NASA's Hurricane and Severe Storm Sentinel (HS3) mission will be a complex one for the pilots flying NASA's Global Hawk aircraft from the ground. The mission will be the first deployment for the unmanned aircraft away from their regular base of operations at the Dryden Flight Research Center on Edwards Air Force Base, CA. In addition, the pilots will be operating the aircraft from two locations on opposite coasts.
After the upload of specialized science equipment is complete, the two Global Hawks will fly from one coast of the United States to another over sparsely populated areas and open water to reach NASA's Wallops Flight Facility in Virginia. NASA Wallops was selected as a deployment site because the Atlantic Ocean is where hurricanes begin to form. Flights from the U.S. East Coast take less transit time to the target than those from NASA Dryden and allow the aircraft to travel further out over the Atlantic and collect data for a longer period of time.
Waiting at Wallops will be a mobile ground control center, mobile payload operations center and Ku-band satellite dish – all necessary for operation of the high-altitude and long-endurance aircraft. Scientists, maintenance personnel and three pilots will support flights from Wallops.
During take off and landing of the Global Hawk, the aircraft must be in line-of-sight communications with the pilot. The pilots deployed to Wallops will manage this activity from the Global Hawk Mobile Operations Facility, handing off operation of the aircraft to Dryden after reaching an altitude of approximately 30,000 feet.
Additional pilots sitting in Dryden's Global Hawk Operations Center will receive the verbal hand-off via telephone, cross check data links with pilots at Wallops, and assume responsibility for the aircraft's operation until the mission is completed when the landing operation transfers back to Wallops. This close coordination alleviates the necessity to deploy a larger number of pilots.
When an unmanned aircraft is in the air, the ground-based pilots maintain continual contact with Federal Aviation Administration air traffic control specialists.
The pilots are in California's Mojave Desert, talking with East Coast controllers through a radio located on the aircraft. When flying in oceanic airspace, pilots talk with international controllers over telephone. This communication is vital as air traffic controllers provide the altitude and number of other aircraft sharing the same area of the U.S.'s National Airspace System and international air space as the NASA aircraft. When the Global Hawk reaches an altitude of between 60,000 and 65,000 feet, there are few aircraft competing for space.
The Global Hawk pilots will have to deal with turbulence in the hurricane flights. Fortunately, the cruise altitude is above most of the unstable air associated with that weather phenomenon. In addition, an instrument measuring turbulence was adapted and will be installed with the science payload.
