FAIRBANKS -- A civilian version of the U-2 jet began reconnaissance flights across Alaska and the Arctic Ocean this week, collecting data for NASA research aimed at learning more about the effects of melting ice on sea level.
With a 103-foot wingspan, the single-engine ER-2 performs like a jet-powered glider with a crew of one. Pilot Tim Williams took off from Fort Wainwright shortly before noon Thursday, turned north and quickly climbed to 60,000 feet for an eight-hour flight straight to the North Pole and back.
Assisting Williams from Fort Wainwright, pilot Denis Steele served as an on-the-ground adviser, helping Williams on takeoff and staying in touch throughout the flight by satellite phone. The two take turns flying the aircraft and assisting from the ground.
Williams flew to the North Pole along the 150th meridian and back along the 140th meridian, while Steele tracked his progress on a laptop. Because of the conditions at the edge of the stratosphere, the ER-2 pilot wears a pressure suit during the flight.
When the ER-2 returns for a landing, the mobile pilot on the ground goes out on the airfield to assist, following the plane down the runway in a chase car at speeds of close to 100 mph.
“The mobile is on the ground to help the pilot run checklists because when you’re flying in a pressure suit, typically your hands are full,” said Steele, who flew the aircraft Wednesday on a seven-hour excursion that covered much of Southcentral and Southeast Alaska, passing over volcanoes, glaciers and ice fields.
The pilot in the chase car also advises the pilot in the aircraft when he is just a few feet above the ground. Steele said the goal is to get the aircraft about 6 inches off the ground until the speed drops enough to land, which is close to a stall speed.
“On the ground in windy conditions it’s helpful to have a chase car behind the aircraft because you like to have the main and the tail wheel touch at the same time, if not the tail wheel slightly first, because that’s how you control the aircraft,” he said.
“You lose ground reference as you start to stall, if you will. When you do that the plane has a tendency to rock a little bit.”
The pilot in the chase car is there to help give the pilot in the aircraft instructions on rudder settings and wing height and help with safety in any way he can, said Steele, a retired Air Force major.
“The biggest thing is trying to land straight, keeping the tail wheel and the main gear in line as you’re slowing down,” he said. “Once it’s on the ground the pilot pops the speed brakes.”
He said the plane could easily start flying again after it lands if there is an unexpected gust.
“It’s a jet-powered glider,” he said.
Williams and Steele plan to take more flights over the next couple of weeks, working with scientists on the ground to gather information about ice, water and forests.
The ER-2 is scheduled for up to 48 flight hours by the end of July for missions on which NASA equipment will record conditions on sea ice and land with lasers and photo detectors.
The NASA team of scientists, engineers and pilots is here to operate the Multiple Altimeter Beam Experimental Lidar, or MABEL, which is designed to gather key data for use in enhancing remote sensing work on sea ice.
Once the pilot reaches 60,000 feet he activates the automated equipment that measures elevation and ice conditions by directing a laser toward the ground and measuring changes in the return signal.
Kelly Brunt, a NASA glaciologist, said they are trying to develop computer programs that will be of use for a 2017 satellite mission. She said the equipment has to be able to deal with winter ice and the water conditions of the summer.
About half of the group deals with the aircraft and half deals with the scientific aspects of the research, operating out of a hangar on Fort Wainwright.
The MABEL equipment on the ER-2 is to look at a variety of ice and water conditions on land and on the ocean over the next couple of weeks.
The primary goal of the future satellite mission is to determine how the polar ice caps are responding to climate changes and how land ice contributes to changes in sea level.
She said in 2012, an April mission to Iceland produced good information and insights about winter ice measurements.
“Now we want to see what the summer ice looks like in our laser signal, what water looks like on the surface of ice in our laser return.”
Steele flew over Southcentral and Southeast Alaska on Wednesday, covering Bagley Ice Field and the Juneau Ice Field, as well as recording data from the Columbia glaciers and the Nabesna and Kennicott glaciers in the Wrangell Mountains.
Skies were clear enough to record data on about half of the lidar targets.
The scientists hope to use the data gathered on these flights to create computer programs that allow the equipment to deal with ice and water when making elevation studies.
“We’re trying to see if there’s any penetration of the signal in the melt ponds or if it just bounces off the surface,” she said.
They want to measure ice but realize that water complicates the effort and has to be factored into the analysis.