Beginning in 1908 and ending in 1937, the U.S. Army established a program to operate airships. With the exceptions of the Italian-built Roma and the Goodyear RS-1 , which were both semi-rigid, all Army airships were non-rigid blimps. These airships were used primarily for search and patrol operations in support of coastal fortifications and border patrol. During the 1920s, the Army operated many more blimps than the U.S. Navy. Blimps were selected by the Army because they were not seen as "threats" on the battlefield by opposing forces, unlike airplanes, due to their passive role in combat. [1]
The history of American military aviation began during the Civil War, when the Union Army operated observation balloons. [2] Later, a balloon was used by the US Army in Cuba during the Spanish–American War. These were ad hoc and not part of an established branch of the Army. The use of observation balloons continued after the end of World War I. The last use of observation balloons by the Army was during maneuvers conducted in Louisiana during September 1941. [3] Balloons must either be tethered, or go where they are blown by the wind, but towards the end of the nineteenth century powered airships, capable of being directed at the will of the pilot, were developed.
In 1908, the US Army experimented with its first powered aircraft, the SC-1, or Signal Corps number 1. [4] It was a small non-rigid airship with a top speed under 20 mph and an endurance of just over 2 hours. Following tests at Fort Myer, the SC-1 was sent to Fort Omaha, Nebraska, where the Signal Corps School was located. While the SC-1 was being tested at Fort Myer, the Signal Corps had built an airship hangar and a plant to produce hydrogen gas at Fort Omaha. Fort Omaha became, for a while, the first permanent military airfield in the United States. The SC-1 was scrapped in 1912, and the base at Fort Omaha closed in 1913. [5]
The US Army operated French observation balloons during World War I, but did not operate another airship until after the war ended. During World War I the Joint Airship Board assigned the US Navy the role of acquiring and developing rigid airships. This did not dissuade the Army from pursuing its own course. Colonel William Hensley flew as an observer on the return voyage of the British R34 airship from Long Island, New York to the UK in the summer of 1919. Hensley was then sent on a confidential mission to contact the Zeppelin Company to attempt to purchase the remaining undelivered wartime Zeppelin, the L 72. The scheme probably originated with General "Billy" Mitchell. [6] Hensley visited the Zeppelin plant, inspected L 72 and flew on the Bodensee, a small passenger Zeppelin. The Inter-Allied Commission of Control ordered that L 72 should be turned over to France. In November 1919 the US Army contracted with the Zeppelin corporation for construction of the LZ 125, which was to be larger than the R38 class airship which the USN had contracted to purchase from Britain as the ZR-2. This attempt to avoid the conditions set by the Joint Airship Board would have encountered legal problems as the US Senate refused to ratify the Allied Peace Treaty with Germany until October 1921. [7] Complaints by the Secretary of the Navy resulted in the Secretary of War ordering the German contract terminated in December 1919. [8] [9]
Following the end of World War I, the U.S. Army acquired a variety of blimps from US, French and British sources. Plans were made for operating airships from both Fort Bliss and Brooks Field, in Texas [10] and Langley Field, Virginia. The first blimp operated by the Army was the A-4, which was operated primarily from Langley until transferred to the new Balloon and Airship School at Scott Field, Illinois. The Army operated several Navy C class blimps and D class blimps during the immediate post-World War I era. [11]
Army blimps participated in the "Mitchell" bombing test in 1921. They were used for training, coastal patrol, and experimentation in the early 1920s. The Army purchased three British SST class blimps from the British, which were operated out of Biggs Field, Fort Bliss, and Brooks Field, both in Texas for purposes of border patrol between 1920 and 1923. [12]
During the 1920s the Army developed several "Motorized Observation Balloons". The OB-1 and MB were intended to fly to where needed, and then be tethered as observation balloons. [13] [14]
The US Army acquired the Italian semi-rigid airship Roma in 1921. The Roma was the largest airship ever operated by the Army and was based at Langley Field. With a cruising speed of 50 mph and a range of 7,000 miles, the Roma allowed the Army to consider transcontinental deployments, missions to Panama, the fast transport of cargo and passengers, and long-range sea patrols. The Roma crashed into high-tension wires and was destroyed by fire near Norfolk, Virginia on 21 February 1922. The Roma tragedy led Congress to decree that all future US airships would use non-flammable helium instead of hydrogen as the lifting gas. [15] [16]
During the 1920s and '30s, the US Army Airship Service was responsible for improvements in airship operation construction. These included the use of internal gondola suspension [17] and the only advanced semi-rigid airship manufactured in America, the RS-1, built by Goodyear. [18] The army operated the RS-1 during the late 1920s until the requirement for a new envelope grounded the ship and resulted in it being scrapped in 1930. [19] The Airship Service also supplied airship pilots and logistic support for stratospheric research flights. [20]
The majority of the airships operated by the US Army during the 1920s and '30s were of the "TC" Class, designed for coastal patrol duty, [21] because the US Army had long held the primary responsibility for coastal and harbor defense of the US. [22] The airship was seen as capable of searching for hostile ships and tracking those ships until they could be engaged by coastal defenses or Army bombers. [21] One TC class blimp, the C-41, was often used for various public relation experiments in the 1930s, including landing on the Washington D.C. mall to lay a wreath at the Lincoln Memorial [23] and experimented with picking up mail from a moving train. [24]
Amongst the most interesting U.S. Army Airship Service experiments was to pursue the ability to operate airplanes from airships. While both the Germans and British had experimented with releasing fighters from rigid airships, it was the US Army that first flew an airplane from the ground and 'hooked' on to a trapeze suspended from an airship. Many tests involving a Sperry Messenger airplane and TC-3, a TC class blimp, were made in the mid-1920s. Eventually, the technology was assumed by the US Navy on the "flying aircraft carriers", USS Akron (ZRS-4) and USS Macon (ZRS-5). [25]
The US Army continued to show interest in the acquisition and operation of rigid airships well into the 1930s. [26] [27] The Army Airship Service developed new designs, and operated a number of blimps, primarily from Scott Field and Langley Field through the early 1930s when competition for funding from the rapidly growing Air Corps started its decline. In 1932, the Army contracted for two blimps significantly more capable than any in service, these were the TC-13 and TC-14. When Army Airship operations were terminated in 1937, a number of Army blimps were transferred to the US Navy, but only two, the TC-13 and 14 were ever operated by the Navy. [28]
Unlike the Navy, the Army had failed during the post-World War I era to establish a definite mission, much less a comprehensive plan for accomplishing that mission, for its airships. By 1935, Congress was considering the elimination of funding for the Army airship program, and Chief of the Air Corps Major General Benjamin Foulois, who himself had been a pilot of the SC-1, was recommending the program be terminated. In mid-1937, the US Army's airship operations were officially ended.
As Congress refused to authorize further expenditures for Army airships but did allow funding of observation balloons, the army resurrected the "Motorized Observation Balloon" concept abandoned in the 1920s. [29] The "Motorized Observation Balloon" continued in use for several more years. [30] There were even new 'pony blimps' constructed. [31] These were the five C-6, seven C-8 and four C-9 class airships. [32] Two of the TE-3 class were re-designated C-7s. The last US Army airships were the two C-7s which were transferred to the Navy in 1943. [33]
Following World War II, the War Assets Administration put up for sale sixteen Motorized Observation Balloons of the C-6, 8 & 9 classes. One was briefly operated by the Douglas Leigh Sky Advertising Company between 1948 and 1950, the C-6-36-11 made its last flight on 14 June 1950. [34]
The K-class blimp was a class of blimps built by the Goodyear Aircraft Company of Akron, Ohio for the United States Navy. These blimps were powered by two Pratt & Whitney Wasp nine-cylinder radial air-cooled engines, each mounted on twin-strut outriggers, one per side of the control car that hung under the envelope. Before and during World War II, 134 K-class blimps were built and configured for patrol and anti-submarine warfare operations, and were extensively used in the Navy’s anti-submarine efforts in the Atlantic and Pacific Ocean areas.
The G-Class Blimps were a series of non-rigid airships (blimps) used by the United States Navy. In 1935, instead of developing a new design airship, the Navy purchased the Goodyear Blimp Defender for use as a trainer and utility airship assigning it the designator G-1. Defender was built by the Goodyear Aircraft Company of Akron, Ohio and was the largest blimp in the company’s fleet of airships that were used for advertising and as passenger airships. Goodyear built additional G-class airships for the Navy during World War II to support training needs.
The L-class blimps were training airships operated by the United States Navy during World War II. In the mid-1930s, the Goodyear Aircraft Company built a family of small non-rigid airships that the company used for advertising the Goodyear name. In 1937 the United States Navy awarded a contract for two different airships, K-class blimp designated K-2 and a smaller blimp based upon Goodyear's smaller commercial model airship used for advertising and passenger carrying. The smaller blimp was designated by the Navy as L-1. It was delivered in April 1938 and operated from the Navy's lighter-than-air facility at Lakehurst, New Jersey. In the meantime, the Navy ordered two more L-Class blimps, the L-2 and L-3, on September 25, 1940. These were delivered in 1941. L-2 was lost in a nighttime mid-air collision with the G-1 on June 8, 1942.
The J-class blimps were non-rigid airships designed by the Navy Bureau of Aeronautics and Goodyear Tire & Rubber Company in the early 1920s for the US Navy.
The Goodyear Aircraft Company of Akron, Ohio built the M-class blimp for the US Navy as the follow-on to the K-class anti-submarine warfare blimp used during World War II. It was a significantly larger airship, 50% larger than its predecessor. Four airships, designated M-1 through M-4, were delivered in early 1944. Operations of K-ships in tropical regions had shown a need for a blimp with greater volume to offset the loss of lift due to high ambient temperatures.
The SSZ non-rigid airships or "blimps" were developed in United Kingdom during World War I from the earlier SS class. The main role of these craft was to escort convoys and scout or search for German U-boats. A secondary purpose was to detect and destroy mines.
The SCDA O-1 was an Italian semi-rigid airship, the only true semi-rigid airship to serve with the United States Navy.
The DN-1 was the United States Navy's first airship.
The B class blimps were patrol airships operated by the United States Navy during and shortly after World War I. The Navy had learned a great deal from the DN-1 fiasco. The result was the very successful B-type airships. Dr. Jerome Hunsaker was asked to develop a theory of airship design, Lt. John H. Towers had returned from Europe having inspected British designs, and using reports from attachés on British airship operations, the Navy was prepared to seek bids for blimps from American manufacturers. On 4 February 1917 the Secretary of the Navy directed that 16 nonrigid airships of Class B be procured. A February 12, 1917 meeting with the Chief of the Bureau of Construction and Repair, and representatives of Goodyear, Goodrich, Connecticut Aircraft Company, Curtiss Aeroplane and Motor Corporation, and U.S. Rubber Company, it was agreed that the order for 16 dirigibles was beyond the capability of any one company. The conference resulted in a committee to coordinate on sharing raw materials, information and experience. Ultimately Goodyear manufactured 9 envelopes, Goodrich made 5 and Curtiss assembled the gondolas for all of those 14 ships. Connecticut Aircraft contracted with U.S. Rubber for its two envelopes and with Pigeon Fraser for its gondolas. The Curtiss-built gondolas used by Goodyear and Goodrich used modified Curtiss JN-4 fuselages powered by Curtiss OXX engines. The Connecticut Aircraft blimps were powered by Hall-Scott engines. One ship, B-20 was equipped with a special control car. All B-Class airships were delivered to the Navy between August 1917 (B-1) and September 1918 (B-20).
The C-class blimp was a patrol airship developed by the US Navy near the end of World War I, a systematic improvement upon the B-type which was suitable for training, but of limited value for patrol work. Larger than the B-class, the C-class blimps had two motors and a longer endurance. As with the B-class, the envelope production was split between Goodyear and Goodrich, with control cars being built by the Burgess division of Curtiss Aeroplane and Motor Company. Originally the Navy ordered 30 but reduced the number to 10 after the armistice in November 1918. All ten of the "C" type airships were delivered in late 1918, and examples served at all of the Navy's airship stations from 1918 to 1922. In 1921, the C-7 was the first airship ever to be inflated with helium. The Navy decommissioned its last two remaining C-type blimps, the C-7 and C-9 in 1922.
The D class blimp was a patrol airship used by the US Navy in the early 1920s. The D-type blimps were slightly larger than the C-type and had many detail improvements. The Navy continued the practice of dividing the envelope production between Goodyear and Goodrich. The control cars were manufactured by the Naval Aircraft Factory. The major improvements over the C-type blimps were a better control car design and easier, more reliable controls and instrumentation. The engines were moved to the rear to reduce noise and allow easier communications between crew members. The fuel tanks were suspended from the sides of the envelope. The envelope was identical to the C-type, except an additional six-foot panel was inserted for a total length of 198 feet (60 m) and a volume of 190,000 cubic feet (5,400 m3). The last of the D-Class, D-6, had a redesigned control car by Leroy Grumman who later founded the Grumman Aircraft Engineering Corporation.
The E class of US Navy blimps comprised a single airship, built during World War I by Goodyear as one of a group of three small blimps offered to the US government. Two were purchased for the US Navy and one for the US Army. The Navy blimps were designated E-1, F-1, and the Army airship A-1. These airships had identical envelopes but different cars. The E-1 was delivered to Pensacola, Florida in December 1918. It was flown only at Pensacola serving as a trainer at the Airship School. A new envelope was provided in December 1920. E-1 was retired from service sometime in 1924.
The F class of US Navy blimps comprised a single airship, built during World War I by Goodyear as one of a group of three small blimps offered to the US government. Two were purchased for the US Navy and one for the US Army. The Navy blimps were designated E-1, F-1, and the Army airship A-1. Classified as an "Experimental Engine Testing Dirigible." F-1 had the same envelope size as the E-1, due to the use of a tractor mounted 125 hp Union engine, the performance was different. F-1 spent its entire career at Hampton Roads. It was flown in both tractor and pusher configurations. It also may have been flown with a Curtiss OXX engine. F-1 was removed from inventory in November 1923.
The H class blimp was an observation airship built for the U.S. Navy in the early 1920s. The original "H" Class design of 1919 was for a twin engined airship of approximately 80,000 cubic feet volume. Commander Lewis Maxfield suggested that a small airship which could be used either as a tethered kite balloon, or be towed by a ship until releasing its cable, would be able to scout on its own. The concept was an airship similar to the later Army Motorized Kite Balloons.
The K-1 was an experimental blimp designed by the United States Navy in 1929. The K-1 was not the prototype of the later K-class blimps.
Records concerning the history of French airships in US Navy service are fragmentary. A number of airships of various classes were operated by the US Navy (USN) during World War I from the French Naval Base at Paimbœuf, which was designated a US Navy Air Station from 1 March 1918 onward. It appears that at least 13 French manufactured airships were operated by the USN from Paimbœuf; six were eventually shipped to the United States and one was returned to France before the armistice. The Navy operated or ordered four Astra-Torres type airships, one T-2—the Captain Caussin, two CM types, and three or four VZ types.
The SST class of non-rigid airship or "blimp" was developed in Great Britain during World War I from the earlier SS class airship. The main role of these craft was to escort convoys and scout or search for German U-boats. A secondary purpose was to detect and destroy mines.
The British NSclass non-rigid airships were the largest and last in a succession of "blimps" that served with the Royal Naval Air Service during World War I; developed from experiences gained with earlier classes to operate off the east coast of Britain on long-range patrols. Despite early problems, examples of the class went on to break all flying records for non-rigid airships, and the type became regarded as the most efficient of its kind.
C-5 was a C class blimp operated by the U.S. Navy in 1918 and 1919. It was one of ten C class hydrogen inflated non-rigid airships constructed by Goodyear and Goodrich primarily for naval patrol duty and training during World War I.