NASA is using a converted U2 spy planes to study the icepack of the frozen northern regions of the world.
Flights are originating at Fort Wainwright, a U.S. Army base near Fairbanks, Alaska. Pilots climb to 12.5 miles above the ground to gather data. At this altitude, most light disappears from the sky, becoming darker than a moonless night. For pilots in their pressurized flight suits, the curvature of the Earth is clearly visible from twice the height of Mount Everest.
A study of the icepack of Alaska will consist of 48 hours of flight time in the once top secret aircraft. Each of the six missions will last eight hours.
Denis Steele and Tim Williams are the two pilots assigned to the NASA study. They will take turns piloting the high-flying aircraft, during the three-week-long study. When one man is in the air, the other stays on the ground, acting as a "mobile pilot." The operator on the ground works to facilitate communication between the aircraft and the ground crew, and assisting during potential in-flight problems. They also drive along runways during takeoffs and landings, assisting the pilot.
Steele and Williams use a laser altimeter, called the Multiple Altimeter Beam Experimental Lidar (MABEL) system, in order to accurately measure ice depth. This data is being collected in order to compare it to ice depths measured by the ICESat-2, scheduled for launch in 2017.
Before that mission launches, algorithms will need to be designed for the applications on-board that allow data collection and analysis. The ER-2 is one of the few powered vehicles in the world capable of producing data similar to that collected by satellites.
"All the algorithms need to be tested and in place by the time of launch. And one thing that was missing was ICESat-2-like data on the summer conditions," Thorsten Markus, ICESat-2 project scientist from the Goddard Space Flight Center, said.
The ER-2 research jet is a refashioned spy plane from the height of the Cold War - the U2. NASA owns two of the high-altitude research craft, which it received from the Air Force in 1971.
Fewer than 100 of the original spy planes were ever constructed. Designed for high-altitude reconnaissance, the first of the planes took to the air in 1957. The single-seat aircraft require a light airframe, increasing its possible maximum altitude. This leaves little room for error during flight, necessitating the role of mobile pilot.
Researchers will study melt pond coverage in the Arctic regions were melted snow pools together in low areas, as well as regions of ice largely devoid of snow. They want to know how these regions can affect warming and cooling patterns.