Yvonne Brill, a pioneer in spacecraft propulsion who suspended a promising career to raise three children and then returned to work full time to achieve her greatest engineering successes, died March 27 at a hospital in Princeton, N.J. She was 88.

She had complications from breast cancer, her son Matthew Brill said.

At a time of debate over women’s prospects for both having a family and reaching the highest career levels, accounts of Mrs. Brill’s life suggest that she managed to “have it all.” She was internationally respected in her field and spoke openly about the struggles she faced in being devoted to family and work.

As a specialist in the chemistry of propulsion, she made vital contributions to the operation of the orbiting space satellites that have become essential to modern life, placing the most remote areas of the globe in virtually instantaneous communication. She held a patent for a widely used propulsion system.

She was described by a women’s engineering organization in 1945 as being possibly the only woman with a technical job who was involved in rocket propulsion.

President Barack Obama awards the National Medal of Technology to Yvonne C. Brill at the White House on Oct. 21, 2011. The award was for innovation in rocket propulsion systems for geosynchronous and low earth orbit communication satellites, which greatly improved the effectiveness of space propulsion systems. She died on March 27. (Win McNamee/Getty Images)

In 2011, President Obama awarded her the National Medal of Technology and Innovation. In 1987, when scarcely any women were members, she was elected to the National Academy of Engineering.

Mrs. Brill left full-time engineering work in the late 1950s when pregnant with her first child. She continued to do consulting work and returned to the rigors of a demanding career when she joined RCA Astro Electronics in 1966.

“I really wanted to go back to work,” she said in an interview with the Society of Women Engineers. Still, she said, it was not easy: “I felt very put upon.”

But she accepted the difficulties and lack of time for herself because “I was happy in my job, I liked what I was doing.” In addition, she said, “I felt that I was making real progress . . . introducing all these new ideas.”

Yvonne Madelaine Claeys was born Dec. 30, 1924, in a suburb of Winnipeg, in the Canadian province of Manitoba, to parents who emigrated from Belgium and who, she once recalled, probably never finished high school.

She said she “just sort of didn’t really realize that I was relatively intelligent until I got to high school and started to get top marks.”

Her father, she once said, believed that when she finished her education, she should “open up a small dress shop” or similar enterprise. But, she said, “I just wasn’t cut out for that.”

After graduating from the University of Manitoba in mathematics in 1945, she went to work for the Douglas Aircraft Co. in California and gravitated to the chemistry of propellants.

While in the Los Angeles area, she received a master’s degree in chemistry from the University of Southern California.

While at a chemistry lecture, she met her future husband, Bill Brill, who held a PhD in chemistry. Later they faced a challenge: His job opportunities were in the east, hers in the west.

Her decision to follow his career, she said, was based on her belief that “good jobs are easier to find than good husbands.” The saying became part of family lore.

The couple moved east, eventually settling near Princeton. It was in the year after her 1966 return to full-time work that she created the hydrazine resistojet, which is also known as the electrothermal hydrazine thruster.

It provides an effective way of adjusting the positions of communications and monitoring satellites to ensure proper operation. The achievement required Mrs. Brill to work many nights and weekends.

From 1981 to 1983, she worked at NASA headquarters in Washington as a manager in a solid rocket motor unit. She had also worked in London for the International Maritime Satellite Organization and was known for fostering the careers of women in technical fields.

Mrs. Brill was inducted in 2010 into the National Inventors Hall of Fame, along with the two co-
inventors of Post-it notes, prompting a Washington Post reporter to write that it required two men for the stationery item, but only one woman for the space thruster.

Her husband died in 2010 after 58 years of marriage. Survivors include three children, Matthew Brill of Swedesboro, N.J., Joseph Brill of Denver and Naomi Brill of St. Paul, Minn.; and four grandchildren.

As described by her son Matthew, Mrs. Brill’s idea for the space propulsion system was to reheat the ejected propellant before it left the nozzle. It enhanced efficiency, cut costs, reduced the payload weight and extended the useful life of the satellites.

The device was “a very simple idea,” her son said. “Mom always felt fortunate that she was lucky enough to think it up.”