YOKOTA AIR BASE, Japan — The latest mission for retired Air Force test pilots Troy Asher and Jim Smolka doesn’t involve a need for speed, or gut-wrenching evasive maneuvers.
It’s all about precision — flying 60 miles at a time inside an imaginary “tube” 30 feet wide.
Asher was the flight commander and Smolka the co-pilot during a five-day mission to study Japanese volcanoes as part of a NASA project.
For their first mission here, the team of scientists, engineers and pilots concentrated on capturing high-resolution photographs of volcanoes that are likely to erupt, said NASA geophysicist Paul Lundgren, the principal investigator behind the study.
NASA is in the process of trying to collect as much information as possible about the “Ring of Fire” — an arc of volcanoes and fault lines encircling the Pacific Basin — to help respond to the next “Mount St. Helens-type eruption,” Lundgren said.
The ultimate goal is to use the data to help in the aftermath of a significant eruption and perhaps one day better predict when one might happen.
With its large number of active volcanoes and seismic activity, “Japan is a very important place from a geophysics point of view,” Lundgren said.
He came to Japan last month ahead of the team that recently deployed in a converted Gulfstream jet from the space agency’s Dryden Flight Reserach Center in Palmdale, Calif., — first to Elmendorf Air Force Base in Alaska, then to Yokota. The team regularly studies volcanoes along the West Coast and Hawaii and has done deployments from the North Pole to Central America.
Using a digital-imaging radar system known as UAVSAR — the only one of its kind in the world — the NASA team captured thousands of images from volcanoes all over Japan — a terabyte of data from three days of flying. Other countries, including Japan, have similar radar systems mounted on satellites in space — technology the U.S. currently does not possess.
Excluding the manpower needed for UAVSAR (Uninhabited Aerial Vehicle Synthetic Aperture Radar), the system developed by NASA’s Jet Propulsion Laboratory is worth upwards of $15 million, engineer and radar operator Tim Miller said. He and the rest of crew are technically employed by the federally funded JPL, which is managed by the California Institute of Technology for NASA.
The aircraft-mounted system is more costly to run than its equivalents in orbit but is also more flexible because of its range and ability to make repeat passes quickly, capabilities that are crucial in crisis situations, Miller said.
The sophisticated technology is classified as a potential weapons system by the International Traffic and Arms Regulations for its ability to be used for surveillance, Miller said, “but NASA guards against that.”
“We do not do surveillance,” Miller said.
The data collected during the Japan mission provides a baseline that will become useful after a return flight next year when scientists will be able to compare images from the first trip to the second. When magma accumulates, for example, typically the ground inflates.
Analyzing the net surface changes — known as deformations — will give Lundgren and other scientists clues about what’s literally boiling below the earth’s surface. By measuring that repeatedly over time, scientists can “better understand the physics of what’s happening down there, which will help inform us of future eruptions,” he said.
“(But) we don’t have enough of this data,” Lundgren said. “Every volcano is different (so) generating broad theories is tricky.”
The plane follows a straight, predetermined path, called a “science lines,” alongside a volcano or set of volcanoes. The altitude and directional coordinates of the science lines — which average about 100 kilometers — are so precise that they are likened to an invisible tube that a plane must fly inside during each run. The aircraft then loops around to photograph the volcano from the opposite side, photographing several lines during a typical five-hour mission.
“We have to fly the exact same lines to get good processing,” said science coordinator Yang Zheng, who develops the flight plans for the UAVSAR, which NASA also uses to study glaciers and other earth sciences.
After the plane nears a science line its precision autopilot system takes over, but getting close to the lines is no easy task and requires a lot of manual flying, the pilots said.
“It’s not high-speed, high-risk testing. We’re not hitting Mach 3,” Asher said. “But the science is interesting, and I’ve been all over the world in this aircraft.”
Ironically, the team left Tuesday with only a few photos — on their personal digital cameras — of Japan’s most famous volcano, Mount Fuji.
“Despite its perfect shape (Mount Fuji) is actually a volcano that has a low probability of erupting,” Lundgren said. “At least in the short term.”