Naval Institute Press, 2009
Reviewed by Mr. John Merrill
William F. Althoff, noted Naval Aviation historian, in his 2009 Naval Institute book tells the almost forgotten history of Lighter than Aircraft (LT A), blimps in the vast antisubmarine warfare effort to defeat marauding U-boats. The growing squadrons of K-type blimps also successfully addressed other demands of the World War II years. Hopefully, this article will provoke further interest in Althoff s contribution to the LT A history.
In his Preface, the author states, “What deserves examination are the naval, political, and technological environments in which the platform had to operate in the decade from 1935 to 1945 … ” His findings are remarkably thorough and presented interestingly. It is his attention to the context of every aspect of the LT A’s role in the war effort that provides a sense of completeness and clarity to the aircraft’s wartime history. This allows the reader to be part of the ongoing day-to-day LT A activities and to be aware of how the LT As became part of the growing Navy’s growing anti-U-boat efforts.
The LTA WWII history can also stand alone as an exemplary case study of how a Navy program grew and the breadth of its accomplishments. This is in spite of the fact that even though not much liked, LT As had to grow and fit in under the duress of wartime while simultaneously addressing training, growth, manpower needs and a rapidly expanding geographic sphere of operation. The historical, operational and political aspects are made clear. The eventual decline of the LTA makes the book’s recognition of the wartime contribution timely as the details of non-rigid aircraft and their history are dimming.
The author carefully details the history and high value of the United States Navy non-rigid aircraft (blimp) to our siege and success in antisubmarine warfare against the German U-boat in the period 1941 to 1945. Althoff brings his extensive research on U.S. Naval Aviation and technology to this story of one of the unsung heroes of WWII.
Introduction End and Beginning
Chapter 1 Technical Decisions and High Consequences
Chapter 2 Preparations
Chapter 3 Bitter Spring
Chapter 4 Turning Tide
Chapter 5 Southern Squadrons
Chapter 6 Mediterranean Squadrons
Chapter 7 Pacific Coast Operations and Atlantic Finale
Chapter 8 The Performance
Some military systems are endowed with high visibility and long-term interest from inception, during their use, and even years later when they have been overtaken by new or more exotic technology. This is true of many of the Navy systems.
However, this is not true for LT As. As one reviewer of this book noted, “Forgotten Weapon” fills an important void in World War II history.” 1 Today many do not know the part the blimp played in the Battle of the Atlantic during WWII. Althoff provides insight about the contributions of the blimp squadrons not only in the Atlantic but also in other oceans and seas.
An article “The Forgotten Blimps of World War II” addresses remembering blimps with the comment “LT A blimp squadrons continued in the U.S. Navy after World War U at an ever decreasing level until the 1960s when they faded from the scene.” Another writer entitled his observation about the loss of interest in airships “LTA and WWII: role of Navy airships often forgotten.” In the war, blimps escorted convoys along the coasts and well out to sea, as far as 2000 miles.
The first two chapters provide a broad historical review of relevant interwar national and international developments, including the Navy’s interest in rigid and non-rigid airships.
The end of the 1930s saw rigid lighter-than-air aircraft removed from Navy planning and blimps (non-rigid) with a fading priority for naval warfare. Flying boats (PBYs) and aircraft carriers were in the ascendancy. The unit cost per PBY approximated the cost of a typical K type LT A without considering the additional extensive ground needs of blimps. In addition, “by 1940 most persons holding responsible positions within the Naval establishment or in other organs of the government viewed airships with skepticism if not contempt; some indeed, were openly vindictive.” While the LT A role in escort and shipping control was recognized, new LTA construction was deemed non urgent, and the construction of two blimps was projected for the 1938 Navy budget.
As the decade ended, the status of LT As could only be described as at a very low point and perhaps close to obscurity. However, the huge success of the U-boat in 1939 and 1940 brought significant effort to the development of new or improved submarine detection antisubmarine equipment to lessen the impact of the German submarines soon at work along the whole east coast of the United States.
LTA’s Participation begins
During the first week of WWII in September 1939, President Roosevelt, under neutrality considerations and a limited national emergency, directed the Navy to organize a neutrality patrol to extend sea control over the western Atlantic: “… the CNO ordered the commander of the Atlantic Squadron to establish combined air
and surface reconnaissance-that is, reporting and tracking any air, surface, or submarine units of belligerent powers in the nation’s sea approaches.” “Within weeks, New York, and Philadelphia newspapers had added the Navy’s blimps to active patrol forces.”
The blimps with long range, speed, endurance, night and inclement weather capability would prove valuable for antisubmarine warfare (ASW) and convoy escort patrols. Initially, blimps were limited by small numbers and were not war ready. Lack of clarity regarding Army/Navy responsibility over water air cover during wartime clouded some issues, and time was lost.
Lakehurst Naval Air Station in New Jersey, the Navy’s only airship facility, was close to moribund with regard to manpower and equipment at the time of Pearl Harbor. However, it grew and became the center of LT A activity for the war years. For seven months (December 1939-June 1940) Lakehurst LTAs conducted at-sea exercises with submarines from Submarine Squadron Two at New London. In June, the results provided to the Chief of Naval Operations included various blimp missions: search and rescue exercises, marker buoy tests, airship assist in torpedo recovery, mine spotting, depth charging, bombing, aerial photographic and observation exercises. Blimp sightings included surfaced and submerged submarines.
Through all the war years this utility aspect of blimps brought ever widening attention and a continually growing list of ways for the blimp with its unique qualifications to meet new operational needs. Blimp utility now included downed aircraft, disabled vessels, and drifting survivors in addition to the above list. This resulted in the establishment in January 1944 of ZJ-1 Airship Utility squadron to relieve Fleet Squadrons of utility assignments that were incessantly growing.
From this minimal start up in December 1941 with 16 of all types of blimps and very limited personnel, the LT A numbers of blimps and personnel would grow during the war years ahead. In January 1945, there were 141 blimps on hand and 7500 personnel. The book reveals the rapid growth and enormous challenges of training and setting up of blimp squadrons and fitting in of LTA’s main impact as part of convoy escorting with the growing antisubmarine effort.
The small number of blimps then available at the Navy’s Lakehurst facility also found use as test platforms for new submarine detection equipment currently in the research and development phase. The blimps provided candidate platforms for experimentation and later use of the new equipment. The book is the story of LTAs adjusting to its new role in antisubmarine warfare and with the development of new high technology systems. The number of LTAs grew from 10 pre-War to the 141 cited above when the War ended.
Work associated with the blimps adapted to a new role in antisubmarine warfare (ASW) by training crews for their operation, establishing 15 squadrons and facilities in the United States and overseas, and lastly (and most important) fitting in with overall antisubmarine convoy escorting tasks with airplanes (Navy and Army) and surface ships participating. These are some of the areas the book brings to light which are carefully examined in the book. All this growth of the LT As occurred under the pressure of the unending wartime emergency.
The reader is carried along in this large book (8.5 x 11.5 inches) with an extensive forty-five pages of chapter endnotes attributing where appropriate and providing pathways to further knowledge about the subject or topic. The large format also provides space for 30 carefully selected and edited photographs, some full pages, which provide further realism to the historical account.
Aggressive ASW tools: Radar, MAD, Sonobuoy, Loran
Perhaps unexpectedly, the blimp became one of the platforms for several significant high technology innovations for detecting submarines with important blimp involvement in the development and later as a user. MAD (magnetic airborne detection), the sonobuoy and Long Range Navigation (LORAN) are addressed. The blimp, as a test platform and then user of the operational devices, assisted the evolution of these important submarine detectors from earliest laboratory models to production. Today, sonobuoys are the principal airborne submarine detector.
In the evolution of these wartime systems, the value of the coming together of the civilian scientists and naval aviators in the research and development is cited. During WWII, Vannevar Bush, head of the National Defense Research Committee (NDRC), inaugurated a successful policy for war-related scientific research under contracts to civilian universities and institutions. It developed new effective relationships among American universities, government and armed forces. The Committee’s interest included improvement of the reliability and effectiveness of present equipment. The origin, evolution and integration of these new tools, important to the LT A’S role as part of the convoy process, are discussed in detail.
In addition, the blimp had a role in radar development and operational use on the blimp along with the adoption of radar by airplanes. In addition to the human eye, radar with day and night capability provided submarine searching-capability. Once detected, MAD supplied submarine tracking and the sonobuoy underwater submarine tracking.
As example of blimp early participation, the testing of a new submarine detection equipment from Columbia University’s New London NDRC Underwater Sound Laboratory March 7, 1942 brought the Lakehurst blimp K-5 cruising over waters south of New London using a new device, sonobuoy, to detect the submarine S-20, then running completely submerged. The buoy was able to receive underwater sounds from the submarine via the radio link to ranges of several miles. “By the fall of 1943, however, these buoys would be effective, invaluable, and famed, their production pushed to supply the demand.” Today, sonobuoys are the principal airborne submarine detector.
Convoys coupled with these systems (also useful to airplanes), and additional other peripheral assistance including air dropped weapons on the blimps created a U-boat wariness that caused Donitz to eventually withdraw his submarines from the western Atlantic areas.
Throughout the book, the author frequently quotes Admiral Karl Donilz, German U·boat Commander in Chief. This use of a contrasting viewpoint, comment or assessment of an ongoing Allied ASW technique or methodology helps to provide balanced perspective.
The blimp also had a role in the rapid wartime development of Loran (long range navigation) that allows a vessel or aircraft to determine its position in all weathers and at great distances from shore. On June 13, 1942, engineer John A. Pierce, of Harvard and MIT Radiation Laboratory, conducted the first demonstration of the Loran navigation system aboard the Lakehurst K-2 during a 250-mile flight from Lakehurst to Ocean City, Maryland and return. This system went from being a concept in October 1940 to operational status by mid· 1942 and almost universal use by the Allies at the end of the war.
This comment about new systems evolving is to point out the inclusiveness by Althoff during his examination of the blimp’s wartime role in the ultimate defeat of the U-boat beginning in mid-1943.
The low point in the ASW effort against the U-boats is described in Chapter 3, Bitter Spring. A summary of ship sinkings at the end of 1942, tallies a total loss of ships sunk by U-boats at 1,161, accounting for 76% of all ships sunk that year. Turning Tide, Chapter 4, marked the upswing in ASW success in May that continued until the end of WWII.
Blimps as an effective part of the ASW effort were beginning to be recognized during this difficult year. In April 1942, Secretary of the Navy Frank Knox in the naval plane authorization program increased the number of LT As from 48 to 72.
Early blimp recognition by Admiral Karl Donitz in August 1942 is appropriate. “When queried as to America’s ‘dwarf dirigibles,’ Donitz replied; ‘In contradiction to a wide-spread belief, I should like to emphasize that operations in American waters are by no means a simple matter. It cannot be denied that even the ‘blimps’ have a certain effectiveness in defense, and the Americans have known how to organize very rapidly a defense that commands respect.”
Balancing: Bitter Spring and Tide Turning
Althoff addresses the challenges of the extensive and seeming unending U-boat successes in 1942 costing more than two merchant ships per day during February to March. The loss of lives, ships, and material compounded problems. The early U-boat assault Operation Drumbeat probed almost with impunity the coastal shores from the St. Lawrence to Cape Hatteras as well as penetrating into the Gulf of Mexico not far from New Orleans. This grim year of 1942 became a period of building, waiting, developing new ASW weapons, organizing and focusing. This was the period of preparation to counter the lack of preparedness to protect merchant vessels from the U-boats. Results of these actions were not immediately predictive of the turned tide and successful ASW that began in May 1943.
A coming together
The unexpected reversal of the U-boat’s nearly four years of success in the Atlantic Ocean and coastal North America was an end result of the coming together of the creation and fielding of the needed resources, introduction of advanced ASW weapons and overall systems use optimization resulting from significant broad application of operations research to ASW. England’s several years of successful experience with the application of operations research to the submarine problem provided enhanced understanding of convoy escort and air cover needs which contributed to Donitz’s late 1943 gradual withdrawal of U-boats from the Atlantic sector. Further, a meeting of the Allied leaders Churchill and Roosevelt in Casablanca during early 1943 ended with a fresh and firm resolve, as a first priority, to counter the U-boats more aggressively.
September 1939-April 1943 (44 months) 193
May-June-July 1943 100
The means for this implementation of operations research was the U.S. Antisubmarine Warfare Operations Research (ASWORG) established in early 1942 in support of Admiral King’s antisubmarine efforts. The work of the ASWORG, including the collection, analysis and systematic study of ASW, successfully brought science trained civilians and Navy and Army operations officers to address the problems. In some instances positive results were almost immediate. The late May 1943 establishment of Admiral King’s Tenth Fleet with defined responsibility for antisubmarine operations sea and air further stimulated this cohesive overall effort.
Beginning in early 1942 through the years ahead, the roles of the LTA in the War effort never stopped growing. Blimp utility soon included torpedo chasing and recovery, aerial observation, photography, radio direction finding calibration flights, radar calibration, sonobuoy training, radar operator training, locating downed aircraft and disabled vessels, drifting survivors, ship’s camouflage and submarine operations. Further, the blimp’s usefulness on convoy escort, especially on night patrol and under conditions of poor visibility, was recognized.
The Squadrons: U.S., Caribbean, Brazil, Mediterranean and elsewhere
Details of the squadrons, their formation, their locations and operations permeate this story of the LTAs. The author has left no stone unturned to provide the reader with the utmost detail for each squadron and its participants.
The book’s Appendix E Statistical Summmy: U.S. Fleet Airship Operation. 1942-45 with a few numbers reflects the hardeamed squadron month-by-month growth, implementation, and results of the 15 squadrons. In various chapters, the reason, purpose and origin of each squadron is told. Squadron commissioning, the adjustment to the geographical location, the particular operations, living conditions, and in some instances the gradual reduction in squadron numbers as the war begins to move along more favorably for the Allies is detailed.
Several chapters devoted to squadron development and broad geographical deployment, the important role of the LTA and the demands on those involved are highlighted. As mentioned previously, Althoff provides rich context explaining why the various squadrons came about and answered particular needs of new geographical areas. As U-boats moved to different geographical areas, the LTA squadrons followed suit.
Lakehurst, the Navy’s sole operating/experimental base for airships in operation since 1921, with a very limited airship complement but a core of competent ainnen, provided training and classes for officers, cadets and enlisted men. Befitting personnel had to be found, as well as a hundred or more K-type blimps which had to be manufactured by Goodyear, debugged, and adapted for the ASW and escort patrols. This was all preparation. The establishment and participation of the 15 Airship Squadrons in the ongoing heavy participation in ASW for the four years 1942-45 confinns the importance of remembering LTA.
Merchant marine ship convoy escorts present a group of somewhat disparate members that have to work in coordinated fashion while facing the uncertainties of the oceans and the weather and the enemy. Blimps, destroyers, airplanes and independent merchant ships working together in an escort environment provide many challenges.
Growing LTA support in 1942 saw the dedication and operation of six blimp squadrons four: on the east coast (South
Weymouth, Massachusetts, Lakehurst, New Jersey, Weeksville, North Carolina, Glynco, Georgia) and three on the west coast (Santa Ana, Moffett Field in California and Tillamook, Oregon).
To accommodate the existing and forthcoming squadrons, the construction began on seventeen blimp hangars ( 1000 feet long) to accommodate the dozens of blimps.
Brazil being at war with the Axis in mid-August 1942 brought increased U-boat activity in the south Atlantic. In 1943, three LTA squadrons were established with multiple detachments to cover the 1800-mile northeast and east coasts of Brazil. Beyond continental United States, the LTAs were needed and sent to locations in Panama, Trinidad, Gibraltar, and Morocco. Detailed consideration of the locations and operations of each of the 15 squadrons is given attention by Althoff.
VE Day in Europe found US Navy Airships in north, central and South America, southern Europe and northwest Africa. The following year, 1946, the LTA squadrons were reduced from 15 to 2; bringing the overall standing within the Navy of LTAs then nearly back to its indeterminate status of 1940.
Statistical Summary data from Appendix E Statistical Summary provide a measure of the LT A contribution to convoying against the U-boat. A picture caption in the book regarding the sinking of SS Persephone by a U-boat is appropriate. “SS Persephone, 25 May 1942. Bound for New York, the tanker took two ‘fish’ from U-593- probably the only vessel torpedoed while under LT A escort in two world wars.”
With more than eighty thousand ships escorted in WWII, alone this is a remarkable comment about the effectiveness of LTA escorting.
Ships Escorted, Yearly
Aviation historian Althoff’s LT A history meets all the right criteria for scale, scope, clarity, and thoroughness. Attention to relevant actions in the world around the challenged LTA is not overlooked and surprisingly helps to make the history an interesting and satisfying read. As previously mentioned, the wonderful and mostly large and significant number of photographs gives the reader a kind of “this is happening now” feeling. The forty-five pages of endnotes provide not only attribution but also paths to further knowledge. The eight appendices are more than a scholarly adjunct to the book. This history from the perspective of the LTA provides another window on the vast WWII.