NASA - National Aeronautics and Space Administration

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The swirling circulation pattern of tropical storm Frank off the southwestern coast of Baja California was captured by Ames Research Center's HDVis camera mounted on the aft fuselage of NASA's Global Hawk unmanned research aircraft Aug. 28.
Credit: NASA/NOAA

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This graphic shows the planned flight path of NASA's Global Hawk high-altitude environmental science aircraft during its Aug. 28 flight over tropical depression Frank off the southwestern tip of Baja California.

Credit: NASA Two of NASA's environmental science aircraft were in the air this past weekend, flying hurricane-monitoring missions in connection with the aerospace agency's Genesis and Rapid Intensification Processes, or GRIP, campaign.

NASA's Global Hawk took off from NASA's Dryden Flight Research Center at Edwards Air Force Base in Southern California early Saturday morning, August 28 on an 15-hour flight that took it over Hurricane Frank in the eastern Pacific Ocean, about 250 miles off the southwestern tip of Baja California. The sensors and instruments on the remotely operated aircraft observed the storm's environment and inner structure while flying a descending "square spiral" pattern over the storm. Frank was downgraded to a tropical depression as its strength weakened over the weekend.

Meanwhile, NASA's DC-8 flying science laboratory departed Ft. Lauderdale, Fla., Monday morning, Aug. 30, on a second science flight over Hurricane Earl west of St. Croix, U.S. Virgin Islands. The converted jetliner flew an 8.5-hour science flight on Sunday, Aug. 29, over the hurricane at altitudes of 33,000 feet and 37,000 feet, and then descended to 7,000 feet northwest of the storm area to collect measurements of atmospheric aerosols.

The first DC-8 flight originated in St. Croix but diverted to land in Fort Lauderdale due to the degrading weather forecast for St. Croix associated with the approaching hurricane, whose strength had been increasing during the weekend. Mission managers have requested a flight by NASA's Global Hawk over Hurricane Earl at mid-week, with departure from Edwards tentatively slated for Wednesday evening, Sept. 1." The mission would be targeted for a duration of 24 hours.

The DC-8 and Global Hawk flights are in close support of operations being flown by NOAA aircraft that are also involved in the six-week GRIP campaign.

Alan Brown
NASA Dryden Flight Research Center