The University of Colorado Boulder says it has conducted the first multiple, unmanned aerial system (UAS) interception of a telltale rush of cold air preceding a thunderstorm.
Known as a ‘gust front,’ it rolled across the Pawnee National Grassland in northeast Colorado on Aug. 14, the university says, whose Research and Engineering Center for Unmanned Vehicles organized the operations, which also involved the University of Nebraska-Lincoln, Texas Tech University, Colorado State University, the University of Tübingen in Germany and the Center for Severe Weather Research in Boulder.
A gust front is a boundary that separates a cold thunderstorm downdraft from warm, humid surface air, which is of interest to scientists because it can generate damaging wind speeds up to 100 miles per hour, CU-Boulder explains.
“We believe this was the first time multiple unmanned aircraft systems were flown simultaneously to make coordinated measurements of the outflow from an evolving thunderstorm,” says Jack Elston, CU-Boulder postdoctoral fellow and also the principal investigator and organizer of the National Science Foundation-sponsored Multi-sUAS Evaluation of Techniques for Measurement of Atmospheric Properties field experiment.
As the gust front approached from the West, three teams spread out about a quarter of a mile from each other along Weld County Rd. 69 near Briggsdale and launched three small UAS, including a Datahawk and two Skywalkers – all with wingspans of less than five feet.
In addition to this event, groups from the university recently conducted several other UAS flights to take measurements for wind, temperature, pressure and humidity, as well as sample the atmosphere above different types of terrain.
Separately, the Jonathan Merage Foundation has committed to a $130,000 investment to the university’s College of Engineering and Applied Science for the procurement of a tracker vehicle and a new lightning detection instrument to be integrated into a small UAS. The system is being designed to measure electric field changes associated with lightning strikes.
This project is designed to unfold in three phases over the next year, beginning with baseline analysis and integration of the systems, followed by test flights, and finally, deployments on thunderstorms in spring 2015.