HOUSTON – Despite the ups and downs of his job, John Yaniec says he never gets bored.

The lead test director for NASA’s Reduced Gravity Program says he’s never gotten sick in more than 14,000 parabolic maneuvers conducted aboard a KC-135A, known to most as the "Vomit Comet."

"This is the best job I’ve had in 29 years," he said.

A lot of first-time passengers get airsick aboard the plane as it pulls out of a steep climb and simulates weightless conditions in space for up to 25 seconds. Researchers use the plane for experiments, while astronauts use the plane to get a brief taste of being in space.

"I don’t really keep any stats," he said. "But it amounts to a rule of thirds – one third violently ill, the next third moderately ill, and the final third not at all."

"It is out of the ordinary," he said of the brief interludes of weightlessness. "And it’s a bit of the fear of the unknown, too."

Each microgravity flight lasts two to three hours and the plane will make 30 to 40 parabolic maneuvers.

Even though he spends several hours each week on the aerial thrill ride, Yaniec shies away from more extreme forms of entertainment.

"You can ask my family," he said with a grin. "I don’t do roller coasters or amusement park rides."

As lead test director, Yaniec is responsible for ensuring the experiments carried aboard are safe and personnel flying with them are medically qualified and trained.

And wherever the plane goes, Yaniec goes with it. It flies various missions about 33 weeks per year. Recently the KC-135A flew ahead of the 747 carrying the space shuttle Columbia from Kennedy Space Center to a Boeing Co. facility in Palmdale, California.

"Every week is different around here," he said. "It’s exciting to meet different people from around the world and work with them and their experiments."

Before coming to Houston, Yaniec worked for the Air Force for 21 years. He started with NASA at the Glenn Research Center in Ohio working with a DC-9 used in a reduced gravity program and as a diver in Alabama at Marshall Space Flight Center’s Neutral Buoyancy Laboratory.

He said his favorite projects are ones involved with high school and college students -- flying their experiments aboard the KC-135A nudges them toward careers in science.

"There’s a lot of excitement and they’re doing things they normally only get to do in classrooms," Yaniec said. "When it’s career decision time, I think we have an impact."