Lieutenant Colonel Fellbaum commanded the 7th Transportation Motor Pool, U.S. Army. He developed Laennec's cirrhosis of the liver with bleeding esophageal varius and was evacuated to the 21st Station Hospital, Pusan, South Korea, where he died on 7 January 1954.

Fellbaum was awarded the Korean Service Medal, the United Nations Service Medal, the National Defense Service Medal, the Korean Presidential Unit Citation and the Republic of Korea War Service Medal.