The nuclear weapons of the united states navy 1945 – 2013 Don G. Boyer Haleiwa, Hawaii March 2013
Download 182.12 Kb.
|
- Navigate this page:
- The Mk 5/B-5
- Part 4: More Bombs The MK 6 Bomb
- The MK 7 Bomb
- The MK 8/B-8 “Elsie” Bomb
- The B-11 (MK 91) Bomb
- The MK 12 Bomb
- Part 5: The Beginning of the Megaton Era
| Part 3: The First “New” Bomb
By the early 1950s, the U.S. Navy had established itself as a nuclear-capable force, with delivery aircraft in production and ships modified to store, assemble and deploy nuclear weapons. Only the large, cumbersome Mk 3 and Mk 4 bombs were available for use, and these weapons were by no means ideal for military service due to their short “shelf life” once assembled, the labor and manpower-intensive process of assembly and test and of course their weight and size. The main delivery aircraft operating from carriers was the AJ Savage, a huge and cumbersome aircraft for use on a carrier. Even the large Midways had problems with those aircraft in handling and storage. Still, the navy could deliver nuclear weapons to the maximum range dictated by the Savage (2,470 miles carrying one Mk 5) or the longer-ranged P2V. While the P2V Neptune ASW/patrol aircraft could also carry the current nuclear weapons, and several aircraft were modified for this duty, the advent of the Savage and even more capable aircraft over the next few years kept the P2V pretty much on the periphery of the nuclear strike picture. They would probably only have been used for the ultimate emergency. This section continues covering the bombs used by the Navy, from oldest to newest, and will be followed by the navy's anti-submarine weapons, missiles and lastly the strategic ICBM/IRBM warheads. Each section will cover the weapon (bomb/warhead) itself and, briefly, the delivery system for that weapon, be it an aircraft or other system. (Bombs and warheads are basically synonymous, whereas other nuclear delivery systems are not so congruent.) One of the difficulties with nuclear delivery systems is the official designations assigned to them. The designations for aircraft have changed at least twice since the end of WWII and the designations for missiles and other systems have also been prone to bureaucratic revisions over time. Here the specific designation for the aircraft/weapon in use at the time the weapon was in the active inventory is used, since everything is pretty easy to find on the web. If there was a “popular” name for a system, that will be included (“Lulu” “Hotpoint,” etc.). Just to make matters even more complex, there are the designations applied to the actual weapons themselves, which can be somewhat interchangeable – “B” for bomb, “W” for warhead, and the MK (Mark) identifier used with many weapons. (The MK 101 “Lulu” is a good example – the navy designated it as the MK 101 depth bomb, but it never carried a “B” designation, and it had the W-34 warhead as its nuclear component.) Based on the new nuclear bombs entering the inventory early in the 1950s, it becomes obvious that the military and scientific communities were closely collaborating on weapons designs in order to reduce weapon size, increase availability times, ease the job of delivering weapons, reduce the risk to the delivery aircraft, and increase the safety factors involved in handling weapons. Up to this point, the military had to basically accept what the weaponeers and scientists had been able to design given the known physics and engineering capabilities of the time. That would now change, as the military began to understand nuclear weapons physics and mechanics, enabling them to specify exactly what they thought was needed to ensure they could deliver the goods against an enemy target. It was a slow process, but the scientific community was well capable of the science and engineering necessary to produce these weapons in amazing variety and pretty consistent high quality to meet specific military needs. Progress in weapons manufacture was greatly aided by the fact that nuclear weapons had about the highest budget priority there was for many years, money spent not only on weapons but the manufacturing infrastructure as well. (The ability to reduce the size of both fission and fusion weapons over the past 60 years has been staggering, and has used a variety of techniques, some still highly classified. The early improvements revolved primarily around developing better high explosive packages using new types of explosives coupled with reducing the size of detonators and their electrical harnesses. Weapons also benefitted from being able to reduce the size and weight of the weapon's electronic and other systems. Early yield increases for fission weapons usually revolved around better nuclear capsule designs and the ability to “boost” yields by various means, usually gas boosting using tritium and/or deuterium.) The Mk 5/B-5 In 1948, the Los Alamos laboratory began design work on a new bomb that would be a big improvement in some areas over the Fat Man derivatives then in the stockpile. The warhead component was tested during Operation Greenhouse, Test Easy, on 21 April 1951. With a test yield of about 47 kt, the weapon had about doubled the output of previous weapons. The test device became the Mk 5/B-5 bomb, which entered the inventory beginning in May of 1952 and was the first lightweight small diameter nuclear weapon. Weighing between 3025 and 3175 lbs depending on Mod and core, the weapons was 10' 9” long and 3' 8” in diameter. The bomb version used composite cores and had variable yields of 6, 16, 55, 60, 100, and 120 kt. The Mk 5 was the first weapon to use an automatic IFI instead of the previous method of hand-inserting the core into the weapon. The automatic IFI had the core installed in a separate holding tray when the bomb was prepped; this kept the core away from the high explosive package. The tray would insert the core in the bomb at the appropriate time by electrical command from the aircraft. For a nuclear weapon to work the core must be exactly centered within the high explosive package in order for implosion to occur; any other arrangement, such as when the IFI had the core outside the weapon, would not cause a nuclear detonation if the weapon explosives detonated in an accident scenario. While there would be a local scattering of highly radioactive materials about in this situation, that would be a far better scenario to clean up than an accidentally incinerated military base and city. The PR would be easier to deal with as well. About 140 Mk 5 weapons were produced in 1952-53 and these weapons eventually had four Mods. (As with many weapons, later Mods were usually made from the major components of the previous version, with whatever improvements of the new Mod added in. Old Mods would “retire” new Mods would take over, and the inventory remained about the same). The bomb was somewhat restricted in use because it was limited to high-altitude delivery and was fused only for an air burst option, there were no contact detonators. The bomb was internal carry only, and thus could not be used with supersonic aircraft. With no competing weapons in the inventory at the time, these limitations were moot. A Mk 5 was used as the “primary” (nuclear fusion initiator) in the early Ivy Mike thermonuclear test on 1 November 1952. The nuclear package was also adapted as the warhead for both the Matador and Regulus missiles and these bombs were also supplied to Great Britain under Project E for use with the Valiant bombers. The B-5 was withdrawn from inventory starting in 1957, with the last weapon retired by 1963. During this bombs active service with the navy, the AJ-1 and -2 Savage was the primary carrier, bolstered by the all-jet A-3 Skywarrior which was a far superior aircraft capable of 620+ mph and with a 2,300 mile tactical range. The Skywarrior came into service in 1956, just before the MK 5 was starting to be withdrawn from service. Part 4: More Bombs The MK 6 Bomb The MK 6 bomb was the first American nuclear weapon to be produced in large numbers, with around 1100 built between July 1951 and April 1954 – and indication of the ability of the weapons manufacturing infrastructure to meet what were felt to be the needs of the nuclear stockpile. The MK 6 was 10' 8” long and 5' 10” in diameter and weighed between 7600 and 8500 lbs depending on the core used. An obvious lineal descendant of the last “Fat Man” type bomb, the MK 4, the Mk 6 was a far better weapon, providing greatly increased yields at considerably less weight. Up to 3000 lbs of weight had been saved by making the bomb casing out of aluminum instead of 3/8” mild steel. The MK 6 was produced in four Mods. Weapon yields varied depending on the core used and were 8, 26, 80, 154, 160 kt. (I've never been able to figure out why a weapon would have high-yield cores whose difference in yield would only be about 6kt. “What's the point?” comes to mind). One of the improvements of the MK 6 over the MK 4 and 5 was the ability to alter the burst altitude of the weapon in flight. It also had a contact fusing option in addition to the airburst option. The bomb's main drawback (and that of its upgraded sister, the MK 18, discussed later) was the fact that it used large amounts of fissionable material (plutonium) to achieve the higher yields. As the newer, lighter weight fission weapons became available, along with the first thermonuclear weapons, the Mk 6 started to be withdrawn from service as early as 1955 for the Mod 1 and by 1957 the last Mod 4 had been retired. The cores of these weapons, like many others were refurbished and used in other weapons and the Mk 6 bomb casing was used for the newer Mk 18 bomb. The bomb could be delivered by the AJ Savage and A3 Skywarrior. The MK 7 Bomb The MK 7 bomb was the first of the true “tactical” nuclear weapons (not designed for the strategic attack role) deployed by the United States and the first to be used by all three armed services. In addition to the bomb version, the warhead was also used in the Army's Corporal and Honest John missiles and in the Navy's BOAR (Bureau of Ordnance Atomic Rocket) and the Betty depth charge (both will be covered later). The MK 7 was designed for external carriage by fighter/attack aircraft and had a retractable lower fin so that the bomb would not “scrape” during a catapult launch. Measuring 15' 3” long by 31.5” in diameter and weighing 1645 – 1700 lbs, the bomb had five yields – 8, 19, 22, 30 and 61 kt. Produced in 10 different Mods, the bomb was in the active inventory from 1952 – 1967. Versions of this weapon were supplied to Great Britain under Project “E” for the Canberra B(I).8 from 1960 – 1968. This weapon could be carried by a wide selection of naval aircraft, including the AD, A3P, AJ, F2H (Banshee), F3H (Demon), F7U-3 (Cutlass), P5M (Mariner), P2V (both the bomb and the Betty depth bomb), S2F (Betty) and even the HSS-1 helicopter (Betty). About 1800 MK 7s were produced. The MK 8/B-8 “Elsie” Bomb The MK 8 bomb was the first “penetrator” bomb. Nicknamed “Elsie” for “LC” (light case)” the MK 8 was developed at Los Alamos specifically as a naval weapon for use against “hardened” targets like submarine pens. A much-improved “Little Boy” gun type weapon not so wasteful of fissile material, it was the first nuclear weapon designed to detonate after hitting the ground as opposed to an airburst or instant ground contact detonation, being equipped with a delayed action fuse. The bomb was 9' to 11' long and 14.5” in diameter. The yield was variable between 20 to 30 kt. The weapon could be carried internally or externally, but was not designed for supersonic speeds and was therefore quickly replaced in the inventory by the later B-11 (also known in the Navy as the MK 91). Only about 40 MK 8s were produced between 1951 and May 1953, with the last weapons withdrawn from the inventory in May 1957. They could be carried by the AD, AJ, A3D, A4D (Skyhawk, later A4), F2H, F3H and F7U-3. The B-11 (MK 91) Bomb The MK 91 bomb was an improved MK 11 gun-type penetrator weapon which had a sharp heavy nose, unlike the flattened nose of its predecessor. Also a Los Alamos design, the bomb was credited with being able to penetrate 22 feet of reinforced concrete or up to 120 feet of clay soil, far exceeding the capabilities of the MK 8. It could also be carried externally at supersonic speeds. The bomb had a delayed action fuse that would detonate up to 2 minutes after impact. Like the MK 8, only about 40 of these weapons were produced through 1957 as lightweight thermonuclear weapons came on line such as the MK 43, which also had some penetrative capabilities. By June of 1960 these bombs had been removed from the active inventory. The MK 11 was 12' 2” long and 14” in diameter, weighing up to 3500 lbs. and had a variable yield between 10 and 20 kt. The bomb could be carried by the AD, AJ, A3D, A4D, F2H and F3H. The MK 12 Bomb The MK 12 bomb was developed by Los Alamos in response to a Navy requirement for a light tactical weapon that could be delivered by supersonic fighter aircraft as well as subsonic attack aircraft. A major improvement over the MK 7, the Mk 12 could be delivered at speeds up to mach 1.4 and had the same fusing options – air and ground burst. Produced in three Mods, the MK 12 was 13' long and 22” in diameter, weighing 1200 lbs. Yield was 12 or 14 kt and the bomb was reportedly the first to use a beryllium tamper to reduce yield. (A "tamper" absorbs neutrons, making less of them available for the nuclear chain reaction, causing less efficient nuclear burning and a reduced yield. Boosting has the opposite effect.) The bomb first entered the inventory in 1954 and was finally retired by 1963, some 250 bombs having been produced. Though the bomb was an improvement on the MK 7, it did not replace the MK 7, merely supplemented it. Delivery aircraft were the AJ, A3D, A4D, F9F-8B (Cougar), F3H, F7U-3 and FJ4-B (Fury). Part 5: The Beginning of the Megaton Era Before continuing on with the eight remaining nuclear bombs available to the United States Navy during the nuclear era and then on to missiles and other weapons, we should step back a bit from bomb production and take another look at the historical context within which the nuclear weapons program evolved from the early 1950s to the present. The transition from the early fission weapons to far more destructive fusion weapons is a good starting point. By the early 1950s, the thermonuclear weapon had become a reality. The principle of nuclear fusion developed by Stanisalw Ulam and Edward Teller that provided the method by which a nuclear detonation could initiate thermomuclear burning resulted in early devices being tested by the United States beginning in November of 1952 at Bikini and Eniwetok; at first a cryogenic proof of theory test (using liquid deuterium and tritium, totally impractical as a bomb) and shortly thereafter the first "dry" lithium/deuterium weapon which is the working principle of all subsequent thermonuclear weapons. At first these "H-bombs" were huge and could only be carried by the Air Force's B-36 bomber, such as the 21-ton MK 17 with its 13.5 MT yield (MT = one million tons of TNT). In one gesture of a magical arm, the nuclear genie had upgraded itslef from being able to incinerate most of a city to completely incinerating a huge piece of real estate from the face of the Earth and poisoning it beyond habitation for many years to boot – a rather scary proposition at best. Methods for reducing the size of these thermonuclear bombs were rapidly developed for bombs and missile warheads, the process evolving even faster than that for fission weapons which, for example, had reduced the first Fat Man type bombs with roughly a 20 kt yield for almost 10,000 lbs of bomb to around 60 kt in a bomb weighing about 1700 lbs. by 1952. It was only a few years before the American military could field weapons with yields of 2 megatons in a weapon weighing around 3300 lbs and deliverable by even the smaller tactical aircraft as well as the big bombers. (The development of missiles to deliver comparatively lightweight warheads also proceeded apace, with the emplacement of the first ballistic missiles able to deliver thermonuclear destruction from thousands of miles away just a few years in the future.) Many factors went into the reduction in size, including "smarter" methods of initiating and sustaining a fusion reaction, reducing the size of the nuclear "primary" in a fusion weapon, and of course huge advances in miniaturizing the electronic and mechanical "packages" that controlled a weapon and permitted it to detonate when all factors had been successfully input into the arming and fusing system, factors that included ever more effective and sophisticated safety parameters. Congruent with the development of the thermonuclear weapon were great improvements in the "standard" fission weapons of the day that greatly increased their yield with little modification to the weapons internal systems, particularly the use of "boosting" systems. The necessary combination of a fission primary to initiate thermonuclear burning in a fusion "secondary" also allowed for more options in the deliverable yield of weapons, yields which could eventually be adjusted within certain parameters as needed prior to the weapon being delivered. It is to be noted that the Soviet Union, aided by their continual espionage, but in the end independently under the guidance of the brilliant Igor Kurchatov and his successors, were able to develop their own thermonuclear weapons and pursue their own "arsenal of communism" while we pursued our "arsenal of democracy". The idiotic levels to which this pursuit was carried only became apparent on both sides of the Iron Curtain much later, particularly after the Cuban Missile Crisis wake-up call for both sides. Concurrent with the development of thermonuclear weapons were the development of versions of these weapons that would create far more human destruction and less physical destruction (the so-called "neutron bomb") as well as even worse scenarios that would salt the Earth with fatal levels of radiation for many years ("dirty" bombs). While the former might have some military merit, the latter was just plain stupid. Yet those weapons either entered the inventory or existing weapons could be quickly modified to these standards if needed. The advent of thermonuclear weapons had clearly escalated the potential to wipe out the human race from a probability to almost a certainty, along with wiping out almost everything else that lived and breathed. Thermonuclear weapons brought about the absurdity of having weapons to "protect" a nation that could eventually wipe that nation out even if used only against an enemy thousands of miles away, not even counting the results of that country's nuclear response in the equation. This is not a good set of parameters to use in measuring the potential for humans to outgrow their tendency to slaughter each other on the flimsiest of religious or social pretexts and evolve into their much-avowed potential to be peace-loving and productive products of evolution. Of course, this "nuclear winter" scenario that thermonuclear weapons had made possible was not recognized or even readily apparent in the 1950s and early 1960s – when the free world approached its most dangerous crisis with the American military quite willing to commit to nuclear war should the "other side" make a fatal misstep with their nuclear weapons in Cuba. This makes that narrow miss even more historically relevant than just the potential for a nuclear exchange. Fortunately, the Cuban crisis, coupled with growing scientific recognition on both sides of the Iron Curtain that we were setting ourselves up for total elimination as a species finally got the lights on, and led directly to the tentative steps at nuclear reconciliation that now hold among the governments of the world – barely. The concept of "MAD" – mutually assured destruction – that evolved in this era as the justification for the massive nuclear arsenal could not have been more aptly named. It was infantile in the extreme as a policy designed to deter evil and the horrors of nuclear war. The policy could not prevent war, just make sure there were no winners, and even politicians and statesmen can recognize the folly of no-win situations. But, in the meantime, nuclear testing of fission and fusion weapons continued apace at Bikini, Eniwetok, Nevada and a few other places (very few) and of course the Russians had their own program of incinerating test sites with gay abandon as well. The United States confined their surface tests of thermonuclear weapons to the Pacific Islands (managing to poison several islands and their inhabitants in the process) while the Russians basically set off whatever they wanted in their interior test sites regardless; the prevailing winds blew toward China anyway. Most of these tests were more "proof of systems" tests – i.e., proof of the operating/delivery system, be it a bomb or missile – rather than any proof of the fission/fusion process, although refinements were made in these areas as well as scientific knowledge grew. The Soviets, ever anxious for the communist system to "top" that of the obviously doomed and decadent imperialist West, eventually detonated a 58 MT air-dropped thermonuclear weapon (the Tsar Bomba) over Novaya Zemlya, proving to the world they were without doubt the biggest and baddest kids on the block and ready to rule the world as soon as everybody else kow-towed to their obvious might. (The unfortunate difference between fusion weapons and fission weapons is that while fission weapons are limited to a top end around 500kt, thermonuclear weapons have no top end. The Tsar Bomba was actually a reduced version of the original proposal which would have yielded 100 megatons.) Probably the only things that Soviet test proved was that you could punch a hole in the Earth's atmosphere all the way to the edge of space and irradiate a huge area for no good reason whatsoever. Communism at its best, in other words. Anyone who uses Google Earth to take a look at the massively cratered Nevada Test Center northwest of Las Vegas, Nevada or the islands of Bikini and Eniwetok will get a good idea of the extent of this testing. In my opinion, a lot of the testing was in the end unnecessary, particularly above ground tests, but it seems the paranoia generated by the conflict between the communist world and the free world knew no bounds in those days. The frantic military scrambling to avoid any "bomber gap" or "missile gap" and to prevent communist domination of the world powered the government into total overkill, some of this partly because the military was trying to justify its existence and budgets regardless of the actual threat posed by the opposition, a fact that began to become apparent when spy planes and satellites started to reveal the true decayed situation within the Soviet Union for all to see. Bomb shelters and "duck and cover" nuclear paranoia and absurd sci-fi movies featuring giant insects run amok abounded in the America of the 50s and, again in my opinion, were useless in facing up to the obvious. The only possible reason I can think of to duck and cover in those days would be to kiss your sorry ass goodbye. The same criterion applies today. And humans, obviously, are inherently far more dangerous antagonists than any oversize Technicolor ant could ever be. Even Godzilla knows that. Complimenting the absurdity of so much testing of weapons was the equally absurd (again, in my opinion) approach of the American government to the safety of these tests in regard to the public at large. (The Soviet and its successor government's response was even more absurd – they didn't care then, and care even less now.) One can draw a comparison to the destruction of two Japanese cities, with the subsequent radiation poisoning and death of thousands not directly or fatally exposed to the blast and heat of the detonation over a period of years to the assumption by the government that detonating even larger weapons within a few hundred miles of population centers like Las Vegas and cities "downwind" of the test site posed no real risk to the public, despite the even more recent examples of events at Bikini and nearby islands compounding the evidence found in Japan. Coupled with this has been the continual foot-dragging of the government in recognizing the effects of these weapons tests on the thousands of military personnel and civilian workers who participated in these tests as well as the Pacific islanders affected by fallout. Some compensation has been granted in various forms to the nuclear veterans groups following what little was done for the Pacific islanders. The plight of the South Pacific islanders has been well-documented in a book on the subject, that of the nuclear veterans less so. It's still a struggle, but progress has been made, far too late and I'm sure many dollars short for many. Like many governments the world over, ours is sadly no different in their reluctance to admit mistakes that adversely affect the health of the population and even more reluctant to open the coin purse `in compensation. While one can justify the existence of nuclear and thermonuclear weapons as a means of ultimate defense against the encroachment of total evil, justifying the quantities of weapons needed to achieve this goal, and the methods of testing these weapons is not subject to the same easy logic and justification. We managed to poison our environment with these weapons just by testing them, without having ever gone to war with them. That's pretty stupid by any criteria of evaluation. While the absence of nuclear war has been a nice bonus of the latter half of 20th century history, we could have done completely without the extremes of poisonous testing. However, humanity, ever willing to postpone serious decisions in the hopes the problem goes away and thereby learning the hard way that such policies only mean having to make harder and far less palatable decisions from among far worse options later, has finally signed treaties and reduced arsenals from the world-obliterating numbers of the past. The communist system collapsed under the weight of its own financial burdens and from the fact that the Soviet world and its imitators were not communist systems but rather systems of harsh totalitarian government by a privileged and criminal few – the diametrical opposite of what Marx and Engels had proposed. The free world came out on top because freedom is just so much more fun than totalitarianism for all concerned, and learned that it did not need an arsenal that could destroy the entire world fifteen times over, did not need to spend trillions of dollars as a hedge against "the other guy." The Soviets went under simply because their system, regardless of how much it was forced to function by the threats of the gulag and the basement of the Lubyanka, simply would not. With that historical turnaround in hand, we now only face the modern and possibly more dangerous absurdity of having to share our world with fanatical religious zealots who are convinced that only their religion should reign supreme, and that possession of nuclear weapons might go a long way toward realizing that goal. They see only the weapons themselves as an adjunct to the Sword of Allah, a threat to be bandied about along with their concept of jihad against more libertarian principles; they do not see the lessons that the development of nuclear weapons taught both the now defunct Soviet Union and the United States. This makes them far more dangerous than our former antagonists because they are, in the end, not very bright when it comes to the lessons of history, and are only interested in promoting themselves as the epitome of human social and religious evolution regardless of any potential consequences. This highly unstable and erratic view held by a considerable majority in the Islamic world is extremely hazardous to the overall health and well-being of the world in general, and themselves in particular. These wielders of jihad and absurd social conservatism have about them the same suicidal flavor of Japan's old Imperial Army, willing in the end to face national destruction rather than confront the personal loss of face inherent in recognizing that they are not the be-all and end-all of human civilization by any means. This is the most dangerous view of the world imaginable, and a threat that cannot be ignored, deferred to, or resolved by weak and conciliatory appeasement built around fantasies of "peace in our time." That being the case, the presence of nuclear weapons in the arsenal of the free world continues to be not only a prudent and sensible course of action for the foreseeable future but an absolute necessity. Directory: History History -> Developed for the Ontario Curriculum History -> A chronology 1660-1832 The Restoration Settlement History -> History and Social Science Standards of Learning Enhanced Scope and Sequence History -> Evolution of the National Weather Service History -> Chronological documentation for the period through 1842 Copyright Bruce Seymour blio, Cadet Papers of Patrick Craigie History -> History of the 14 History -> History of the ports in Georgia History -> That Broad and Beckoning Highway: The Santa Fe Trail and the Rush for Gold in California and Colorado History -> Capitol Reef National Park List of Fruit and Nut Varieties, Including Heirlooms Prepared for the National Park Service through the Colorado Plateau Cooperative Ecosystems Studies Unit by Kanin Routson and Gary Paul Nabhan, Center for Sustainable Download 182.12 Kb. Share with your friends:
|