airships and balloons in World War Two
The U.S. Navy began
acquiring non-rigid airships toward the end of the 1920s. The first
non-rigid airship it acquired was an unusual airship because it was
metal-clad. Built by the Aircraft Development Corporation, the ZMC-2 was
the only metal-clad airship built. It was delivered to the Navy on
September 12, 1929, and saw experimental use and use on various
humanitarian missions. Although it was somewhat hard to control during
rough air, it remained in service for 12 years. When it was scrapped, its
airtime had exceeded 2,200 hours.
During the 1930s, the
Goodyear Tire and Rubber Company built a fleet of non-rigid airships, or
blimps, that it was using for advertising and barnstorming. The U.S. Navy
took advantage of Goodyear's expertise and hired Goodyear to build its new
airships. The first airship was the prototype K-1. Goodyear built the
envelope (the balloon), and the Naval Aircraft Factory built the control
car that hung below the envelope.
A K-type blimp landing at Lakehurst Naval Air Station, New Jersey.
This airship burned a new
type of fuel gas that resembled propane rather than the standard liquid
fuel. This fuel had some interesting properties. It could be contained in
cells within the airship envelope and, since it had approximately the same
density as air, the buoyancy of the airship did not change as the fuel was
burned. This kept the airship steady. It also was more efficient than
liquid gasoline and eliminated the need to compensate for the weight of
the fuel that burned during flight.
The K-1 was an experimental airship and the first type to have the control
car suspended inside the envelope
Testing of the K-1 began
on October 7, 1931, at Naval Air Station (NAS) Lakehurst in New Jersey.
She was the largest non-rigid airship the Navy had operated up to that
time. She performed moderately well and was used until September 1940.
Following the K-1, the
Navy began to purchase both the blimp envelope and the control car from
Goodyear. The first blimp was the Defender, which the Navy
purchased in 1935 and designated the G-1. She was lost in a midair
collision with another airship on June 8, 1942, and 12 people died in the
The Navy went on to
purchase additional G-type airships, followed by L-type airships in 1937.
The Navy used both for training and utility work. During World War II,
these airships were flown primarily from the Naval Air Station at Moffett
Field, California and from Lakehurst in New Jersey.
L-class airships on a training flight near Naval
Air Station Moffett Field, California, in February 1944
During this period, the
and Macon had both been lost—the Akron in 1933 and the
Macon in 1935. Consequently, the Navy stopped building rigid
airships completely and devoted more resources to non-rigid airships,
which were less expensive to build and operate than the rigid ships. The
Navy also took over jurisdiction for the airship program from the U.S.
Army Air Corps in 1937, which had shared responsibility for airships with
the Navy. The Naval Air Station at Lakehurst, New Jersey, was designated
the centre of operations.
The Navy began expanding
its fleet, and the K-type airship became the backbone of the Navy's
airships program. The K-2 debuted on December 6, 1938, at the Goodyear
facility in Akron, Ohio, and Goodyear delivered it to the Navy on December
16. At the time, she was the largest non-rigid airship in the Navy's
inventory, with a capacity of 404,000 cubic feet (11,440 cubic meters).
She became the prototype for the wartime K-series.
After the attack on Pearl
Harbour in 1941, the Navy asked the U.S. Congress for authorization to
purchase an increased number of airships. By June 1942, Congress had
authorized the construction of 200 airships, and during the war, Goodyear
built a total of 168. At its production peak, the company was turning out
11 airships monthly.
The later K series
airships were slightly larger and had a capacity of 416,000 to 425,000
cubic feet (11,780 to 12,035 cubic meters). They were 253 feet (76 meters)
long, and 60 feet (18 meters) in diameter, and were powered by two
425-horsepower (317-kilowatt) engines that gave a top speed of 50 miles
per hour (80 kilometres per hour). They were not fast, but unlike an
airplane that could remain airborne for only a few hours, a K-ship could
stay aloft for 60 hours.
A K-ship on patrol. Note the depth bombs on the
underside of the control car
The United States was the
only power to use airships during World War II, and the airships played a
small but important role. The Navy used them for minesweeping, search and
rescue, photographic reconnaissance, scouting, escorting convoys, and
antisubmarine patrols. Airships accompanied many ocean-going ships, both
military and civilian. Of the 89,000 ships escorted by airships during the
war, not one was lost to enemy action.
The Navy airships
patrolled an area of over three million square miles (7.8 million square
kilometres) over the Atlantic and Pacific oceans and the Mediterranean Sea
during the war. They could look down on the ocean surface and spot a
rising submarine and radio its position to the convoy's surface ships. The
Navy's blimps initially operated from bases on the east and west coasts of
the United States, the Gulf of Mexico, the Caribbean, and as far south as
Brazil. Later in the war, they also operated from bases at Cuers, France,
and Pisa, Italy. In 1944, six K-ships flew across the Atlantic Ocean to
Morocco, where they established a low-altitude antisubmarine barrier
across the Strait of Gibraltar.
Only one airship was lost
to enemy action. A surfaced German Uboat shot down the airship K-74
during a battle, but the K74 damaged the German submarine so badly that
it could not submerge and was sunk by British bombers in the North Sea
while it was en route to Germany for repairs.
Both the Allies and Japan
also used balloons during World War II. The Allies used barrage balloons
(small blimps) to suspend aerial cables in the sky and foul enemy bombers.
A World War II Japanese balloon bomb. Japan
released more than 9,000 bomb-bearing balloons beginning on November 3,
1944. It is estimated that nearly 1,000 reached North America.
From November 3, 1944 to
April 1945, the Japanese launched 9,000 balloons carrying small 33-pound
(15-kilogram) incendiary bombs over the Pacific Ocean in the hope that the
winds would carry them to the United States. These were called the Fu-Go
Weapon, and supposedly were a revenge bomb for the 1942 Doolittle raids on
Tokyo. It is estimated that nearly 1,000 bomb-bearing balloons reached
North America, landing in 16 U.S. States, Alaska, Canada, and Mexico. The
last one found in North America was in Alaska in 1955—its payload still
lethal. It was picked up by a 74th Air Rescue Squadron H-5
helicopter crew from Ladd Air Force Base near Fairbanks, Alaska.
Only six Americans were
known to have died from balloon bombs. On May 5, 1945, a balloon bomb
exploded and killed Elsie Mitchell and five children near Lakeview,
Oregon. Although these bombs were psychologically effective, the U.S.
press didn't publish news of them to prevent the Japanese from learning of
the effect they had on the American people.
After 1945, the Navy
continued to use helium blimps in antisubmarine warfare, intermediate
search missions, and early warning missions. Some were equipped with
extraordinarily large airborne radar sets for early offshore warning of
bomber attacks against the United States. Two of the largest airships were
the ZPG-2 at 324 feet (99 meters) in length and a capacity of 875,000
cubic feet (24,777 cubic meters) and the ZPG-3 at 403 feet (121 meters)
long and a capacity of 1,516,000 cubic feet (43,000 cubic meters)--the
largest blimp type ever built. An airship of this type could stay aloft
without refuelling for more than 200 hours.
On August 31, 1962, the
Navy ended its use of blimps. In the 1980s, the Navy looked once more at
reviving airships, but Congress terminated funding for the project in