Image Caption: The NASA Global Hawk 872 lands at 7:43 a.m. EDT, August 27, at the Wallops Flight Facility in Virginia following a 22-hour transit flight from its home base at the Armstrong Flight Research Center in California. Credit: NASA/ Brea Reeves

Rob Gutro, NASAs Goddard Space Flight Center

The first of two unmanned Global Hawk aircraft landed at NASAs Wallops Flight Facility in Wallops Island, Virginia, on Aug. 27 after surveying Hurricane Cristobal for the first science flight of NASAs latest hurricane airborne mission.

NASAs airborne Hurricane and Severe Storm Sentinel, or HS3, mission returns to NASA Wallops for the third year to investigate the processes that underlie hurricane formation and intensity change in the Atlantic Ocean basin. HS3 is a collaborative effort that brings together several NASA centers with federal and university partners.

The two unmanned Global Hawks participating in HS3 are based at NASAs Armstrong Flight Research Center at Edwards Air Base, California, but will be temporarily housed at NASA Wallops for the duration of the HS3 mission which runs through Sept. 29. That window for the mission coincides with the peak of the Atlantic hurricane season that runs from June 1 to Nov. 30.

NASA Global Hawk 872 departed NASA Armstrong on the morning of Aug. 26 and arrived at NASA Wallops at 7:43 a.m. EDT on Aug. 27. Global Hawk number 871 is scheduled to fly to Wallops within a week.

Tropical Storm Cristobal became a hurricane late on August 25 as it was moving through the Bahamas. During the Global Hawks 22 hour mission it flew a lawnmower or back and forth pattern over Hurricane Cristobal while gathering data using dropsondes and two other instruments. There were 83 dropsondes loaded in the aircraft, with two of them were dropped over the Gulf of Mexico and the other 81 dropsondes dropped over Cristobal. A dropsonde is a device that measures winds, temperature, pressure and humidity as it falls from the aircraft to the surface.

The instruments are tested and then integrated onto each Global Hawk at Armstrong, said Marilyn Vasques, HS3 Project Manager of NASA Ames. Before the cross-country flights, the ground operations center at Wallops tested the various instruments aboard both aircraft while they were still at Armstrong. After integration and outdoor tests we conduct a Combined Systems Test on the ground as well as a test flight near Armstrong before the instruments and aircraft are ready to transit explained Vasques. Checking the performance of the instruments over that long distance while they were at a NASA center was critical to ensure they would operate correctly while in-flight over Atlantic hurricanes.

Now that the first Global Hawk is at Wallops, the mission will investigate any significant disturbances that might develop in the western Atlantic. The HS3 mission will investigate disturbances before they become depressions to examine how a storm forms. The mission is also looking for conditions that favor (or promote) rapid intensification of tropical cyclones.

Twice a day we hold weather briefings looking for storms or disturbances that could become storms, said Scott Braun, HS3 Principal Investigator from NASAs Goddard Space Flight Center in Greenbelt, Maryland, working at Wallops during the mission. We evaluate the targets in terms of our science objectives and determine which one best addresses those objectives. We factor in stage of the life cycle of the storm, likelihood of formation or intensification, interaction with the Saharan Air Layer, among other things.

Excerpt from:

NASA Begins Hurricane Mission with Global Hawk Flight To Cristobal