Colonel Crumly, a native of  Alabama graduated from the Georgia Institute of Technology in electrical engineering as an honors graduate in mid 1939, just as the war in Europe was beginning. Upon graduation he was commissioned as a Second Lieutenant in the Organized Reserve Corps and after a short time in the Alabama National Guard he was transferred to the U.S. Army Signal Corps, where he helped organize the 23rd Signal Troop, later becoming part of the Coast Artillery Corps.

His battalion was called for active duty in World War II in February 1941. His engineering background, training in radar at the Fort Month Signal School,  and experience in radar controlled searchlights for fighter intercept in the Coast Artillery led to rapid promotions to become the youngest Major in the U.S. Army Signal Corps at the age of 25 by late 1942. During the next year Major Crumly became the Director of the Airborne Division of the Southern Signal School at Camp Murphy Florida after serving on the staff at Fort Monmouth that established the Camp Murphy Signal School  and officer in-charge of the Gun-Laying Equipment Division and the Advanced Radio Division.

Major Crumly was relieved as Director of the Southern School and assigned to Headquarters Allied Expeditionary Forces in Europe March 1944. because radar was being used for the first time in war and there were few knowledgeable, he was selected to be the senior American Staff officer for all Radar matters on General Eisenhower’s Staff upon the establishment of SHAEF, (Supreme Headquarters Allied Expeditionary Forces). His experience in both technical and operational details in the operational planning for radar employment in Operation "Over Lord", the Normandy 
Invasion, led to his return temporarily to Washington to advise on characteristics which should be provided in on-going radar development.

Lieutenant Colonel Crumly returned to Europe and soon was awarded the Bronze Star with two Oak Leaf Clusters on 20 March 1945 for meritorious service in operational activities against the enemy, providing direct front-line support to units engaged in radar controlled blind bombing operations in the final phase of the Battle of the Bulge.

After the war, Lieutenant Colonel Crumly was assigned to an Air Force Board, organized to evaluate and determine the best operational and technical concepts used during the war. On 26 March 1946, Lieutenant Colonel Crumly was awarded a Medal and Certificate of Decision from the Republic of France, la Croix de Guerre avec Etole de Vermeil (with the red star) for services exceptional de Guerre during operations assisting the French on radar systems in North Africa during the liberation of France.

After transferring to the newly created Air Force, he was placed in charge of evaluating all new electronic equipment for the Air Force, followed by assignment as Chief, Proof Test Division, responsible for operational testing of aircraft, missiles, ordnance, communications and navigation equipmment. He headed a special detail which planned and surveyed the radar network for the Alaskan Air Defense system, and was immediately thereafter assigned to the Armed Forces Special Weapons Project as the Deputy Director of Training for Atomic Weapons at Sandia Base, New Mexico.

After commanding the Development Division, Air Force Armament Center, a critical assignment in the Ballistic Missiles Division, and Commander of the Gulf Missile Test Range, Colonel Crumly completed his career in the Missile Command in the Pentagon and retired from active duty with 26 years of distinguished service in 1965.

Upon retiring from the Air Force, he was employed in 1966 by the Bendix Corp in Detroit and served as Long Range Planning Director until retiring in 1975. He then returned to the Washington area and worked in the late 1970s for Government Institutes Inc. in Rockville as Exposition Manager of the Annual Energy Technology Conference.

Colonel Crumly was a prize-winning photographer and member of the Latent Image Workshop.

A sailor, he had served as commodore of the Annapolis Naval Sailing Association.