Born in Ulen, Minnesota, Amundson took his first airplane ride at Minneapolis in 1936. He soon soloed and by 1941 had earned his Private license and many additional ratings. He joined the US Navy in 1944 and served as crew of an LST that took troops ashore during the invasion of Okinawa.
Following the war, Amundson worked for Valley Flying Service at Grand Forks, ND, then was hired by North Central Airlines as line mechanic, crew chief and eventually Manager of Technical Training, instructing mechanics and flight personnel. Amundson served the CAP, the Air Guard and Air Force Reserve as maintenance advisor and earned the Charles Taylor Master Mechanic Award. After his retirement from North Central, he set up his own mechanic trainings school at his home, consulting with homebuilders and restorers, and tutoring hundreds of today’s mechanics and flight technicians.