Bobbie A. Brassfield, 44, an Army lieutenant colonel who retired for reasons of health last May after 21 years of service, died of cancer Thursday at Walter Reed Army Medical Center.

Col. Brassfield, an Army aviator, had maintained a home in Springfield, Va., since 1966, when he was assigned to the Federal Aviation Administration to work on research and development projects. He also was stationed here with the Defense Intelligence Agency.

He was born in Stigler, Okla., and grew up in Wasco, Calif. He attended California State Polytechnic College and was commissioned in the Army in 1957.

In addition to his assignments here, he served two tours of duty in Vietnam and one in Germany. He was a graduate of the Command and General Staff College at Fort Leavenworth, Kan., and earned a bachelor's degree at Benedictine College in Atchison, Ken. While stationed in Culver City, Calif., he earned a master's degree in business administration from Pepperdine University.

Col. Brassfield's military decorations included the Distinguished Flying Cross and the Air Medal with Oak Leaf Clusters.

Survivors include his wife, Virginia, of the home in Springfield; three daughters, Judith, Susan and Karen, all of the home; his mother, Bertha Olivarez, of Wasco; a sister, Phyllis Posey, also of Wasco; a brother, Troy H., of Battle Creek, Mich., and a half-brother Billy Kilgore, of Los Angeles.