in cold weather search and rescues. He was also directly responsible for persuading the U.S. Air Force to purchase the de Havilland Canada DHC-2 Beaver bush aircraft, one that became an important search and rescue aircraft for the Arctic. On 23 May 1949, while commanding the 10th Rescue Squadron, Balchen flew a Douglas C-54 Skymaster from Fairbanks, Alaska, via the North Pole to Thule Air Base, Greenland. Balchen was primarily responsible for the pioneering and development of the strategic air base at Thule, Greenland, built secretly on his recommendation, in 1951 under severe weather conditions which, by extending the range of the Strategic Air Command, increased the capabilities that made the SAC a significant deterrent to Soviet aggression during the Cold War. Post-retirement After retiring from the U.S. Air Force in 1956, Colonel Balchen continued to serve the Air Force on special assignments and aviation and energy industries as a consultant. He joined General Precision Laboratories as a consultant in 1959, as well as working with a host of other companies including Hughes Aircraft, General Dynamics, Canadair and the Electric Boat Company. Working for Canadair in 1966, then the parent company, General Dynamics, from 1966 to 1971, Balchen had authority over projects as diverse as ice-breakers, tankers, new epoxy materials for submarine construction, seagoing electronic weather systems and over-snow vehicles. In 1962, he also worked with the USAF presenting a proposal on the Apogee Intercept Defense System (AIDS) in 1962 and later, was the leading advocate for "Project Iceman", a proposed system of intermediate range ballistic missiles (IRBMs) stationed in Greenland. Colonel Balchen was among 27 passengers on board the first circumnavigation of the Earth over both poles. The aircraft was a brand-new, chartered Flying Tiger Line Boeing 707-349C jet with U.S. registration N322F, which had been modified with additional fuel tanks installed in the front passenger cabin. The route taken, between 14 and 17 November 1965, was from Honolulu, over the North Pole, to London; Lisbon; Buenos Aires; before flying over the South Pole and continuing on to the last refueling stop at Christchurch before returning to Honolulu. Balchen was the only passenger allowed into the cockpit when the four pilots, who were all qualified Boeing 707 captains, performed four 360-degree loops over the South Geographic Pole. As well as being the first such flight, this would remain the fastest until succeeded by Pan Am Flight 50, a Boeing