The US Navy airship Los Angeles floats above the mooring ship USS Patoka off Panama in 1931. The huge dirigible was perhaps the most salient example of how German military and technical expertise developed during the World War One was incorporated into the American military in the post-war period.
After the end of the Great War, the US was as keen as any of the other victorious Allies to take possession of Germany’s remaining zeppelins. Although obsolete as strategic bombers by 1916, zeppelins were still at the cutting edge of airship technology. The latest X-class, for example, were almost 700ft long and could reach altitudes of 20,000ft. Their six Maybach ‘straight six’ water-cooled piston engines gave them a speed of over 80mph and an endurance of up to 7,500 miles.
Luftschiffbau Zeppelin had been set up by its namesake Ferdinand von Zeppelin in 1908 after a decade of experimentation in rigid airship design. Prior to the Great War, the company had constructed a dozen ‘zeppelin’ prototypes, several of which had gone into commercial service for DELAG, the world’s first airline, carrying over 30,000 passengers on almost 1,600 commercial flights. After being taken under government control in 1914, the company turned to constructing airships for the German army and navy. During the Great War, zeppelins carried out more than 50 bombing raids on the United Kingdom, although they proved to be more effective in reconnaissance activities and North Sea patrols.
Article 202 of The Treaty of Versailles, signed in June 1919, stipulated delivery ‘to the Governments of the Principal Allied and Associated Powers’ of all ‘dirigibles able to take to the air, being manufactured, repaired or assembled’ as part of war reparations. The X-class L72, for example, was given to France in 1920, where she became the ill-fated Dixmunde, while her sister L71 went to Britain along with several other zeppelins of older designs.[1] Unfortunately, the two zeppelins assigned to the Americans were purposely destroyed by their aircrews on 23rd June 1919 in solidarity with the scuttling actions of the German Fleet at Scapa Flo two days earlier. At the time, the US military only operated a small number of C-class ‘blimps’, which were of comparatively limited capability.
In fact, America’s European Allies had already begun constructing their own airships based on zeppelin designs. In October 1917, the French had captured the U-class L49 virtually intact after it had been forced down while returning from a raid on England. In February 1919, the British had started work on the R-38, engineered principally according to L49 specifications. In October of that year, the Americans purchased this airship as a replacement for those sabotaged. However, on August 24th 1921 while still undergoing test flights in England with a British crew, the R-38 crashed. This disaster was followed in February 1922 by the crash of the Roma, an Italian-built semi-dirigible the US had purchased in March 1921. Unperturbed by these setbacks, the Americans proceeded with the construction of their own rigid airship based on the L49. That ship, the Shenandoah, was commissioned in the United States Navy in October 1923.
Shortly after the end of the War, the Zeppelin Company, under the stewardship of Dr Hugo Eckner, had returned to the construction of passenger airships. However, its first two dirigibles were also confiscated by the Allies as war reparations, restricting the company’s commercial activities to the manufacture of aluminium cooking utensils. In 1924, an agreement was reached with the Allied powers for the establishment of a joint venture between the American Goodyear Tire and Rubber Co. and Zeppelin Lufschiffbau to utilize the German company’s patents and technical expertise to construct a new airship for the US Navy. That airship, built at the German company’s headquarters at Friedrichshafen on the northern shore of the Bodensee (Lake Constance), was to become the USS Los Angeles.
Construction of hull ZR-3 began in July 1922 and took over two years. Like earlier zeppelins the Los Angeles was built around a series of transverse ring frames and an internal keel, all of which was of lightweight duralumin metal. The airship’s mostly 24-sided polygonal structure was clearly visible under her outer skin. Her control gondola was directly attached to the forward under-section of the airship, a design practice copied from her German predecessor LZ120 (Bodensee). Propulsion was by means of five Maybach V12 ‘pusher’ engines, which were newly designed for reliability, reduced vibration and fuel economy.
The completed airship’s transatlantic transfer in October 1924 was personally commanded by Eckner. The 4,200 nautical mile journey to the US Naval Station at Lakehurst, New Jersey, took just over 80 hours. After her arrival, her lifting gas was changed from hydrogen to helium, which only the US possessed in sufficient quantities to inflate an airship. Although non-flammable, helium generated less lift than hydrogen, and could not be so blithely jettisoned due to its prohibitive cost. As a result, water from her exhaust gases was recycled to make ballast and help maintain neutral buoyancy as engine fuel was consumed.
In preparation for the airship’s arrival in America, a 160ft mooring tower had been constructed at Lakehurst. This structure, first used in Britain, was not entirely necessary; the Germans had routinely moored their airships directly to the ground; but was regarded as a more efficient system. With its rotating top, a mooring tower allowed the tethered airship to turn in the direction of the wind. The tower at Lakehurst also contained piping through which helium, gas, oil, and water ballast could be pumped aboard. When not moored to the tower, the airship could be stowed alongside the Shenandoah in a 680ft long hanger; then the largest unsupported interior space or ‘room’ in the world. However, as navy vessels, both airships needed to operate away from land; hence the decision to construct a mobile mooring vessel, the USS Patoka.
The Patoka was the lead ship of a class of US Navy oil tankers built towards the end of the War. After her commissioning in November 1919, the Patoka had made several voyages to Europe carrying oil for the US Naval Overseas Transportation Service. Her re-assignment as an airship tender took place in 1924. A mooring mast some 125ft above the water-line was erected towards the tanker’s stern behind her single funnel. After successful mooring trials using the Shenandoah, the Patoka was sent into the mid-Atlantic to assist in the crossing of the Los Angeles from Germany to America, although it does not seem likely her tower was utilized. In 1925, she was due to support the Shenandoah in a proposed polar flight. However, before this could be made, the Shenandoah broke up and crashed during stormy weather, killing fourteen of her crew.
Shenandoah’s loss, like that of the British-built R38, was partly the result of inherent design failings. The L49 zeppelin, on which both were modelled was a military design that maximised altitude by sacrificing weight and thereby strength in its metal skeleton. These failings had been rectified in the design of the Los Angeles, and she was to prove the most resilient and luckiest of all US Navy airships. Nevertheless, even she almost came to grief during a spectacular mooring incident in 1927. On August 25th, while tethered to the tower at Lakehurst a gust of wind lifted her tail. The crew attempted to compensate for this by climbing up the keel towards the stern but prevailing atmospheric conditions continued to push the tail upwards until the airship itself was tilted at 85 degrees from the horizontal. Thankfully, the Los Angeles eventually righted herself with no significant damage or injuries to her crew.
The Los Angeles and the Patoka combined for a series of long-distance flights between 1925 and 1932, destinations including Puerto Rico, Panama, and Florida. In January 1928, the former successfully tethered to the US Navy’s newest aircraft carrier the USS Saratoga. To some extent, these two vessels were rivals. During the War, both Britain and Germany had tested the idea of launching conventional aircraft from airships. The Americans had made similar tests immediately after the War using a Curtiss ‘Jenny’ biplane attached to a C-class blimp. In 1929, the Los Angeles was given her own ‘parasite’ aircraft during trials using an innovative ‘trapeze system’ that could both launch and recapture fighter planes. The tests were so successful the system was adopted for the US Navy’s next generation of airships, the USS Akron and Macon, both being designed with aircraft hangers inside their hulls. However, their severe payload limitations meant that airships were never considered as serious rivals to conventional aircraft carriers.
The Los Angeles and the Saratoga would join forces again in 1931. Both were present during Fleet Action XII, the latest in an annually-held series of US Navy mock battles. Fleet Action XII was designed to test an aviation-heavy fleet’s response to an imaginary invasion of the then US-controlled Panama Canal. It was during these war games that the iconic image of the Los Angeles moored majestically to the tower of the Patoka was taken.
After taking part in Fleet Action XIII the following year, the Los Angeles was decommissioned, evidently in a US Navy cost-cutting exercise. By this time, the USS Akron had taken to the skies, to which the Patoka would become tender during her short career. Despite her state-of-the-art design, the Akron proved an accident-prone airship, and in April 1933 she was destroyed by a storm off America’s east coast. This tragic incident, which cost the lives of 80 crewmen, led to the temporary recommissioning of the Los Angeles for training purposes.
Her career came to a definitive end after the crash of the USS Macon in February 1935. Although America’s helium-filled airships avoided the fiery fate of hydrogen-filled contemporaries such as the R101 and the Hindenburg, they were no less susceptible to hostile weather conditions. The Los Angeles was the only one of the US Navy’s four rigid airships not to suffer a fatal crash; a testament to her German design and manufacture. The airship logged more than 4,200 flying hours during her career and travelled over 172,000 nautical miles. She even ‘acted’ in the movies, playing the fictional ‘USS Pensacola’ in Columbia Picture’s 1931 aeronautical drama Dirigible. She was finally scrapped in 1939, months before the other great survivor of the peacetime airship era, the Graf Zeppelin, was finally broken up.
As for the USS Patoka, her career proved to be as lucky as that of the Los Angeles. After spending half a dozen years in reserve after her service as an airship mooring vessel, she was recommissioned as a seaplane tender in 1939. She had an active though largely uneventful war, operating initially in Brazilian waters and later in the Pacific, where she served as a tender to US minecraft. She was finally broken up in 1948.
[1] Dixmunde was lost with all hands off Sicily on 21st December 1921 due to a mid-air explosion. The British did not commission any of the zeppelins it received as reparations.
Bow Creek to Anatahan 