Revolving blades were a lifelong fascination for Glid Doman. He started out designing, and then manufacturing, pioneering helicopters and after that, moved on to another then-new field: air-driven turbines for generating electricity. As tireless as the blades he designed, Doman was still working well into his 90s.

Glidden Sweet Doman was born in western New York in 1921. His father and uncle set up the first electrical system for their small town, and his brother designed engines for Franklin automobiles and the first Sikorski helicopters. In his teens, Doman built motorized go-carts, and a streamlined Soapbox Derby racer, winning a regional race in Syracuse when he was 15.

After graduating from the University of Michigan, he attended a lecture by Igor Sikorsky that sparked an interest in helicopters — still a very new invention — and their rotor blades, which, back then, were suffering quickly from fatigue.

In 1943, Doman went to work for Sikorsky in Bridgeport, specializing in making blades strong, long-lasting, yet light and flexible. It was during World War II, and his contributions were so vital that Igor Sikorsky himself appealed to the draft board to keep him on the test program.

In 1945, he left Sikorski to found Doman Helicopters Inc., producing small helicopters and headquartered for many years at Danbury Airport. There he developed innovations years earlier than larger competitors; some of them are now standard in today’s helicopter technology.

“The driving force behind Doman engineering was sharp focus on understanding what the helicopter and especially its blades and rotor hub were doing,” said Susan Orred in a 2013 profile of Doman. “The resulting insights produced the firm’s hallmark trait - aeronautic design with elegant simplicity.”

In the 1950s, the company produced three LZ-5 helicopters, which employed his rotor designs and other innovations. They could carry six passengers plus a pilot and copilot, and received both military and commercial certification.

He hoped to gain military contracts, and two LZ-5s were sold to the Army. However, the military never bought any more. Lack of government contracts spelled doom for the company, which had as many as 130 employees. It moved to Pennsylvania in 1965 and closed in 1969, The only remaining LZ-5 is at the New England Air Museum at Bradley Airport in Windsor Locks, along with a smaller Doman R-6 helicopter.

Doman spent several years with Boeing, designing rotors for giant heavy-lift helicopters. He then turned to a new career as chief systems engineer of the wind energy program at Hamilton Standard, developing huge wind turbines, which share some blade technology with helicopters. In 2003, he formed Gamma Ventures Inc. to market production rights for the turbines he helped design in Italy.

Doman had lived in Ridgefield from 1958 to 1967 — his wife, Joan, who died in 2003, was a teacher at RHS. He spent his last 35 years in Granby, active into his 90s. He died in 2016 at 95.

—Jack Sanders