NASA's Gulfstream III research aircraft with the JPL-developed UAVSAR synthetic aperture radar mounted under its belly is prepared for another radar-imaging mission from the Dryden Aircraft Operations Facility in Palmdale, Calif. (NASA / Tom Tschida)
› View Larger Image The long days of summer welcomed NASA's G-III environmental research aircraft when it returned to Alaska for a volcano-imaging mission Aug. 1.
Mounted in the aircraft is the Uninhabited Aerial Vehicle Synthetic Aperture Radar, or UAVSAR, developed by the Jet Propulsion Laboratory in Pasadena, Calif. The sensor detects and measures small changes in Earth's surface of geophysical interest.
En route to Alaska, the radar will image volcanoes in the Cascade Range over California, Oregon and Washington. From Elmendorf Air Force Base near Anchorage, Alaska, the G-III will fly over the Aleutian Islands while the radar images volcanoes in that area.
Differential Global Positioning System satellite information is being used in conjunction with the aircraft's precision autopilot to enable the aircraft to repeat flight lines within 15 feet of the originals flown in August 2010. The system depends on corrections received from Iridium and Inmarsat satellites. The radar's electronically steered antenna compensates for aircraft altitude and heading changes as the radar makes repeat passes over areas of interest.
NASA's Gulfstream III research aircraft with the JPL-developed UAVSAR synthetic aperture radar mounted under its belly lifts off on another environmental science mission. (NASA photo (NASA / Tom Tschida)
› View Larger Image The data collected by the UAVSAR over the West Coast and Aleutian volcanoes will be compared with similar data collected last year for signs of surface deformation that might indicate activity within a volcano.
The aircraft is scheduled to return to NASA's Dryden Aircraft Operations Facility in Palmdale, Calif., Aug. 4.