Engineering a smooth landing on the Greenland ice cap

Published Sept. 22, 2017
Engineering a smooth landing on the Greenland ice cap

A snow-equipped tractor, with attached grooming rig and skis designed by the U.S. Army Cold Regions Research and Engineer Laboratory, smooths the skiway at Summit Station, Greenland.

Summit Station, located at the peak of the Greenland ice cap at an elevation of 3200 meters (10,500 feet) above sea level, is a scientific research station established by the National Science Foundation. Polar engineering expertise at the U.S. Army Cold Regions Research and Engineering Laboratory in Hanover, New Hampshire has been vital to improved safety and efficiency of aircraft operations at the site.

Summit Station maintains a 5120-m long (16,800 feet) skiway on compacted snow over the glacial ice. Transportation to the station is mostly accomplished by skied airplanes, currently Twin Otters and LC-130s, operated by the Air National Guard’s 109th Airlift Wing. From mid-April through August each summer, the skiway regularly sees three to four LC-130 flights per month.

CRREL research engineer T. J. Melendy evaluated the skiway’s construction and maintenance, and the heavy equipment needed to improve the safety and efficiency of takeoffs and landings.  He measured the skiway’s surface strength and snow density during its summer flight operations, and trained the skiway’s operators in the procedures needed to keep the skiway strong, smooth, and level.  

“We improved the designs of multiple pieces of equipment used on the skiway. We designed the ski used on the tractor rig and modified the sheepsfoot roller that compacts the skiway. We even built the unique rammsonde, a device used to test the strength of the compacted snow,” said Melendy. 

CRREL developed the procedures that keep the skiway in optimal condition, which reduces the number of attempts at takeoff, fuel consumption, and the need for Jet-Assisted Take-Offs. Maintaining the skiway’s strength also maintains a higher allowable cargo load, thereby reducing the number of costly flights required and their resulting emissions.  
Improving the Summit Station skiway is key step in ensuring the safety of the 109th Airlift Wing flight personnel and the scientists traveling to and from the station, reducing cost and preserving the station’s clean-air environment in support of ongoing polar research.