USS Los Angeles (ZR-3)

The USS Los Angeles was a rigid airship, designated ZR-3, which was built in 1923–1924 by the Zeppelin company in Friedrichshafen, Germany, as war reparation. It was delivered to the United States Navy in October 1924 and after being used mainly for experimental work, particularly in the development of the American parasite fighter program, was decommissioned in 1932.
== Contents ==
 [hide] 
* 1Design
* 2Operational history
* 3Gallery
* 4References
* 5External links
== Design[edit] ==
The second of four vessels to carry the name USS Los Angeles, the airship was built for the United States Navy as a replacement for the Zeppelins that had been assigned to the United States as war reparations following World War I, and had been sabotaged by their crews in 1919.[1] Under the terms of the Treaty of Versailles Luftschiffbau Zeppelin were not permitted to build military airships. In consequence Los Angeles, which had the Zeppelin works number LZ 126, was built as a passenger airship, although the Treaty limitation on the permissible volume was waived, it being agreed that a craft of a size equal to the largest Zeppelin constructed during World War I was permissible.[2]
The airship's hull had 24-sided transverse ring frames for most of its length, changing to an octagonal section at the tail surfaces, and the hull had an internal keel which provided an internal walkway and also contained the accommodation for the crew when off duty. For most of the ship's length the main frames were 32 ft 10 in (10 m) apart, with two secondary frames in each bay. Following the precedent set by LZ 120 Bodensee, crew and passenger accommodation was in a compartment near the front of the airship that was integrated into the hull structure. Each of the five Maybach VL I V12 engines occupied a separate engine car, arranged as four wing cars with the fifth aft on the centerline of the ship. All drove two-bladed pusherpropellers and were capable of running in reverse. Auxiliary power was provided by wind-driven dynamos.[2]
== Operational history[edit] ==
Cover carried on the delivery flight from Germany to Lakehurst, New Jersey, October 12–15, 1924
Airship LZ-126 arriving at Lakehurst, 15 October 1924
Los Angeles (right) and Shenandoah moored in Hangar No. 1 in 1924
Los Angeles was first flown on 27 August 1924, and after completing flight trials began the transatlantic delivery flight on 12 October under the command of Hugo Eckener, arriving at the US Naval Air Station at Lakehurst, New Jersey, after an 81-hour flight of 4,229 nautical miles (7,832 km).[1][3] The airship was commissioned into the US Navy on 25 November 1924 at Anacostia, D.C. with LCDR Maurice R. Pierce in command. On its arrival in the United States, its lifting gas was changed from hydrogen to helium, which reduced payload but improved safety. At the same time the airship was fitted with equipment to recover water from the exhaust gases for use as ballast to compensate for the loss of weight as fuel was consumed, so avoiding the necessity to vent scarce helium to maintain neutral buoyancy.[1]
The airship went on to log a total of 4,398 hours of flight, covering a distance of 172,400 nautical miles (319,300 km). Long-distance flights included return flights to Panama, Costa Rica and Bermuda.[1][4] It served as an observatory and experimental platform, as well as a training ship for other airships.
On 25 August 1927, while the Los Angeles was tethered at the Lakehurst high mast, a gust of wind caught her tail and lifted it into colder, denser air that was just above the airship. This caused the tail to lift higher. The crew on board tried to compensate by climbing up the keeltoward the rising tail, but could not stop the ship from reaching an angle of 85 degrees, before it descended. The ship suffered only slight damage and was able to fly the next day.
In 1929, the Los Angeles was used to test the trapeze system developed by the US Navy to launch and recover fixed wing aircraft from rigid airships. The tests were a success and the later purpose-built Akron-class airships were fitted with this system.[1] The temporary system was removed from the Los Angeles, which never carried any aircraft on operational flights.[5] On 31 January 1930, the Los Angeles also tested the launching of a glider over Lakehurst, New Jersey.[6] [7]
On 25 May 1932, the Los Angeles participated in a demonstration of photophone technology. Floating over the General Electric plant in Schenectady, New York, the crew of the ship engaged in an on-air conversation with a WGY radio announcer using a beam of light.[8]
As the terms under which the Allies permitted the United States to have the Los Angeles restricted its use to commercial and experimental purposes only, when the U.S. Navy wanted to use the airship in a fleet problem in 1931 permission had to be obtained from the Allied Control Commission.[9] The Los Angeles took part in Fleet Problems XII (1931) and XIII (1932), although as was the case with all U.S. Navy rigid airships, demonstrated no particular benefit to the fleet.[10]
The Los Angeles was decommissioned in 1932 as an economy measure, but was recommissioned for a period after the USS Akron crashed in April 1933. Soon returned to storage, the airship was struck off the Navy list in 1939 and dismantled in its hangar, thus ending the career of the Navy's longest serving rigid airship. Unlike the Shenandoah, Akron, and Macon, the Los Angeles' career did not meet a disastrous end.
== Gallery[edit] ==
* 
* The USS Los Angeles in Panama, 1929 
* Passenger cabin of the airship, 1924 
* USS Los Angeles lofted nearly vertical in the 1927 weather-related docking-mast mishap. 
* An RRG Prüfling glider attached to USS Los Angeles for carriage and drop tests. 
* USS Los Angeles anchored to the USS Saratoga. 
* USS Los Angeles over Manhattan, New York, 1930 
* USS Los Angeles in Panama 1929 
* USS Los Angeles in flight 
* USS Los Angeles (ZR-3), USS Patoka (AO-9), USS Lexington (CV-2) off Panama City, Panama, about 1931. From left to right is Pacific Ocean Entrance to the Panama Canal, Isla Flamenco (island), USS Patoka, Isla Perico (island), Fort Amador (just below the airship), Cerro Ancón (hill), USS Lexington, Panama City. 
* US Capitol from the USS Los Angeles 
* USS Los Angeles enters storage hangar for the first time at Naval Air Station, Lakehurst, New Jersey, in 1924