderfer said it is rare for aircraft to experience engine issues, since potential problems are normally detected during frequent maintenance checks. In this instance, he explained, a failed crank seal deep inside the engine caused excess oxygen to leak in and increase the temperature of the mixture, “resulting in almost immediate, total engine seizure.”

Knowing he had to address the plane’s engine problems before he could take to the skies again, Diffenderfer spent this past summer rebuilding the engine. He made a pair of flights in August and September before realizing a complete overhaul of the plane was in order.

 “I figured it was time to take it apart and see what improvements could to be made,” said Diffenderfer, who purchased his plane, a 1985 Challenger light sport with a 31-foot wingspan, in the summer of 2017. The plane, with a frame constructed mainly from aluminum tubing covered in strong, lightweight fabric, weighs about 300 pounds – 500 pounds with a pilot and fuel.

Diffenderfer brought the plane to Alfred University at the beginning of the fall semester with plans to do the overhaul, and discovered while dismantling the aircraft that some structural issues needed to be addressed. Ultimately, he decided to make the airplane rebuild his senior capstone project.

“I didn’t know it was going to be my capstone until the beginning of the semester,” he said. “Small aircraft have to be overhauled periodically, so I thought this would make a good project.”

Diffenderfer, who holds a student pilot’s license, became interested in flying while growing up in Horseheads, NY, in an area popular with recreational pilots. Prior to becoming licensed, he gained experience in flying and aircraft construction from pilots at nearby Elmira Corning Regional Airport in Big Flats, NY.

With the help of some friends – including junior Parker Rice of Buffalo and senior Kristofer Knapp of Palmyra, NY, both renewable engineering majors – Diffenderfer has torn down and begun rebuilding the plane in a room in the McMahon Engineering Building. With the engine rebuilt, work is being done to overhaul and redesign parts of the aluminum frame and other components: instrument panels, control mechanisms, etc.

The plane should be fully overhauled and ready to take flight again sometime next spring. Diffenderfer has been exposed to aircraft overhaul procedures by other sport pilots; however most of his abilities are self-taught. “Every pilot has to know how their plane works; how each part works affects the aircraft,” he explained.

It helps, too, that he is mechanically inclined.

“I have a lot of hobbies; aviation is just one,” said Diffenderfer, whose interests include woodworking and machining. He operates a small woodworking business from his home in Horseheads, where he crafts furniture and creates wood carvings. “I have a lot of projects going on. I’m never bored.”

Diffenderfer hasn’t decided on a career after he graduates from Alfred University next spring, but concedes it could be in the field of aviation.

“I’d like to get into some form of mechanical design, whether it’s parts for aviation, automotive, or manufacturing systems,” he said. “There are so many opportunities out there.”

As for his airplane, Diffenderfer plans to keep it and continue pursuing his passion for flying. He mused that he may even fly it home from Alfred after commencement.