In 1950, O’Toole joined the Army National Guard in Topeka, Kansas. He managed flight operations, training, and maintenance for Army aircraft, pilots, and civilian mechanics. He developed a helicopter and fixed-wing aerial surveillance program to assist in location missing persons and escaped prisoners, saving the state and city agencies countless hours of ground search time. He established procedures for assisting in state emergencies and natural disasters. Through his work with the highway Patrol, O’Toole developed the aerial system of checking vehicle speed on Interstate Highway 70 between Topeka and Fort Riley.