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Dr. Alpher is an independent research consultant based in Austin, Texas. He is an elected member of the Society of Sigma Xi (Scientific Research Society). He has a long and distinguished career as a researcher and practitioner in psychological assessment and neuropsychology. He has published widely, including a number of recent works in Military History and the History of Science.

There have been many well-written and documented histories of torpedoes used before and during World War II Overall, torpedo performance was fairly dismal for all forces. One of the greatest problems in writing histories on such topics involves the classified nature of the original documentation. The Atomic Bomb is a good example. A lesser-known but no less decisive ordnance development during the war was the radio controlled Proximity Fuze. These tremendous advances in military ordnance were developed under the highest possible secrecy within the National Defense Research Committee (NDRC) and the Office of Scientific Research and Development (OSRD) under Vannevar Bush. They were founded by President Roosevelt in 1940.

This paper will demonstrate that torpedo development under the auspices of BuOrd was in fact much more successful than most experts have proposed, using primary documentation not previously considered. These developments were decisive in the Pacific, as were bombs and other ordnance detonated with the Proximity Fuze in Europe.

The Bureau of Ordnance Changes Gears and Adopts Modern Technology

Recruitment of the necessary scientists and engineers to accomplish the task of modernizing the American military occurred by word of mouth (or telephone) beginning on August 17, 1940. The first significant event was the hiring of physicist Dr. Merle Tuve by Vannevar Bush to head Section T. Section T contracts were of the most classified nature, and coveted throughout academia and industry. Employment interviews were held on the sidewalks of Washington, D.C., where “I have a job for you but I can’t tell you about it-oh, and you’ll need to move to Washington immediately with or without your family” was followed with the statement “I need your answer in two weeks.” Astronomer Dr. Ralph Belknap Baldwin was recruited three years after obtaining his doctorate in Astronomy at the University of Michigan (1937). One of his mentors, already working in Washington, Dr. Robley C. Williams, Sr. interviewed him on a sidewalk outside of the Carnegie Institution-the first physical location for Section T (Dr. Ralph Belknap Baldwin, personal communication, January 15, 2009). What Tuve wanted was good problem-solvers. One of the miracles of the War is that about 500-800 scientists and engineers, working under an unusually flexible bureaucratic structure developed by Tuve, were able to revolutionize ordnance provided to our military forces in a remarkably short period of time.3 Broad brush strokes of the nature of the advanced work were lauded in the years following the war. However, some technical details remain unknown or highly classified, even today. Some of the material used for the research documented here was not declassified until late 1996-and I was able to locate important details only because of very brief notes left by my father, who passed away in August, 2007.

The Low Point: The Early War Mark 14 Submarine Torpedo

The most common torpedo used early in the war was the Mark 14. This torpedo was a dismal failure, especially due to its deficient Influence (magnetic) Exploder Mark 6 which had problems comparable to those that plagued the German Kriegsmarine– inadequate depth control, duds, broaching, and a tendency to make a u-tum and return to the firing vessel. The contact detonator was not much better, particularly at small angles of attack. Karl Donitz referred to early German torpedo testing methods as “criminal”. In the U.S. Navy, early failures were typically blamed on the skippers, at least until the nature of the failures were carefully examined.

By early 1943, the Mark 6-equipped Mark 14 torpedo was no longer in use as it was designed. Often, the magnetic influence component of the Mark 6 Torpedo Exploder Mechanism was deliberately disengaged. Frederick J. Milford concluded his mid1990s series on torpedo development during World War II in THE SUBMARINE REVIEW that nearly exclusive focus on development of homing (sound-detecting) torpedoes following the Mark 14 debacle was not particularly successful. There was another concurrent track of torpedo development, typical of the OSRD, that was quite successful, however. In concept, what was needed was influenced significantly by the highly successful Radio Controlled Proximity Fuze. Its first appearance, as an anti-aircraft detonator was made on January 5, 1943. A Japanese dive bomber attacking USS HELENA was destroyed by a 5″/38 anti-aircraft (AA) shell.

Part of this new vanguard of scientists was my father, Ralph A. Alpher. From 1940 through 1955, he worked contracts with the Bureau of Ordnance (at the Naval Ordnance Laboratory, at the Carnegie Institution and the Johns Hopkins University Applied Physics Laboratory [JHUAPL] under BuOrd “Section T” contracts).

Reappearance of Magnetic Influence Exploders in 1944

Under Section T, for example, physicist Dr. Robert C. Herman, JHUAPL’s liason to the Navy, became after 1948 a lifelong scientific collaborator with R. Alpher in Cosmology. Astronomer Dr. Robert Belknap Baldwin was the liaison to the Anny, which had a dramatic effect on the end of the war in Europe. 12 As a Junior Physicist and Professional Engineer (he earned his Ph.D. in 1948 at George Washington University in Physics), R. A. Alpher was assigned to many different tasks. Because of his extensive experience with magnetism, his services were sought later in the war to assist with a new influence exploder for torpedoes. We tum now to that major project.

In April 1944 my father was first approached to move to JHUAPL. In a recommendation letter dated April 10, 1944 Scott Forbush, Ph.D. (on loan to the Naval Ordnance Laboratory from the Department of Terrestrial Magnetism of the Carnegie Institution) stated that R. A. Alpher had “far better knowledge of mathematics and physics than the average person with a Master’s.” He had also by this time acquired his B.S. degree in Physics (as well as the equivalent course work for a B.S. in Mathematics). On April 21, 1944 he received a formal letter of interest from the BuOrd Personnel Officer, A. Russell Slagle and Commander Arthur L. Wheeler, about an urgent task for which they stated, “We believe your qualifications are such that you would be of real value in the organization here.” They wanted only personnel who had the highest security clearance, and who would not be drafted, enlist, or in any way be open to enemy compromise.

This task was assigned jointly to the Applied Physics Laboratory of Johns Hopkins University (JHUAPL) and the Applied Physics Laboratory of the University of Washington (APLUW) which collaborated with the Naval Station at Keyport (Torpedo Town, U.S.A.). A mention of the coveted Section T contract is made in the January 1, 1945 “Lab Oratory” (Vol. 1, No. 1) of the APLUW. Ors. Wilbur Goss and Freeman K. Hill were the JHUAPL group supervisors. Eventually R. A. Alpher became Project Supervisor, Production Problems, during which he was responsible for introduction of any design changes, and production and testing problems. He began working with the group on August 1, 1944. On June 20, 1946, Dr. Wilbur Goss applied for a Patent for “an exploder for a torpedo and more particularly to an improved exploder of the influence operated type.” (United States Patent Office, Patent No. 2,968,242 awarded January 17, 1961; interestingly, the patent for the Proximity Fuze involved an extensive legal battle in the 1960s).

That “Special Torpedo”

I will briefly describe the advantages of a newly formulated magnetic influence torpedo exploder, introduced in OP-1365 written by my father and published by the Bureau of Ordnance with the date March 13, 1945. I will confine most of my remarks to the Mark 9 Mod 0, although in 1950 OP-1365 (First Revision) for the Mark 9 Mod 3 was also published, summarizing improvements made following the introduction of the novel and successful Torpedo Exploder Mechanism (TEM) Mark 9. In the Preliminary OP-1365 my father wrote:

“There are basically two advantages in the use of the influence exploder. First, the target, as seen by the exploder, is effectively increased, since it is unnecessary for the torpedo to actually strike the target. The extent of the target’s magnetic field makes exploder operation possible at reasonable depths below keel depth. Second, if the torpedo is run at target keel depth with the proper time delay in the action of the exploder, the explosion will occur either beneath the target, where the maximum damage possible will result, or else a low contact hit will be obtained” (most vessels of the period were better armed at the side, expecting side contact from shallow-running torpedoes).”

Prior to his passing in 2007, he described many of the dangerous experiences he had experimenting with early versions of the new TEM 9 in tests in waters off the State of Washington (most likely Puget Sound). There, he and his colleagues observed and tested torpedoes in the running, occasionally having to abandon their wooden boat as a torpedo broached out of the water, veered off course, or otherwise threatened the testing crew in some manner. He carried a mercury-filled Navy-issue lamp that emitted a faint blue glow for nighttime rescue (see Figure 1). He remained with this research and development group full-time until September, 1945, but thereafter continued to make further contributions on an as-needed basis.

Magnetic Influence Exploders in Greater Detail

The main design feature of magnetic Torpedo Exploder Mechanisms (TEMs) is the method of detonation (of course, all such torpedoes can also be detonated by direct contact). Several problems attendant to prior torpedoes other than the influence component had to be solved. First, the torpedo must run at a constant depth, preferably under a ship’s keel, breaking its back in Naval parlance. The Mark 14 had been found to run many fathoms deeper than set, inflicting minimal damage even when detonated. A direct under-keel detonation is magnified by the plume from the explosion, however.

The new TEM included two coiled electromagnets with reverse polarization (providing the information to the gradiometer that initiated the firing sequence). The design was completely novel. It also required a seaworthy battery- activated by seawater after launching– that would not arm the mechanism until it was a safe distance from the launching vessel (later versions were armed mechanically in such a way that minimal deviations off-track would be insufficient to operate the electric cap). The new gyro had adequately to control yaw, pitch, and roll to control the torpedo’s depth and angle of approach.

Second, a new gradiometer was added lo the detonation sequence to detect polarity changes. It turned out that deficiencies of the early Mark 14 were due not to human error, but use of the torpedo in equatorial waters far away from its design features hence, the geomagnetic field was considerably weaker providing insufficient information to arm the torpedo. The use of any such detonator must be calibrated to the effects of the influence of the earth’s magnetic field on the target and the torpedo. Even a degaussed target will acquire a new magnetic signature from the pounding of waves, firing of guns, as well as passing through the earth’s own magnetic field (Ralph A. Alpher, personal communication, December 3, 2005). The early Mark 14 influence design was not sophisticated enough to account for all of these variables. He described to me an experiment trip made on USS MASSACHUSETTS from Virginia to New York to measure the effects of wave pounding, 16-inch gun firing, AA gun firing, and passing through the Earth’s own magnetic field on the ship’s magnetic signature.

Third, a mechanism was necessary to keep the circuit from accidentally closing if the torpedo was jarred or flexed in transit. This would occur, for example, if a German or Japanese magnetic mine exploded as the torpedo passed by. This problem, though complex, was solved by deactivation of the influence feature from shocks of sufficient severity as to flex the warhead. This was called a “CC” or ceiling-countermine switch (broaching could also cause sufficient flexing as lo cause premature detonation). The firing condenser was bridged with a 10,000 ohm resistor when the torpedo reached the surface, preventing detonation. Further, another set of contacts short circuited the firing condenser when closed by a shock wave or by high pressure. This helped avoid premature firing due to a variety of environmental threats in the ocean.

Fourth, closure of either set of contacts would activate thyratron tubes leading to activation of the firing mechanism (late in the War, Torpex was preferred for underwater explosion). Sufficiently rugged thyratron tubes had been developed for the Proximity Fuze. Activation of the firing sequence could only occur when the torpedo came close enough to the keel of a ship or submarine, where the magnetic field encountered has sufficient perturbation (measured in gauss).

Fifth, the TEM 9 had many intended applications. This included the Mark 13, 16, and 18 War Heads. The first application was to be on the Mark 13 Torpedo {Bureau of Ordnance OP-1365 ([Preliminary]) TORPEDO EXPLODER MECHANISM MARK 9 MOD 0, 13 March 1945), an air-to surface anti-submarine and anti-ship torpedo. Further applications were anticipated for the War Heads Mark 18 Mod 3 and Mark 16 Mod 5 as stated in the OP and are described in the First Revision. The Mark 13 was the mainstay of the Navy’s Avenger torpedo bomber, which was used extensively in both Pacific and European theaters.

In the introduction to OP-1365 (Preliminary) Rear Admiral G.F. Hussey, Jr., Chief of the Bureau of Ordnance stated: “Because of the urgent need for this information, it has been issued in preliminary form.” {p. ii). Unique testing devices were developed so that an experienced radioman could regularly monitor the proper operation of the many components of TEM 9 (Supplement to Ordnance Pamphlet 1365, dated August 1, 1945). Because of its unique characteristics, even ship degaussing was an ineffective countermeasure for the TEM 9- the Germans and Japanese were known to have employed degaussing when building ships, when the first magnetic signature is acquired, although neither opponent required repeated degaussing at a frequency of six months as required and monitored by BuOrd.

What is the World War II Record of the Mark 9 TEM?

Many reports are silent as to the use of the Mark 9 TEM during World War II. 14 One would have expected it to be used with the Mark 18 Torpedo because the Mark 18 became more popular after the Mark 14 debacle, and because of its deep, wakeless running. In this way the adaptation of the German G7e electric torpedo with U-570 captured by the Royal Navy in 1941, and manufactured first in the U.S. by Westinghouse was well done.

The prototype Mark 9 TEM was first tested against the 10,000 ton German oil tanker AMPETCO (the second of three by that name, manufactured in 1926 in Kiel). Off Aruba, the hulk of this tanker which burned in a collision in 1944 sank in 10 minutes. 16 My father’s photograph of this test clearly shows a shallow running torpedo, most likely a Mark 13 fired from a Naval Avenger.

There is now convincing information that the Mark 9 TEM made a decisive impact during the final year of the War in the Pacific. On April 7, 1945, barely a month after the publication of the initial OP-1365 for the Mark 13, the largest battleship ever built, the Japanese YAMATO ( 1941) was sunk along with several other Japanese warships (operation “Ten-Go”) after first being sighted by a submarine in an excellent coordination of submarine with Naval Aircraft Carrier Task Groups 58. YAMATO herself was struck by some ten Mark 13 torpedoes launched by TBM Avenger Navy torpedo bombers. The improved Mark 13 was probably introduced sometime sooner, but nonetheless, the Japanese fleet was rendered ineffective as an attack force for the remainder of the war. Beginning with the Mk 13 Mod 0 through Mk 13 Mod 13, about 17 ,000 of these torpedoes were manufactured during the war. 19 The combined magnetic influence-contact Mark 9 Torpedo Exploder Mechanism was designed initially to be used with the Mark 13 Mod 4. Had the intensity of the Pacific Naval campaigns continued, I would think there would be little doubt as to its use in Mark 18 Mod 3 and the Mark 16 Mod 5 as initially intended although primary documentation has not yet been found to support any speculation.

My father received the Naval Ordnance Development Award (with symbol) signed on December 10, 1945 by then Rear Admiral G. F. Hussey, Jr., Chief of the Bureau of Ordnance. In a separate letter with the same date, also personally signed by Admiral Hussey, the Admiral added to the body of various commendations “The congratulations of the Bureau of Ordnance are extended to you for your outstanding performance in connection with the research and development of a special torpedo [emphasis added; the nature of the reference implies its classification].” The Mark 18 was the preferred torpedo toward the end of the war; during the last 6 months of the war, 65% of the torpedoes used were of the Mark 18 type. Gannon, interestingly, does not even list the Mark 18 as being in any stage of development at the end of the War.

In addition, a memorandum dated July 9, 1945 from Admiral Hussey to the Officer in Charge, Naval Ordnance Laboratory, Navy Yard, Washington 25, D.C. Stated the following:

Subject: Mine Performance

1. This Bureau is in receipt of information from the Pacific indicating that mines developed by the Naval Ordnance Laboratory and planted in Japanese home waters have and are currently taking heavy toll of enemy shipping and have disrupted Japanese industry by blockading large numbers of ships.

2. The Chief of the Bureau of Ordnance notes with pleasure that the Naval Ordnance Laboratory was singled out for congratulations for effective mine designs by the command responsible for laying the mines.

This memorandum, although stamped 9 JUL 1945 had a second half, stamped I 0 AUG 1945. It continued:

From: Officer-in-Charge, Naval Ordnance Laboratory.
To: Ralph A. Alpher

3. The achievements cited above represent the culmination of five years of vigorous industry enthusiastically and intelligently applied, carried forward with perseverance in the face of many formidable obstacles, by a superb team of scientists, engineers, technicians, artisans, and administrators.

4. I take great pleasure in congratulating you as a member of that team for your part in bringing about this important contribution to the winning of the Pacific war.

The bottom portion of this combined memorandum was signed W.G. Schindler, Captain, U.S. Navy, Officer-in-Charge, Naval Ordnance Laboratory. It reflects not only Ralph A. Alpher’s work on degaussing, the Proximity Fuze, and the Torpedo Exploder Mechanism Mark 9, but work on mines and mine countermeasures as well. Interesting to note is that on May 3, 1946, the Applied Physics Laboratory presented my father with a second Naval Ordnance Development Award lapel pin (letter of May 3, 1946 signed by D. Luke Hopkins, who was on the Board of Directors of Johns Hopkins University).

Following World War II

On October 28, 1947 (letter from R.E. Gibson, then director JHUAPL) my father was assigned part time to the High Altitude Research Group under Dr. John A. Van Allen. From examining the nature of his writing and the actual publications, I have little doubt that Ralph Alpher contributed extensively to the First Revision of OP-1365, TORPEDO EXPLODER MECHANISM MARK 9 MOD 3, dated May 11 , 1950. I have not yet located copies of MODS 1 and 2. (This Revision was in a National Archives Record Group Box that was only Declassified December 18, 1996). This version had additional novel components. One made it feasible to “set torpedoes carrying the exploder to run deeper than for contact shots, thus giving better torpedo depth keeping performance against shallow draft targets.” (Chapter 1). MOD 3 also permitted installation in combination with several different torpedo War Heads with no modification whatsoever.

The addition of a degaussing loop for the Mark 18 Torpedo, because it was electrically driven, was added as a safety precaution because of fluctuations in amperage in the battery compartment that could cause premature detonation. This was not unlike that used to degauss the cathode ray tube used in early televisions and was situated between the battery compartment and the Torpedo Exploder Mechanism.

As you can see from the cutaway (Figure 3), the full works of the Mark 9 Mod 3 TEM appear present in a photo that was also printed in a 40-year history of the JHUAPL. Following the war, the new principles applied to replace the faulty Mark 14 Mod 6 that led to such havoc in 1941-43 were continued. As is clear from the histories put together by the NDRC of the extensive Antisubmarine Warfare (ASW) and Submarine Warfare advances during the war, changes developed by the OSRD during the war continued to flourish. My father, for example, continued to work on these projects for many years at JHUAPL until leaving for the General Electric Company-yet even there, he was extending immediate post-war research (Ram-Jet, Terrier Missile, Shock Tubes) and magnetism (Magnetohydrodynamics) to problems initially identified by BuOrd and given the highest priority for solution during the war. Figure 4 shows application of the Mark 9 Mod 3 in three different torpedo warheads from the OP-1365 of 1950. Readers of this Review, probably more than any other group, will certainly recognize that these principles have been incorporated in subsequent ordnance to this day.

Another Magnetic Influence Exploder, the Mark 10 Mod 3, was introduced prior to April 15, 1945. Reference to it, and to the Mark 9 Mod 0 and Mark 9 Mod 1 appear in the Mine Disposal Handbook, Part II. Chapter 3. U.S. Torpedoes from the United States Underwater Ordnance Bureau. The initial Handbook is dated October 1, 1944, with inserts added April 15, 1945, June 10, 1945, and September 1, 1945-to aid in disarming torpedoes, many models are explained in detail so that they may be rendered safe. The vast amount of information included in this Handbook merely supports the main thesis of this paper, that Magnetic Influence as a detonation device hardly ended with the demise of the Mark 14 Mod 6 Submarine Torpedo of the early war. (Ed. note: emphasis added).

It is my hope that new information about torpedo development under the Bureau of Ordnance wilt encourage others to delve into the as-yet unwritten history of World War II and post-war torpedo development . We should not forget the dedication of millions, from the smallest hands needed to work on the Proximity Fuze to the brilliant minds that were gathered to solve ordnance and other wartime problems. Our great nation dedicated itself to end that conflict so that our rare system of freedom, democracy, and self government might survive. Tyrants of the 20th century did not believe a system such as ours could accomplish these tasks. Great dedication in the 2151 century will be needed to preserve it.


Much of this work would not have been possible without the assistance of many individuals- more than I can possibly name here. Most important was the assistance of Mr. Jack Lopez, USN Ret., President of Aviation Archives in Potomac, Maryland. The Historic Naval Ships Association (Rich Pekelney in particular) was most helpful. Many articles in The Submarine Review have helped me see how the importance of this gap in reported torpedo research and use should be recognized.

Further, support of many relatives, friends, and colleagues have inspired me during long periods of slow going and bursts of activity and enthusiastic progress. Such is the nature of scholarly research. Foremost amongst these is Professor Dwight (Ed) Neuenschwander. Also, I acknowledge Gerard G. Connors, Ph.D., Lt. Col. C. Jay Lyons (U.S.A.F.-Retired), Tatyana Zayeva, Bill Henry, Ph.D., Norman and Deanna Alpher, Rita Alpher, and Gary White (American Institute of Physics and Sigma Pi Sigma). My father’s friends and colleagues Drs. James Van Allen, Ralph Belknap Baldwin, Bob Herman, Don White, Bob Johnson, Charlie Muckenfuss, and Samuel Wait, and my longtime friends, Bill Erickson, M. J. Valachovic, Richard B. Hook, Jr. have all helped further this research.

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