William Sterling Parsons
William Sterling "Deak" Parsons was an American naval officer who worked as an ordnance expert on the Manhattan Project during World War II. He is best known for being the weaponeer on the Enola Gay, the aircraft which dropped an atomic bomb on Hiroshima, Japan, in 1945. To avoid the possibility of a nuclear explosion if the aircraft crashed and burned on takeoff, he decided to arm the bomb in flight. While the aircraft was en route to Hiroshima, Parsons climbed into the cramped and dark bomb bay, and inserted the powder charge and detonator. He was awarded the Silver Star for his part in the mission.
A 1922 graduate of the United States Naval Academy, Parsons served on a variety of warships beginning with the battleship. He was trained in ordnance and studied ballistics under L. T. E. Thompson at the Naval Proving Ground in Dahlgren, Virginia. In July 1933, Parsons became liaison officer between the Bureau of Ordnance and the Naval Research Laboratory. He became interested in radar and was one of the first to recognize its potential to locate ships and aircraft, and perhaps even track shells in flight. In September 1940, Parsons and Merle Tuve of the National Defense Research Committee began work on the development of the proximity fuze, an invention that was provided to the US by the UK Tizard Mission, a radar-triggered fuze that would explode a shell in the proximity of the target. The fuze, eventually known as the VT fuze, Mark 32, went into production in 1942. Parsons was on hand to watch the cruiser shoot down the first enemy aircraft with a VT fuze in the Solomon Islands in January 1943.
In June 1943, Parsons joined the Manhattan Project as Associate Director at the Project Y research laboratory at Los Alamos, New Mexico, under J. Robert Oppenheimer. Parsons became responsible for the ordnance aspects of the project, including the design and testing of the non-nuclear components of nuclear weapons. In a reorganization in 1944, he lost responsibility for the implosion-type fission weapon, but retained that for the design and development of the gun-type fission weapon, which eventually became Little Boy. He was also responsible for the delivery program, codenamed Project Alberta. He watched the Trinity nuclear test from a B-29.
After the war, Parsons was promoted to the rank of rear admiral without ever having commanded a ship. He participated in Operation Crossroads, the nuclear weapon tests at Bikini Atoll in 1946, and later the Operation Sandstone tests at Enewetak Atoll in 1948. In 1947, he became deputy commander of the Armed Forces Special Weapons Project. He died of a heart attack in 1953.
Early life
William Sterling Parsons was born in Chicago, Illinois, on 26 November 1901, the oldest of three children of a lawyer, Harry Robert Parsons, and his wife Clara, née Doolittle. Clara was the granddaughter of James Rood Doolittle, who served as US Senator from Wisconsin between 1857 and 1869, and of Joel Aldrich Matteson, Governor of Illinois from 1853 to 1857.In 1909, the family moved to Fort Sumner, New Mexico, where William learned to speak fluent Spanish. He attended the local schools in Fort Sumner and was home schooled by his mother for a time. He commenced at Santa Rosa High School, where his mother taught English and Spanish, rapidly advancing through three years in just one. In 1917 he attended Fort Sumner High School, from which he graduated in 1918.
In 1917 Parsons traveled to Roswell, New Mexico, to take the United States Naval Academy exam for one of the appointments by Senator Andrieus A. Jones. He was only an alternate, but passed the exam while more favored candidates did not, and received the appointment. As he was only 16, two years younger than most candidates, he was shorter and lighter than the physical standards called for, but managed to convince the examining board to admit him anyway. He entered the Naval Academy at Annapolis, Maryland, in 1918, and eventually graduated 48th out of 539 in the class of 1922, in which Hyman G. Rickover graduated 107th. At the time, it was customary for midshipmen to acquire nicknames, and Parsons was called "Deacon", a play on his last name. This became shortened to "Deak".
Ordnance
On graduating in June 1922, Parsons was commissioned as an ensign and posted to the battleship, where he was placed in charge of one of the 14-inch gun turrets. In May 1927, Parsons, now a lieutenant, returned to Annapolis, where he commenced a course in ordnance at the Naval Postgraduate School. He became friends with Lieutenant Jack Crenshaw, a fellow officer attending the same training course. Jack asked Parsons to be best man at his wedding to Betty Cluverius, the daughter of the commandant of the Norfolk Navy Yard, Rear Admiral Wat Tyler Cluverius Jr., at the Norfolk Navy Chapel. As best man, Parsons was paired with Betty's maid of honor, her sister Martha. Parsons and Martha got along well, and in November 1929, they too were married at the Norfolk Navy Chapel. This time, Jack and Betty Crenshaw were best man and maid of honor.File:Naval Research Laboratory-Washington.jpg|left|thumb|Naval Research Laboratory complex on the Potomac River in Washington, DC
The ordnance course was normally followed by a relevant field posting, so Parsons was sent to the Naval Proving Ground in Dahlgren, Virginia, to further study ballistics under L. T. E. Thompson. Following the usual pattern of alternating duty afloat and ashore, Parsons was posted to the battleship in June 1930, with the rank of lieutenant. In November, the commander in chief United States Fleet, Admiral Jehu V. Chase, hoisted his flag on the Texas, bringing Cluverius with him as his chief of staff. This was awkward for Parsons, his son-in-law, but Cluverius understood, being himself the son-in-law of an admiral, in his case, Admiral William T. Sampson.
In July 1933, Parsons became liaison officer between the Bureau of Ordnance and the Naval Research Laboratory in Washington, D.C. At the NRL he was briefed by the head of its Radio Division, A. Hoyt Taylor, who told him about experiments that had been carried out into what the Navy would later name radar. Parsons immediately recognized the potential of the new invention to locate ships and aircraft, and perhaps even track shells in flight. For this, he realized that he was going to need high frequency microwaves. He discovered that no one had attempted this. The scientists had not considered all the applications of the technology, and the Navy bureaus had not grasped their potential. He was able to persuade the scientists to establish a group to investigate microwave radar, but without official sanction it had low priority. Parsons submitted a memorandum on the subject to the Bureau of Ordnance requesting $5,000 per annum for research. To his dismay, the BuOrd and Bureau of Engineering, which was responsible for the NRL, turned down his proposal.
Some thought that Parsons was ruining his career with his advocacy of radar, but he acquired one powerful backer. The Chief of the Bureau of Aeronautics, Rear Admiral Ernest J. King, supported the use of radar as a means of determining aircraft altitude. When the Bureau of Engineering protested that such a device would necessarily be too large to carry on a plane, King told them that it would still be worthwhile, even if the only aircraft in the Navy big enough to carry it was the airship.
Parsons's marriage produced three daughters. The first, Hannah, was born in 1932; the second, Margaret, followed in 1934. Hannah died of polio in April 1935. Parsons returned to sea in June 1936 as the executive officer of the destroyer. He was promoted to lieutenant commander in May 1937. His third daughter, Clara, was born the same year. On that occasion, Parsons left Martha with the newborn and three-year-old Peggy to care for and reported for duty the next day, believing that his first responsibility was to his ship. His skipper, Commander Earl E. Stone, did not agree, and sent him home. In March 1938, Rear Admiral William R. Sexton had Parsons assigned to his flagship, the cruiser, as gunnery officer. Parsons's task was to improve the gunnery scores of his command, and in this he succeeded.
Proximity fuze
Parsons was posted back to Dahlgren in September 1939 as experimental officer. The atmosphere had changed considerably. In June 1940, President Franklin D. Roosevelt approved the creation of the National Defense Research Committee, under the direction of Vannevar Bush. Richard C. Tolman, dean of the graduate school at Caltech, was given responsibility for the NDRC's Armor and Ordnance Division. Tolman met with Parsons and Thompson in July 1940, and discussed their needs. Within the Navy, too, there was a change of attitude, with Captain William H. P. Blandy as the head of BuOrd's Research Desk. Blandy welcomed the assistance of NDRC scientists in improving and developing weapons.In September 1940, Parsons and Merle Tuve of NDRC began work on a new concept. Shooting down an aircraft with an anti-aircraft gun was a difficult proposition. As a shell had to hit a speeding aircraft at an uncertain altitude, the only hope seemed to be to fill the sky with ammunition. A direct hit was not actually required; an aircraft might be destroyed or critically damaged by a shell detonating nearby. With this in mind, anti-aircraft gunners used time fuzes to increase the possibility of damage. The question then arose as to whether radar could be used to create an explosion in the proximity of an aircraft. Tuve's first suggestion was to have an aircraft drop a radar-controlled bomb on a bomber formation. Parsons saw that while this was technically feasible, it was tactically problematic.
The ideal solution was a proximity fuze inside an artillery shell as was first conceived by W. A. S. Butement, Edward S. Shire, and Amherst F. H. Thomson, researchers at the British Telecommunications Research Establishment but there were numerous technical difficulties with this. The radar set had to be made small enough to fit inside a shell, and its glass vacuum tubes had to first withstand the 20,000 g force of being fired from a gun, and then 500 rotations per second in flight. A special Section T of NDRC was created, chaired by Tuve, with Parsons as special assistant to Bush and liaison between NDRC and BuOrd.
On 29 January 1942, Parsons reported to Blandy that a batch of fifty proximity fuzes from the pilot production plant had been test fired, and 26 of them had exploded correctly. Blandy therefore ordered full-scale production to begin. In April 1942, Bush, now the Director of the Office of Scientific Research and Development, placed the project directly under OSRD. The research effort remained under Tuve but moved to the Johns Hopkins University's Applied Physics Laboratory, where Parsons was BuOrd's representative. In August 1942, a live firing test was conducted with the newly commissioned cruiser. Three pilotless drones were shot down in succession.
Parsons had the new proximity fuzes, now known as VT fuze, Mark 32, flown to the Mare Island Navy Yard, where they were mated with 5"/38 caliber gun rounds. Some 5,000 of them were then shipped to the South Pacific. Parsons flew there himself, where he met with Admiral William F. Halsey at his headquarters in Nouméa. He arranged for Parsons to take VT fuzes out with him on the cruiser. On 6 January 1943, Helena was part of a cruiser force that bombarded Munda in the Solomon Islands. On the return trip, the cruisers were attacked by four Aichi D3A dive bombers. Helena fired at one with a VT fuze. It exploded close to the aircraft, which crashed into the sea.
To preserve the secrecy of the weapon, its use was initially permitted only over water, where a dud round could not fall into enemy hands. In late 1943, the Army obtained permission for it to be used over land. It proved particularly effective against the V-1 flying bomb over England, and later Antwerp in 1944. The use of a version fired from howitzers against ground targets was authorized in response to the German Ardennes Offensive in December 1944, with deadly effect. By the end of 1944, VT fuzes were coming off the production lines at the rate of 40,000 per day.