Curtiss HS
Encyclopedia
The Curtiss HS was a single-engined patrol flying boat
built for the United States Navy
during World War I
. Large numbers were built from 1917 to 1919, with the type being used to carry out anti-submarine patrols from bases in France from June 1918. It remained in use with the US Navy until 1928, and was also widely used as a civil passenger and utility aircraft
, which was smaller than both the current Curtiss H-12
being built for Britain's Royal Naval Air Service
and the earlier Curtiss H-4, with the new design given the factory designation Model H-14, although its design was unrelated to earlier Model H variants. The H-14 was a conventional unequal-span, unstaggered biplane, powered by two 100 hp (75 kW) pusher
Curtiss OXX
engines mounted between the wings. An order for 16 was placed by the United States Army
before the prototype flew, but the prototype was disappointing, however, and the US Army cancelled its order for H-14s.
The prototype was converted to a single-engined aircraft powered by a 200 hp (149 kW) Curtiss V-X-X engine, also in a pusher configuration, during 1917, being redesignated as the Curtiss HS-1 (for H model with single engine). The prototype was re-engined for use as a test-bed for the new Liberty 12 engine, becoming the HS-1L, flying in this form on 21 October 1917.
While Curtiss's V-X-X engine proved to be inadequate, as it did in its larger Model H cousins, the Liberty proved more suitable, and large orders were placed by the US Navy for the HS-1L. The HS-1 was armed with two 180 lb (80 kg) depth bombs, but it was found that these bombs were too small. In order to carry more powerful 230 lb (100 kg) bombs, Curtiss produced an increased-span version, the HS-2 with span increased by 12 ft (3.66 m) and an additional set of interplane struts, giving four-bay wings rather than the three-bay wings of the HS-1L. Again, Curtiss specified one of their own engines, and again, the Navy substituted this with the Liberty engine in the definitive HS-2L.
The HS-3 was a further improved version with a new, wider hull flat-sided hull, that eliminated the typical Curtiss sponsons. The end of the war brought an end to plans to mass produce this version, only six being built.
The HS-1L and -2L were built in vast quantities: 675 by Curtiss themselves, and nearly as many again by various contractors that included L-W-F (250), Standard (80), Gallaudet Aircraft Company (60), Boeing
(25) and Loughead
(2). A further 25 were assembled by the US Navy from spare parts post war.
s on the Eastern Seaboard of the United States, and from the Panama Canal Zone
. Two HS-1Ls operating from Chatham, Massachusetts
made the only confirmed aircraft attack on a German U-boat
in American waters on July 21, 1918, but this was unsuccessful, with bombs failing to explode and the submarine escaping. From August 1918, in order to compensate for Canada's lack of patrol aircraft, US Navy HSs operated from two bases in Nova Scotia
. Twelve HS-2Ls were donated to Canada at the end of the war.
Large numbers of HS boats were also used by US Navy forces in France, with deliveries starting on May 24, 1918, flying their first patrols on June 13. About 160 HS-1Ls and -2Ls were deployed to France. Following the Armistice
, the HS boats based in Europe were scrapped apart from four aircraft based in the Azores, which were acquired by Portugal, while US Naval Air Service shrank considerably, with many Naval Air Stations closing, resulting in considerable numbers of HS boats becoming surplus to requirements and available for sale at $200 to $500 without engines. HS-2Ls continued in use by the US Navy as a patrol aircraft and a trainer until 1928.
Following the Armistice, eleven HSs passed into US Coast Guard service, remaining in service until 1926. As many as 83 HS boats were used by the United States Army Air Service
for communications and survey purposes from overseas bases, although they were not given US Army serial numbers.
Surplus HSs were also widely exported. Amongst Military users was Brazil, who received six aircraft in 1918. Two HS-2Ls were used in attempt to bomb the rebel held Forte de Copacabana during the 1922 Tenente revolt. Many were used in Canada as the first bush plane. One survives in the Canada Aviation Museum
in Ottawa
after being rescued from a Quebec lake.
Brazil
Canada
Mexico
United States
Flying boat
A flying boat is a fixed-winged seaplane with a hull, allowing it to land on water. It differs from a float plane as it uses a purpose-designed fuselage which can float, granting the aircraft buoyancy. Flying boats may be stabilized by under-wing floats or by wing-like projections from the fuselage...
built 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...
during World War I
World War I
World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...
. Large numbers were built from 1917 to 1919, with the type being used to carry out anti-submarine patrols from bases in France from June 1918. It remained in use with the US Navy until 1928, and was also widely used as a civil passenger and utility aircraft
Development and design
In late 1916, the Curtiss Aeroplane Company produced a new twin-engined flying boatFlying boat
A flying boat is a fixed-winged seaplane with a hull, allowing it to land on water. It differs from a float plane as it uses a purpose-designed fuselage which can float, granting the aircraft buoyancy. Flying boats may be stabilized by under-wing floats or by wing-like projections from the fuselage...
, which was smaller than both the current Curtiss H-12
Curtiss Model H
The Curtiss Model H was a family of classes of early long-range flying boats, the first two of which were developed directly on commission in the United States in response to the ₤10,000 prize challenge issued in 1913 by the London newspaper, the Daily Mail, for the first non-stop aerial crossing...
being built for Britain's Royal Naval Air Service
Royal Naval Air Service
The Royal Naval Air Service or RNAS was the air arm of the Royal Navy until near the end of the First World War, when it merged with the British Army's Royal Flying Corps to form a new service , the Royal Air Force...
and the earlier Curtiss H-4, with the new design given the factory designation Model H-14, although its design was unrelated to earlier Model H variants. The H-14 was a conventional unequal-span, unstaggered biplane, powered by two 100 hp (75 kW) pusher
Pusher configuration
In a craft with a pusher configuration the propeller are mounted behind their respective engine. According to Bill Gunston, a "pusher propeller" is one mounted behind engine so that drive shaft is in compression...
Curtiss OXX
Curtiss OXX
|-References:* Molson, K. M. "The Curtiss OX-5 Engine." Journal of the American Aviation Historical Society.* US Department of Transportation Federal Aviation Administration Type Certificate Data Sheet Curtiss OXX-6...
engines mounted between the wings. An order for 16 was placed by the United States Army
United States Army
The United States Army is the main branch of the United States Armed Forces responsible for land-based military operations. It is the largest and oldest established branch of the U.S. military, and is one of seven U.S. uniformed services...
before the prototype flew, but the prototype was disappointing, however, and the US Army cancelled its order for H-14s.
The prototype was converted to a single-engined aircraft powered by a 200 hp (149 kW) Curtiss V-X-X engine, also in a pusher configuration, during 1917, being redesignated as the Curtiss HS-1 (for H model with single engine). The prototype was re-engined for use as a test-bed for the new Liberty 12 engine, becoming the HS-1L, flying in this form on 21 October 1917.
While Curtiss's V-X-X engine proved to be inadequate, as it did in its larger Model H cousins, the Liberty proved more suitable, and large orders were placed by the US Navy for the HS-1L. The HS-1 was armed with two 180 lb (80 kg) depth bombs, but it was found that these bombs were too small. In order to carry more powerful 230 lb (100 kg) bombs, Curtiss produced an increased-span version, the HS-2 with span increased by 12 ft (3.66 m) and an additional set of interplane struts, giving four-bay wings rather than the three-bay wings of the HS-1L. Again, Curtiss specified one of their own engines, and again, the Navy substituted this with the Liberty engine in the definitive HS-2L.
The HS-3 was a further improved version with a new, wider hull flat-sided hull, that eliminated the typical Curtiss sponsons. The end of the war brought an end to plans to mass produce this version, only six being built.
The HS-1L and -2L were built in vast quantities: 675 by Curtiss themselves, and nearly as many again by various contractors that included L-W-F (250), Standard (80), Gallaudet Aircraft Company (60), Boeing
Boeing
The Boeing Company is an American multinational aerospace and defense corporation, founded in 1916 by William E. Boeing in Seattle, Washington. Boeing has expanded over the years, merging with McDonnell Douglas in 1997. Boeing Corporate headquarters has been in Chicago, Illinois since 2001...
(25) and Loughead
Lockheed Corporation
The Lockheed Corporation was an American aerospace company. Lockheed was founded in 1912 and later merged with Martin Marietta to form Lockheed Martin in 1995.-Origins:...
(2). A further 25 were assembled by the US Navy from spare parts post war.
Operational history
The HS-1L began to enter service early in 1918, flying anti-submarine patrols from a number of Naval Air StationNaval Air Station
A Naval Air Station is a military airbase, and consists of a permanent land-based operations locations for the military aviation division of the relevant branch of their Navy...
s on the Eastern Seaboard of the United States, and from the Panama Canal Zone
Panama Canal Zone
The Panama Canal Zone was a unorganized U.S. territory located within the Republic of Panama, consisting of the Panama Canal and an area generally extending 5 miles on each side of the centerline, but excluding Panama City and Colón, which otherwise would have been partly within the limits of...
. Two HS-1Ls operating from Chatham, Massachusetts
Chatham, Massachusetts
Chatham is a town in Barnstable County, Massachusetts, United States, Barnstable County being coextensive with Cape Cod. The population was 6,625 at the 2000 census...
made the only confirmed aircraft attack on a German U-boat
U-boat
U-boat is the anglicized version of the German word U-Boot , itself an abbreviation of Unterseeboot , and refers to military submarines operated by Germany, particularly in World War I and World War II...
in American waters on July 21, 1918, but this was unsuccessful, with bombs failing to explode and the submarine escaping. From August 1918, in order to compensate for Canada's lack of patrol aircraft, US Navy HSs operated from two bases in Nova Scotia
Nova Scotia
Nova Scotia is one of Canada's three Maritime provinces and is the most populous province in Atlantic Canada. The name of the province is Latin for "New Scotland," but "Nova Scotia" is the recognized, English-language name of the province. The provincial capital is Halifax. Nova Scotia is the...
. Twelve HS-2Ls were donated to Canada at the end of the war.
Large numbers of HS boats were also used by US Navy forces in France, with deliveries starting on May 24, 1918, flying their first patrols on June 13. About 160 HS-1Ls and -2Ls were deployed to France. Following the Armistice
Armistice with Germany (Compiègne)
The armistice between the Allies and Germany was an agreement that ended the fighting in the First World War. It was signed in a railway carriage in Compiègne Forest on 11 November 1918 and marked a victory for the Allies and a complete defeat for Germany, although not technically a surrender...
, the HS boats based in Europe were scrapped apart from four aircraft based in the Azores, which were acquired by Portugal, while US Naval Air Service shrank considerably, with many Naval Air Stations closing, resulting in considerable numbers of HS boats becoming surplus to requirements and available for sale at $200 to $500 without engines. HS-2Ls continued in use by the US Navy as a patrol aircraft and a trainer until 1928.
Following the Armistice, eleven HSs passed into US Coast Guard service, remaining in service until 1926. As many as 83 HS boats were used by the United States Army Air Service
United States Army Air Service
The Air Service, United States Army was a forerunner of the United States Air Force during and after World War I. It was established as an independent but temporary wartime branch of the War Department by two executive orders of President Woodrow Wilson: on May 24, 1918, replacing the Aviation...
for communications and survey purposes from overseas bases, although they were not given US Army serial numbers.
Surplus HSs were also widely exported. Amongst Military users was Brazil, who received six aircraft in 1918. Two HS-2Ls were used in attempt to bomb the rebel held Forte de Copacabana during the 1922 Tenente revolt. Many were used in Canada as the first bush plane. One survives in the Canada Aviation Museum
Canada Aviation Museum
The Canada Aviation and Space Museum is Canada's national aviation history museum. The museum is located in Ottawa, Ontario, Canada, at the Ottawa/Rockcliffe Airport...
in Ottawa
Ottawa
Ottawa is the capital of Canada, the second largest city in the Province of Ontario, and the fourth largest city in the country. The city is located on the south bank of the Ottawa River in the eastern portion of Southern Ontario...
after being rescued from a Quebec lake.
Variants
- HS-1 - prototype with Curtiss engine.
- HS-1L - early production version of HS-1 with Liberty engine and short span (62 ft 1 in (18.92 m)) wings.
- HS-2 - longer-span version with Curtiss engine
- HS-2L - definitive production version with Liberty engine and long span (74 ft 1 in (22.58 m)) wings.
- HS-3 - improved version of the HS-2L, with new, wider hull and larger fin. Only six aircraft were built.
- HS-3L - Canadian modified version of HS-2L with modified wings (Clark Y section). At least three converted.
Operators
- Argentine Naval AviationArgentine Naval AviationThe Argentine Naval Aviation is the naval aviation branch of the Argentine Navy and one of its four operational commands...
Brazil
- Brazilian NavyBrazilian NavyThe Brazilian Navy is a branch of the Brazilian Armed Forces responsible for conducting naval operations. It is the largest navy in Latin America...
acquired six HS-2Ls in July 1918.
Canada
- Canadian Air Force obtained 30 HS-2L.
Mexico- Peruvian NavyPeruvian NavyThe Peruvian Navy is the branch of the Peruvian Armed Forces tasked with surveillance, patrol and defense on lakes, rivers and the Pacific Ocean up to 200 nautical miles from the Peruvian littoral...
received at least three HS-2Ls in 1920, remaining in service until 1926.
- Portuguese Naval AviationPortuguese Naval AviationThe Portuguese Naval Aviation , was the air branch of the Portuguese Navy until 1952, and is today the command of the Navy responsible for the operation of the aircraft on board their ships...
took over four ex-US Navy HS boats based in the AzoresAzoresThe Archipelago of the Azores is composed of nine volcanic islands situated in the middle of the North Atlantic Ocean, and is located about west from Lisbon and about east from the east coast of North America. The islands, and their economic exclusion zone, form the Autonomous Region of the...
after the end of World War I, using them for training.
United States
- United States Army Air ServiceUnited States Army Air ServiceThe Air Service, United States Army was a forerunner of the United States Air Force during and after World War I. It was established as an independent but temporary wartime branch of the War Department by two executive orders of President Woodrow Wilson: on May 24, 1918, replacing the Aviation...
- United States Coast GuardUnited States Coast GuardThe United States Coast Guard is a branch of the United States Armed Forces and one of the seven U.S. uniformed services. The Coast Guard is a maritime, military, multi-mission service unique among the military branches for having a maritime law enforcement mission and a federal regulatory agency...
- United States Marine CorpsUnited States Marine CorpsThe United States Marine Corps is a branch of the United States Armed Forces responsible for providing power projection from the sea, using the mobility of the United States Navy to deliver combined-arms task forces rapidly. It is one of seven uniformed services of the United States...
- United States NavyUnited States NavyThe 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...