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NASA will set prescribed fires in space
Scientists hope to learn how fires on a spacecraft burn without gravity or convection.
Like a fire onboard a ship, a fire on a spacecraft is a nightmare scenario with possibly disastrous consequences. NASA is doing what it can to prevent fires in space. The agency has conducted small-scale studies on the International Space Station (ISS) to determine how fires spread in microgravity without convection. This also helps them figure out the best way to suppress a fire after it starts.
One way to study the problem is to conduct prescribed fires, which is exactly what they will do. The project is called Spacecraft Fire Experiment, or Saffire. Over the next year or so they will set fires on three Cygnus spacecraft used for ferrying supplies to the ISS.
After the unmanned Cygnus offloads its cargo it will detach from the ISS and eventually burn up as it re-enters Earth’s atmosphere. But before being destroyed by fire over the Pacific Ocean scientists will use the vehicle as an experiment bed.
The launch of the first Cygnus spacecraft with the Saffire I experiment is scheduled for March 22.
The video below elaborates on this experiment.
An excerpt from a NASA article:
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…“A spacecraft fire is one of the greatest crew safety concerns for NASA and the international space exploration community,” says Gary Ruff, Saffire project manager.
Saffire will involve far larger flames than previous experiments and will investigate the way fire spreads on a variety of combustible materials. Because the experiments will be conducted away from the space station, there is no risk to the astronauts aboard.
Each Saffire experiment will be remotely operated inside a 3 x 5 foot module, split into two compartments. One side of the module is an avionics bay that contains sensors, high definition video cameras and signal processing equipment. The other side contains the hardware required to ignite a large flame and burn the fabrics and materials inside.
When the experiments begin, Saffire I and III will burn one large 16 by 37-inch piece of SIBAL cloth, which is a blend of fiberglass and cotton. This material has been studied in previous microgravity combustion experiments, although at a much smaller size. The SIBAL cloth will be burned from the bottom to see how the flame spreads. If the flame extinguishes itself, scientists will light it at the top and see what happens as the flame moves opposite to the airflow.
Saffire II, scheduled to launch in June from Wallops Flight Facility in Virginia, will ignite a mix of nine different samples of materials used routinely on the space station including flame retardant fabrics used for astronaut clothing, station Plexiglas window samples with edge variations and structures used for storage containers and silicone composites. Each sample is two by 11 inches, the size sample NASA uses to screen materials on Earth before they are used on a spacecraft.
“Saffire seeks to answer two questions,” says David Urban, principle investigator. “Will an upward spreading flame continue to grow or will microgravity limit the size? Secondly, what fabrics and materials will catch fire and how will they burn?”…
Red Flag Warnings for five states in the central U.S.
The National Weather Service has issued Red Flag Warnings for areas in Nebraska, Colorado, Kansas, Illinois, and Missouri. The culprit is the forecast for strong winds and low humidity.
Be sure and vote in the poll to let us know which fire weather map you prefer.
The map was current as of 9:30 a.m. MDT on Wednesday. Red Flag Warnings can change throughout the day as the National Weather Service offices around the country update and revise their forecasts and maps. For the most current data visit this NWS site.
Reducing firefighter risk before the fire
Today the National Interagency Fire Center released a seven-minute video titled Reducing Firefighter Risk Before There is Smoke in the Air. It covers fuel management, fire prevention, community partnership, and public education.
There is no description or indication that it is designed to be part of the 2016 annual wildland firefighter refresher curriculum.
Winter weather — precursor to the 2016 wildfire season
Above: precipitation last 90 days, percent departure from normal. Click to see larger version.
There are three main factors that influence the behavior of a wildland fire: weather, fuel, and topography. Thankfully topography does not change from year to year in any significant manner. If it did, the job of wildland firefighters would be incredibly more difficult. Weather and fuels (vegetation) do change, not only from year to year from but from day to day — even hour to hour as the fine fuels absorb moisture out of the air. The weather is infinitely variable and has a huge effect on fires and fuels. This turns many firefighters into amateur meteorologists in an effort to master their craft and keep themselves and their colleagues safe.
Often at this time of the year as preparations are under way for the western wildfire season we look back at the winter weather.
There is little doubt that precipitation and temperature over the last 90 days will have an effect on summer fires. Many media outlets find it hard to resist the temptation on a slow news day to exaggerate how, for example, a dry winter might lead to disastrous wildfires. But the fact is summer weather has a greater effect on the number of acres burned than the conditions six months before. Hot, dry, and windy conditions in the summer are usually associated with a busy fire season.
Precipitation
As you can see in the map above, large sections of the forested areas in the northwest had above normal precipitation over the last 90 days. There are regions in Montana, Washington, and Oregon that had 150 to 200 percent of average. However, much of the southwest, southern California, and areas within the states of Colorado, Utah, Nevada, and Wyoming were below normal.
Heavy rain this winter in northern California, 110 to 150 percent of normal, has been adding a lot of water to the reservoirs that have been in pretty bad shape for the last couple of years. The two largest reservoirs in the state, Lake Shasta and Lake Oroville, have both refilled to levels above the historical average and are 81 and 73 percent full. Most of the lakes farther south have some serious catching up to do.
Snow Cover
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Chance for dry thunderstorms in Kansas and Nebraska
The National Weather Service has issued Red Flag Warnings or Fire Weather Watches for areas in Nebraska, Kansas, Colorado, Oklahoma, New Mexico, and Texas.
The Storm Prediction Center’s forecast (see map below) includes a chance of isolated dry thunderstorms with enhanced outflow winds in northeast Kansas and southeast Nebraska.
If you have not yet, vote in the poll to let us know which fire weather map you prefer.
The maps were current as of 11:30 a.m. MDT on Tuesday. Red Flag Warnings can change throughout the day as the National Weather Service offices around the country update and revise their forecasts and maps. For the most current data visit this NWS site.
