Photo by: The News-Gazette

Lee H. Sentman III, a professor emeritus from the University of Illinois, died in a mid-air collision in Florida.

A University of Illinois professor emeritus has died in a Florida plane crash, flying an experimental plane he loved.

Lee H. Sentman III, 73, who taught for 35 years at the UI, died Saturday when his experimental plane collided with another small plane about 4 miles south of Williston, Fla.

Two people aboard the other plane also were killed, the Levy County sheriff's office told The Associated Press. Their names have not yet been released.

Mr. Sentman was flying an RV-6 experimental aircraft at a gathering of experimental plane enthusiasts. He was a professor emeritus with the University of Illinois who lived in Dewey before moving to Florida.

A colleague, physics Professor Munir H. Nayfeh, said Professor Sentman was an innovator in aeronautics and lasers as well as in his hobby, experimental planes.

According to Professor Sentman's biography, he graduated from the UI with a bachelor's degree in aeronautical engineering in 1958. He then earned a doctorate in aeronautics and astronautics from Stanford University in 1965.

The UI Web site listed him as director of the Chemical Laser Laboratory with the department of aeronautical and astronautical engineering at the university.

Mr. Sentman and his father, Lee Sentman Jr., were believed to be the only father-son combination to win a UI award for athletics and scholarship. His father set a hurdles record in track; the younger man was on the fencing team.

According to Capt. Evan Sullivan of the Levy County sheriff's office, Williston resident Debbie Phillips called his office after hearing "what she thought was a gunshot. But when she looked out her window, she discovered a plane had crashed in the field behind her house."

Officers found an experimental small airplane upside down about 300 yards from the residence.

"Upon further investigation, a second airplane, a Piper 32, was discovered fully engulfed in flames approximately 400 yards to the west of the experimental plane. The Williston Fire Department extinguished the fire with water and foam and discovered two unidentified bodies in the second airplane crash," the sheriff's office said in a report.

The Levy County sheriff's office told The Associated Press that a husband and wife believed to have been in the Piper had parked their car at the airport and did not return. Investigators say the German consulate is helping to locate the couple's relatives in that country.

Preliminary investigation reveals that the experimental airplane left the Ocala Airport and the Piper 32 left the Williston Airport. The two had a mid-air collision around 11:45 a.m., the report said.

Nayfeh called the news "tragic." He said Professor Sentman was a mentor to him.

"I first met Lee in 1980 right after I arrived at the UI. He contacted me to welcome me and asked me to bring in my laser physics expertise to his aero and astro expertise to write a proposal to carry research in high-power lasers," Nayfeh said.

Like his mentor, Nayfeh had graduated from Stanford.

"He knew my brother Ali Nayfeh who was his classmate at Stanford. I soon discovered that, though laser physics was not his expertise, he is a wiz in design, construction and management. In no time he became a world-class expert in high-power lasers. We conducted joint research on design, construction and operation of high power chemical lasers in the '80s," Nayfeh said

Nayfeh said he and Professor Sentman also shared bad moments.

"We shared a similar tragic death of one of our graduate students, Ken Harrick, who worked with us on the chemical laser project, in a crash of a C-130 in the early '80s," he said.

Harrick had worked part time in the Air National Guard.

"This was devastating for both of us, as just one week earlier Ken survived a very deadly hydrogen explosion in our joint lab in Loomis Laboratory of Physics. Lee has always reminded Ken of the danger of flying aircraft, especially the C-130. One day, we went upbeat to his house to congratulate him and his wife for his survival; only a week later we found ourselves going back to give condolences to his wife," Nayfeh said.