Astronauts Set Blaze as Part of Experiment : Shuttle: Foam smolders in a test designed to improve flight safety and fire prevention on Earth.
Astronauts on the space shuttle Columbia set fire to a piece of plastic foam and watched it smolder in weightlessness Friday, one day into NASA’s longest shuttle flight.
The polyurethane foam, three inches long and two inches in diameter, smoldered inside a sealed, flame-resistant chamber after Lawrence DeLucas heated it electrically. Sensors in and around the foam measured its temperature.
Safety was a must.
“A few eyebrows were raised” when researchers asked if Columbia’s seven-member crew could conduct fire experiments in orbit, said Howard Ross, chief of the microgravity combustion branch at NASA’s Lewis Research Center in Cleveland. “But when they saw our design and went through all the reviews, we comforted both the crew and the independent safety council.”
More fire experiments are scheduled with other materials, also in sealed chambers.
“We’re confident none of them is dangerous,” Ross said.
The experiments are designed to enhance flight safety and improve fire prevention on Earth.
“I hasten to add this is only a first step,” Ross said.
Astronauts have kindled fires on three other shuttle flights, using ashless filter paper. Flames travel half as fast in space as on Earth and glow a cooler blue.
Combustion scientists are especially interested in smoldering, a weak form of burning without flames, like burning cigarettes, that can develop suddenly and rapidly into a full-fledged blaze.
Researchers at UC Berkeley chose polyurethane foam for their experiment aboard Columbia because of its widespread use in seat cushions, both on the ground and in space.
The concern is not so much that smoldering foam might burst into flames aboard Columbia but rather that dangerous gases might be released, Ross said. The fire chambers have filters to trap any escaping fumes.
Nothing escaped during Friday’s test, even though more smoke was produced than expected, said principal investigator Carlos Fernandez-Pello, a professor of mechanical engineering at Berkeley.
“It was a very exciting moment,” Fernandez-Pello said.
The foam smoldered for about five minutes--25 minutes fewer than planned--before going out. Fernandez-Pello said it appears not enough heat was applied because of an equipment display problem.
Water was the big interest earlier in the day.
Astronaut Eugene Trinh set a shimmering, 3/4-inch drop of water laced with plastic tracer particles inside a module in which sound waves are used to suspend and move drops.
To researchers’ surprise, instead of sitting still the drop spun clockwise. The same thing had happened when Trinh used a small blue ball to calibrate the module.
Controlling Fire in Space
Tests aboard the shuttle will be conducted in a “glove box,” which will permit astronauts to work with fire and water in space:
35-millimeter camera
Microscope: Can be used with still or video cameras
Video cameras: Three black and white and three color heads to record experiments
Gloves: Either heavy or surgical gloves available
Video monitor
Will it Flame?
A fire requires oxygen, fuel and heat. In space, there is little air rushing in to replenish the oxygen supply to a fire. Instead of rising as it does on Earth, hot air stays low, increasing the heat. Experiments will try to determine if it will flame or merely smolder.
