Early Airships

ZR	name	first flight	crashed
	Roma	15 Nov 1921	21 Feb 1922
ZR-1	Shenandoah	04 Sep 1923	03 Sep 1925
ZR-2	R-38	Jun 1921	24 Aug 1921
ZR-3	Los Angeles	Aug 1924	N/A
ZRS-4	Akron	23 Sep 1931	04 Apr 1933
ZRS-5	Macon	Apr 1933	12 Feb 1935

Between the wars the United States operated six large airships, five of which were lost in accidents within a year or two of entering service. For all of their magnificence, dirigibles proved to be extremely vulnerable to weather and other hazards. The earliest versions used inflammable hydrogen gas, which caused the explosion on the Air Corps's airship Roma, followed by the better-known disaster on the German passenger dirigible Hindenberg. Even airships that used helium could be torn apart in rough weather, as the Navy discovered in losing the airships Shenandoah, Akron, and Macon. The Akron disaster cost the Navy 73 lives, including that of Admiral Moffett, chief of the Aeronautics Bureau.

Lighter-than-air craft consist of three distinct types: Airships, which are by far the most important, Free Balloons, and Kite Balloons [known more recently as tethered aerostates], which are attached to the ground or to a ship by a cable. They derive their appellation from the fact that they are lighter than the air which they displace. Of these three types the free balloon is by far the oldest and the simplest, but it is entirely at the mercy of the wind and other elements, and cannot be controlled for direction, but must drift whithersoever the wind or air currents take it. On the other hand, the airship, being provided with engines to propel it through the air, and with rudders and elevators to control it for direction and height, can be steered in whatever direction is desired, and voyages can be made from one place to another--always provided that the force of the wind is not sufficiently strong to overcome the power of the engines. The airship is, therefore, nothing else than a dirigible balloon, for the engines and other weights connected with the structure are supported in the air by an envelope or balloon, or a series of such chambers, according to design, filled with hydrogen or gas of some other nature.

Comparatively little progress had been made in the United States in airship building up to the American entry into the European war. A moderate size dirigible was designed and constructed by Cupt. Thomas S. Baldwin in 1908 and accepted by the government for the Army Signal Corpa. It had a capacity of 20,00O cubic feet and was driven by a 20-horsepower gasolina engine, developing a speed of about 20 miles per hour. Two airships were built by Melvin Vaniman. In one of those, named "America," Walter Wellinan tried to cross the Atlantic in 1910. The engines failed, however, and the airship drifted 1008 miles in 71 hours. The crew were rescued after abandoning the airship. Vaniman designed a new dirigible, the Akron, and essayed the flight to Europe with a crew of four men in 1912. An explosion totally destroyed the airship, Vaniman and his crew perishing.

A gallant attempt to accomplish tho flight across the ocean was made by the United States Navy dirigible, C-5, but this came to disaster on the afternoon of May 15, 1919, when after a successful flight from Montaiik, N.Y., to Halifax, N.S., the C-5 broke from its moorings, was blown out over the sea and destroyed. The first dirigible to fly over the Atlantic was the British rigid airship, R-34, on July 2-6, 1919.

The giant British dirigible R-38, which was to have been turned over to the American Navy as the ZR-2, collapsed and burned at Hull, England, August 24, 1921, killing 42 men, including 16 Americans. In 1924, Germany granted the Goodyear Tire and Rubber Company patent rights to build zeppelins in the United States. Goodyear built two ships for the U.S. Navy, the Akron and the Macon.