Weather balloon

NASA turns Saab 340s into flying wx stations
January 31, 2007 - 5:35am

NASA researchers are seeking to bring better weather information to pilots and controllers by converting a fleet of regional turboprop airliners for service as flying weather reporting stations.
NASA Turns Regional Airline Turboprops into Flying Weather Stations
September 18, 2006 - 11:52am
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Notwithstanding this spring’s violent (and numerous) tornadoes, forecasters in the Midwest are able to make more accurate local weather predictions thanks to an airborne sensor being tested by NASA’s aviation safety program.