Unable to afford his tuition at Kansas State, Cartwright ended his studies and worked at the University of Tulsa and the Bubble Up Bottling Company.

[1] In June 1960, Cartwright graduated from San Francisco State College with a BA Degree in Social Science.

[1] The segregated US Army assigned him to the all-African American enlisted men 349th Field Artillery Regiment at Fort Sill, Oklahoma.

[1] In November 1942, Cartwright graduated from Officers Candidate School, receiving a commission as a Field Artillery Second Lieutenant in the 599th Field Artillery Battalion of the all-African American brigade of the 92nd Infantry Division, best known as the Buffalo Soldiers[1] Serving primarily in Italy, Cartwright remained with the 599th throughout the remainder of World War II.

[4] On December 1, 1974, Cartwright and his wife Gloria were killed on TWA Flight 514 when the Boeing 727, flying in bad weather, crashed into the wooded slope of a 1,725 feet (526 m) mountain 25 nautical miles (46 km; 29 mi) northwest of Dulles International Airport.