https://en.wikipedia.org/wiki/USS_Shenandoah_(ZR-1)
USS Shenandoah was the first of four United States Navy rigid airships. It was
September 1923. It developed the U.S. Navy's experience with rigid airships, and
made the first crossing of North America by airship. On the 57th flight,
Shenandoah was destroyed in a squall line over Ohio in September 1925.
Shenandoah was originally designated FA-1, for "Fleet Airship Number One" but
this was changed to ZR-1. The airship was 680 ft (207.26 m) long and weighed 36
tons (32658 kg). It had a range of 5,000 mi (4,300 nmi; 8,000 km), and could
reach speeds of 70 mph (61 kn; 110 km/h). Shenandoah was assembled at Naval Air
large enough to accommodate the ship; its parts were fabricated at the Naval
Aircraft Factory in Philadelphia. NAS Lakehurst had served as a base for Navy
blimps for some time, but Shenandoah was the first rigid airship to join the
fleet.
The design was based on Zeppelin bomber L-49 (LZ-96), built in 1917. L-49 was a
lightened Type U "height climber", designed for altitude at the expense of other
qualities. The design was found insufficient and a number of the features of
newer Zeppelins were used, as well as some structural improvements. The
structure was built from a new alloy of aluminum and copper known as duralumin.
Girders were fabricated at the Naval Aircraft Factory. Whether the changes
introduced into the original design of L-49 played a part in Shenandoah's later
breakup is a matter of debate. An outer cover of high-quality cotton cloth was
sewn, laced or taped to the duralumin frame and painted with aluminum dope.
The gas cells were made of goldbeater's skins, one of the most gas-impervious
materials known at the time. Named for their use in beating and separating gold
leaf, goldbeater's skins were made from the outer membrane of the large
intestines of cattle. The membranes were washed and scraped to remove fat and
dirt, and then placed in a solution of water and glycerine in preparation for
application to the rubberized cotton fabric providing the strength of the gas
cells. The membranes were wrung out by hand to remove the water-glycerine
storage solution and then rubber-cemented to the cotton fabric and finally given
a light coat of varnish. The 20 gas cells within the airframe were filled to
about 85% of capacity at normal barometric pressure. Each gas cell had a
spring-loaded relief valve and manual valves operated from the control car.
Name: USS Shenandoah
Namesake: Shenandoah Valley
Ordered: 11 July 1919
Builder: Naval Aircraft Factory, Philadelphia
Hangar No. 1, NAS Lakehurst
Laid down: 24 June 1922
Launched: 20 August 1923
Christened: 10 October 1923
Commissioned: 10 October 1923
Maiden voyage: 4 September 1923
Struck: 5 September 1925
Honors and
awards: First transcontinental U.S. flight
Fate: Crashed during storm near Caldwell, Ohio, 3 September 1925
Notes: First rigid airship commissioned into U.S. Navy
world's first helium-filled rigid airship
On 2 September 1925, Shenandoah departed Lakehurst on a promotional flight to
the Midwest that would include flyovers of 40 cities and visits to state fairs.
Testing of a new mooring mast at Dearborn, Michigan, was included in the
schedule. While passing through an area of thunderstorms and turbulence over
Ohio early in the morning of 3 September, during its 57th flight, the airship
was caught in a violent updraft that carried it beyond the pressure limits of
its gas bags. It was torn apart in the turbulence and crashed in several pieces
near Caldwell, Ohio. Fourteen crew members, including Commander Zachary
Lansdowne, were killed. This included every member of the crew of the control
car (except for Lieutenant Anderson, who escaped before it detached and fell
from the ship); two men who fell through holes in the hull; and several
mechanics who fell with the engines. There were twenty-nine survivors, who
succeeded in riding three sections of the airship to earth. The largest group
was eighteen men who made it out of the stern after it rolled into a valley.
Four others survived a crash landing of the central section. The remaining seven
were in the bow section which Commander (later Vice Admiral) Charles E.
Rosendahl managed to navigate as a free balloon. In this group was Anderson
The crash site attracted thousands of visitors in its first few days. Within
five hours of the crash more than a thousand people had arrived to strip the
hulk of anything they could carry. On Saturday, 5 September 1925, the St.
Petersburg Times of Florida reported that the site of the crash had quickly been
looted by locals, describing the frame as being "[laid] carrion to the whims of
souvenir seekers". Among the items believed to have been taken were the vessel's
logbook and its barograph, both of which were considered critical to
understanding how the crash had happened. Also looted were many of the ship's 20
deflated silken gas cells, each worth several thousand dollars, most of them
unbroken but ripped from the framework before the arrival of armed military
personnel. Looting was so extensive that it was initially believed even the
bodies of the dead had been stripped of their personal effects, and that
operatives from the Department of Justice were being sent to investigate. That
this was happening was soon denied by those publicly involved in the incident,
however. Still, a local farmer on whose property part of the vessel's wreckage
lay began charging the throngs of visitors to enter the crash site at a rate of
Official inquiry brought to light the fact that the fatal flight had been made
under protest by Commander Lansdowne (a native of Greenville, Ohio), who had
warned the Navy Department of the violent weather conditions that were common to
that area of Ohio in late summer. His pleas for a cancellation of the flight
only caused a temporary postponement: his superiors were keen to publicize
airship technology and justify the huge cost of the airship to the taxpayers.
So, as Lansdowne's widow consistently maintained at the inquiry, publicity
rather than prudence won the day. This event was the trigger for Army Colonel
Billy Mitchell to heavily criticize the leadership of both the Army and the
Navy, leading directly to his court-martial for insubordination and the end of
his military career. Heinen, according to the Daily Telegraph, placed the
mechanical fault for the disaster on the removal of eight of the craft's 18
safety valves, saying that without them he would not have flown on her "for a
million dollars". These valves had been removed in order to better preserve the
vessel's helium, which at that time was considered a limited global resource of
great rarity and strategic military importance; without these valves, the helium
contained in the rising gas bags had expanded too quickly for the bags' valves'
design capacity, causing the bags to tear apart the hull as they ruptured (of
course, the helium which had been contained in these bags became lost into the
upper atmosphere).
After the disaster, airship hulls were strengthened, control cabins were built
into the keels rather than suspended from cables, and engine power was
increased. More attention was also paid to weather forecasting.
General characteristics
Class and type: Shenandoah-class rigid airship
Tonnage: 77,500 lb (35,200 kg)
Length: 680 ft (207.26 m)
Beam: 78 ft 9 in (24.00 m) (maximum diameter)
Height: 93 ft 2 in (28.4 m)
Propulsion: Six (later five) 300 hp (220 kW) eight-cylinder Packard gasoline
engines
Speed: 60 kn (69 mph; 110 km/h)
Range: 5,000 mi (4,300 nmi; 8,000 km)
Capacity: Useful lift 53,600 lb (24,300 kg)
Complement: 25
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