K class blimp
Encyclopedia
The K-class non-rigid airship
was a class of blimp
s built by the Goodyear Aircraft Company of Akron, Ohio
for the United States Navy
. These blimps were powered by two radial air-cooled engines mounted on outriggers on the side of the control car that hung under the envelope. Before and during World War II
, 135 K-class blimps were built, configured for patrol and anti-submarine warfare operations and were extensively used in the Navy’s anti-submarine efforts in the Atlantic and Pacific Ocean areas.
for future K-class airship purchases. K-2 flew for the first time at Akron, Ohio on December 6, 1938 and was delivered to the Navy at NAS Lakehurst, New Jersey on December 16. The envelope capacity of the K-2—404,000 ft³ (11,440 m³)—was the largest for any USN blimp up to that time. K-2 was flown extensively as a prototype, and continued to operate testing new equipment, techniques, and performing whatever tasks were needed, including combat patrols in World War II.
On October 24, 1940, the Navy awarded a contract to Goodyear for six airships (K-3 through K-8) that were assigned the designation Goodyear ZNP-K. These blimps were designed for patrol and escort duties and were delivered to the Navy in late 1941 and early 1942. K-3 through K-8 had only minor modifications to K-2s design, the only major change was in engines from Pratt & Whitney R-1340
-16s to Wright R-975-28s. The Wright engine/propeller combination proved excessively noisy and was replaced in later K-ships with the Pratt & Whitney engines. A series of orders for more K-class blimps followed. Twenty-one additional blimps (K-9 through K-30) were ordered on 14 October 1942. On 9 January 1943, 21 more blimps (K-31 through K-50) were ordered. The envelope size of K-9 through K-13 was increased to 416,000 ft³ (11,780 m³) and those delivered thereafter used an envelope of 425,000 ft³ (12,035 m³). The final contract for the K-class blimp were awarded in mid-1943 for 89 airships. Four blimps from this order were later canceled. The remaining deliveries were assigned numbers K-51 through K-136. But, the number K-136 was not assigned to a specific airship as the control car assigned for K-136 was used to replace the car for K-113. The original car for K-113 was destroyed in a fire.
ZNP-K
ZPK
ZP2K
ZP3K
ZP4K
ZP5K
ZSG-3
ZSG-3
ZS2G-1
(ASW) duties in the Atlantic and Pacific Oceans as well as the Mediterranean Sea
. All equipment was carried in a forty feet long control car. The installed communications and instrumentation equipment allowed night flying. The blimps were equipped with the ASG-type radar
, that had a detection range of 90 mi (144.8 km), sonobuoy
s, and magnetic anomaly detection (MAD) equipment. The K-ships carried four Mk-47 depth bombs, two in a bomb bay
and two externally, and were equipped with a 0.5 in (12.7 mm) Browning machine gun
in the forward part of the control car. An aircrew of 10 normally operated the K-ships, consisting of a command pilot, two co-pilots, a navigator/pilot, airship rigger, an ordnanceman, two mechanics, and two radiomen.
On 1 June 1944, two K-class blimps of United States Navy
(USN) Airship Patrol Squadron 14 (ZP-14) completed the first transatlantic crossing by non-rigid airship
s. K-123 and K-130 left South Weymouth, MA on 28 May 1944 and flew approximately 16 hours to Naval Station Argentia
, Newfoundland. From Argentia, the blimps flew approximately 22 hours to Lagens Field
on Terceira Island in the Azores. The final leg of the first transatlantic crossing was about a 20-hour flight from the Azores to Craw Field
in Port Lyautey (Kenitra
), French Morocco
. The first pair of K-ships were followed by K-109 & K-134 and K-112 & K-101 which left South Weymouth on 11 and 27 June 1944, respectively. These six blimps initially conducted nighttime anti-submarine warfare operations to complement the daytime missions flown by FAW-15 aircraft (PBYs and B-24s) using magnetic anomaly detection to locate U-boats in the relatively shallow waters around the Straits of Gibraltar. Later, ZP-14 K-ships conducted minespotting and minesweeping operations in key Mediterranean ports and various escort missions including that of the convoy carrying Franklin Roosevelt and Winston Churchill to the Yalta Conference in early 1945. In late April 1945, K-89 and K-114 left Weeksville NAS in North Carolina and flew a southern transatlantic route to NAS Bermuda
, the Azores, and Port Lyautey where they arrived on 1 May 1945 as replacements for Blimp Squadron ZP-14.
The ability of the K-ships to hover and operate at low altitudes and slow speeds resulted in detection of numerous enemy submarine
s as well as assisting in search and rescue missions. The K-ships had an endurance capability of over 24 hours which was an important factor in the employment of ASW tactics.
The mooring system for the K-ship was a 42 ft (12.8 m) high triangular mooring mast
that was capable of being towed by a tractor. For advance bases where moving the mooring mast was not needed, a stick mast was used. A large ground crew was needed to land the blimps and moor them to the mast.
During the war, one K-ship—K-74—was lost to enemy action when it was shot down by on 8 July 1943. The crew was picked up eight hours later, except for one man who drowned just before being rescued.
The last "K Ship"—K-43—was retired in March 1959.
The airship control cars (gondolas) of K-28 and K-47 are on display at the New England Air Museum
in Windsor Locks, CT and the National Naval Aviation Museum in Pensacola, FL, respectively.
(NTS) during the Operation Plumbbob
series of tests in 1957.
In April 1947, the General Board of the U.S. Navy modified the designation system for airships. The second character of the designator was dropped as the Board dropped the code for rigid airships so that the "N" for non-rigid was no longer needed. The designation for the K-class blimps then became ZPK.
In April 1954, the designation system for lighter-than-air airships was further modified so that it conformed to the designation system for heavier-than-air aircraft. By this time the ZPK blimps had been retired from service and only the later version K-Class blimps were in service. Under the 1954 system the ZP2K blimp became the ZSG-2, the ZP3K became the ZSG-3, the ZP4K became the ZSG-4, and the ZP5K became the ZS2G-1. In new designation system, the "Z" signified lighter-than-air; the "S" was the type denoting an anti-submarine warfare mission; the numeral (i.e., "2") was the model; and the "G" was the manufacturer’s letter. The final numeral denoted the series of the vehicle within the type/model.
Airship
An airship or dirigible is a type of aerostat or "lighter-than-air aircraft" that can be steered and propelled through the air using rudders and propellers or other thrust mechanisms...
was a class of blimp
Blimp
A blimp, or non-rigid airship, is a floating airship without an internal supporting framework or keel. A non-rigid airship differs from a semi-rigid airship and a rigid airship in that it does not have any rigid structure, neither a complete framework nor a partial keel, to help the airbag...
s built by the Goodyear Aircraft Company of Akron, Ohio
Akron, Ohio
Akron , is the fifth largest city in the U.S. state of Ohio and the county seat of Summit County. It is located in the Great Lakes region approximately south of Lake Erie along the Little Cuyahoga River. As of the 2010 census, the city had a population of 199,110. The Akron Metropolitan...
for the United States Navy
United States Navy
The United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S...
. These blimps were powered by two radial air-cooled engines mounted on outriggers on the side of the control car that hung under the envelope. Before and during World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
, 135 K-class blimps were built, configured for patrol and anti-submarine warfare operations and were extensively used in the Navy’s anti-submarine efforts in the Atlantic and Pacific Ocean areas.
Development
The K-class blimp was a product of the austere times of the American depression. In 1937, K-2 was ordered from Goodyear as part of a contract that also bought the L-1. The L-class was Goodyear’s standard advertising and passenger blimp. K-2 was the production prototypePrototype
A prototype is an early sample or model built to test a concept or process or to act as a thing to be replicated or learned from.The word prototype derives from the Greek πρωτότυπον , "primitive form", neutral of πρωτότυπος , "original, primitive", from πρῶτος , "first" and τύπος ,...
for future K-class airship purchases. K-2 flew for the first time at Akron, Ohio on December 6, 1938 and was delivered to the Navy at NAS Lakehurst, New Jersey on December 16. The envelope capacity of the K-2—404,000 ft³ (11,440 m³)—was the largest for any USN blimp up to that time. K-2 was flown extensively as a prototype, and continued to operate testing new equipment, techniques, and performing whatever tasks were needed, including combat patrols in World War II.
On October 24, 1940, the Navy awarded a contract to Goodyear for six airships (K-3 through K-8) that were assigned the designation Goodyear ZNP-K. These blimps were designed for patrol and escort duties and were delivered to the Navy in late 1941 and early 1942. K-3 through K-8 had only minor modifications to K-2s design, the only major change was in engines from Pratt & Whitney R-1340
Pratt & Whitney R-1340
|-See also:* Pratt & Whitney Wasp series* Pratt & Whitney R-985 Wasp Junior* Pratt & Whitney R-1535 Twin Wasp Junior* Pratt & Whitney R-1830 Twin Wasp-Bibliography:...
-16s to Wright R-975-28s. The Wright engine/propeller combination proved excessively noisy and was replaced in later K-ships with the Pratt & Whitney engines. A series of orders for more K-class blimps followed. Twenty-one additional blimps (K-9 through K-30) were ordered on 14 October 1942. On 9 January 1943, 21 more blimps (K-31 through K-50) were ordered. The envelope size of K-9 through K-13 was increased to 416,000 ft³ (11,780 m³) and those delivered thereafter used an envelope of 425,000 ft³ (12,035 m³). The final contract for the K-class blimp were awarded in mid-1943 for 89 airships. Four blimps from this order were later canceled. The remaining deliveries were assigned numbers K-51 through K-136. But, the number K-136 was not assigned to a specific airship as the control car assigned for K-136 was used to replace the car for K-113. The original car for K-113 was destroyed in a fire.
Variants
After World War II, a series of modified K-class blimps were introduced to the fleet. These modified blimps were designated:ZNP-K
- The original designation of the K-class blimps. Individual blimps were identified by a sequential suffix number, e.g. ZNP-K-2, ZNPK-8 etc. etc.. In everyday use only the K and numerical suffixes were used. Batches of blimps were built with sometimes major differences, but the designations remained in the ZNP-K range, until the later versions, listed below, emerged.
ZPK
- Revised designation of the ZNP-K series.
ZP2K
- A larger envelope with the volume increased to 527,000 ft³ (14,923 m³), re-designated ZSG-2.
ZP3K
- A larger envelope with the volume increased to 527,000 ft³ (14,923 m³), re-designated ZSG-3.
ZP4K
- Delivered in 1953, retaining the 527,000 ft³ (14,923 m³) envelope volume and length of 266 ft (81.08 m), re-designated ZSG-4 in 1954.
ZP5K
- Re-designated ZS2G-1
ZSG-3
- Re-designation of the ZP3K.
ZSG-3
- Re-designation of the ZP3K.
ZS2G-1
- Re-designation of the ZP5K.
Operational history
The K-ships were used for anti-submarine warfareAnti-submarine warfare
Anti-submarine warfare is a branch of naval warfare that uses surface warships, aircraft, or other submarines to find, track and deter, damage or destroy enemy submarines....
(ASW) duties in the Atlantic and Pacific Oceans as well as the Mediterranean Sea
Mediterranean Sea
The Mediterranean Sea is a sea connected to the Atlantic Ocean surrounded by the Mediterranean region and almost completely enclosed by land: on the north by Anatolia and Europe, on the south by North Africa, and on the east by the Levant...
. All equipment was carried in a forty feet long control car. The installed communications and instrumentation equipment allowed night flying. The blimps were equipped with the ASG-type radar
Radar
Radar is an object-detection system which uses radio waves to determine the range, altitude, direction, or speed of objects. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain. The radar dish or antenna transmits pulses of radio...
, that had a detection range of 90 mi (144.8 km), sonobuoy
Sonobuoy
A sonobuoy is a relatively small expendable sonar system that is dropped/ejected from aircraft or ships conducting anti-submarine warfare or underwater acoustic research....
s, and magnetic anomaly detection (MAD) equipment. The K-ships carried four Mk-47 depth bombs, two in a bomb bay
Bomb bay
The bomb bay or weapons bay on some military aircraft is a compartment to carry bombs, usually in the aircraft's fuselage, with "bomb bay doors" which open at the bottom. The bomb bay doors are opened and the bombs are dropped when over the target or at a specified launching point.Large-sized...
and two externally, and were equipped with a 0.5 in (12.7 mm) Browning machine gun
Machine gun
A machine gun is a fully automatic mounted or portable firearm, usually designed to fire rounds in quick succession from an ammunition belt or large-capacity magazine, typically at a rate of several hundred rounds per minute....
in the forward part of the control car. An aircrew of 10 normally operated the K-ships, consisting of a command pilot, two co-pilots, a navigator/pilot, airship rigger, an ordnanceman, two mechanics, and two radiomen.
On 1 June 1944, two K-class blimps of United States Navy
United States Navy
The United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S...
(USN) Airship Patrol Squadron 14 (ZP-14) completed the first transatlantic crossing by non-rigid airship
Blimp
A blimp, or non-rigid airship, is a floating airship without an internal supporting framework or keel. A non-rigid airship differs from a semi-rigid airship and a rigid airship in that it does not have any rigid structure, neither a complete framework nor a partial keel, to help the airbag...
s. K-123 and K-130 left South Weymouth, MA on 28 May 1944 and flew approximately 16 hours to Naval Station Argentia
Naval Station Argentia
Naval Station Argentia is a former base of the United States Navy that operated from 1941-1994. It was established in the community of Argentia in what was then the Dominion of Newfoundland, which later became the tenth Canadian province .-Construction:Established under the British-U.S...
, Newfoundland. From Argentia, the blimps flew approximately 22 hours to Lagens Field
Lajes Field
Lajes Field or Lajes Air Base , officially designated Air Base No. 4 , is a multi-use air field, home to the Portuguese Air Force Base Aérea Nº4 and Azores Air Zone Command , a United States Air Force detachment , and a regional air passenger terminal located near Lajes...
on Terceira Island in the Azores. The final leg of the first transatlantic crossing was about a 20-hour flight from the Azores to Craw Field
Kenitra Airport
Kenitra Air Base is a military airport in Kenitra, the capital city of the Gharb-Chrarda-Béni Hssen region in Morocco. It is also known as the Third Royal Air Force Base, operated by the Royal Moroccan Air Force.-History:...
in Port Lyautey (Kenitra
Kenitra
Kenitra is a city in Morocco, formerly known as Port Lyautey. It is a port on the Sebou River, has a population in 2004 of 359,142 and is the capital of the Gharb-Chrarda-Béni Hssen region. During the Cold War Kenitra's U.S...
), French Morocco
Morocco
Morocco , officially the Kingdom of Morocco , is a country located in North Africa. It has a population of more than 32 million and an area of 710,850 km², and also primarily administers the disputed region of the Western Sahara...
. The first pair of K-ships were followed by K-109 & K-134 and K-112 & K-101 which left South Weymouth on 11 and 27 June 1944, respectively. These six blimps initially conducted nighttime anti-submarine warfare operations to complement the daytime missions flown by FAW-15 aircraft (PBYs and B-24s) using magnetic anomaly detection to locate U-boats in the relatively shallow waters around the Straits of Gibraltar. Later, ZP-14 K-ships conducted minespotting and minesweeping operations in key Mediterranean ports and various escort missions including that of the convoy carrying Franklin Roosevelt and Winston Churchill to the Yalta Conference in early 1945. In late April 1945, K-89 and K-114 left Weeksville NAS in North Carolina and flew a southern transatlantic route to NAS Bermuda
Naval Air Station Bermuda
Naval Air Station Bermuda , was located on St. David's Island, Bermuda from 1970 to 1995, on the former site of Kindley Air Force Base...
, the Azores, and Port Lyautey where they arrived on 1 May 1945 as replacements for Blimp Squadron ZP-14.
The ability of the K-ships to hover and operate at low altitudes and slow speeds resulted in detection of numerous enemy submarine
Submarine
A submarine is a watercraft capable of independent operation below the surface of the water. It differs from a submersible, which has more limited underwater capability...
s as well as assisting in search and rescue missions. The K-ships had an endurance capability of over 24 hours which was an important factor in the employment of ASW tactics.
The mooring system for the K-ship was a 42 ft (12.8 m) high triangular mooring mast
Mooring mast
A mooring mast, or mooring tower, is a structure designed to allow for the docking of an airship outside of an airship hangar or similar structure...
that was capable of being towed by a tractor. For advance bases where moving the mooring mast was not needed, a stick mast was used. A large ground crew was needed to land the blimps and moor them to the mast.
During the war, one K-ship—K-74—was lost to enemy action when it was shot down by on 8 July 1943. The crew was picked up eight hours later, except for one man who drowned just before being rescued.
The last "K Ship"—K-43—was retired in March 1959.
The airship control cars (gondolas) of K-28 and K-47 are on display at the New England Air Museum
New England Air Museum
The New England Air Museum is located at Bradley International Airport, Windsor Locks, Connecticut, USA. The museum is housed in three large display buildings consisting of more than of exhibit space...
in Windsor Locks, CT and the National Naval Aviation Museum in Pensacola, FL, respectively.
Nuclear weapon effects tests
Several K-class blimps were used for weapon effects tests at the Nevada Test SiteNevada Test Site
The Nevada National Security Site , previously the Nevada Test Site , is a United States Department of Energy reservation located in southeastern Nye County, Nevada, about northwest of the city of Las Vegas...
(NTS) during the Operation Plumbbob
Operation Plumbbob
Operation Plumbbob was a series of nuclear tests conducted between May 28 and October 7, 1957, at the Nevada Test Site, following Operation Redwing, and preceding Operation Hardtack I...
series of tests in 1957.
Airship Designations
During the life of the K-class airship, the U.S. Navy used three different designation systems. From 1922 through World War II, the Navy used a four character designator. The K-class blimps were designated ZNP-K where the "Z" signified lighter-than-air; "N" denoted non-rigid; "P" denoted a patrol mission; and "K" denoted the type or class of airship.In April 1947, the General Board of the U.S. Navy modified the designation system for airships. The second character of the designator was dropped as the Board dropped the code for rigid airships so that the "N" for non-rigid was no longer needed. The designation for the K-class blimps then became ZPK.
In April 1954, the designation system for lighter-than-air airships was further modified so that it conformed to the designation system for heavier-than-air aircraft. By this time the ZPK blimps had been retired from service and only the later version K-Class blimps were in service. Under the 1954 system the ZP2K blimp became the ZSG-2, the ZP3K became the ZSG-3, the ZP4K became the ZSG-4, and the ZP5K became the ZS2G-1. In new designation system, the "Z" signified lighter-than-air; the "S" was the type denoting an anti-submarine warfare mission; the numeral (i.e., "2") was the model; and the "G" was the manufacturer’s letter. The final numeral denoted the series of the vehicle within the type/model.
Specifications (K-14)
See also
- Hitchcock Naval Air StationHitchcock Naval Air StationHitchcock Naval Air Station was a Naval Air Station built by the United States Navy during World War II to accommodate lighter-than-air aircraft, more commonly known as blimps. It was located in the small town of Hitchcock, Texas, about fifteen miles northwest of Galveston. Construction began in...
, TexasTexasTexas is the second largest U.S. state by both area and population, and the largest state by area in the contiguous United States.The name, based on the Caddo word "Tejas" meaning "friends" or "allies", was applied by the Spanish to the Caddo themselves and to the region of their settlement in...