The Curtiss Model H was a family of classes of early long-range
flying boat
A flying boat is a type of seaplane with a hull, allowing it to land on water. It differs from a floatplane in having a fuselage that is purpose-designed for flotation, while floatplanes rely on fuselage-mounted floats for buoyancy.
Though ...
s, the first two of which were developed directly on commission in the
United States
The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...
in response to the
£10,000 prize challenge issued in 1913 by the London newspaper, the ''
Daily Mail
The ''Daily Mail'' is a British daily Middle-market newspaper, middle-market Tabloid journalism, tabloid conservative newspaper founded in 1896 and published in London. , it has the List of newspapers in the United Kingdom by circulation, h ...
'', for the first non-stop aerial crossing of the Atlantic. As the first aircraft having transatlantic range and cargo-carrying capacity, it became the grandfather development leading to early international commercial air travel, and by extension, to the modern world of commercial aviation. The last widely produced class, the Model H-12, was retrospectively designated Model 6 by Curtiss' company in the 1930s, and various classes have variants with suffixed letters indicating differences.
Design and development
Having transatlantic range and cargo carrying capacity by design, the first H-2 class (soon dubbed ''"The Americans"'' by the
Royal Navy
The Royal Navy (RN) is the naval warfare force of the United Kingdom. It is a component of His Majesty's Naval Service, and its officers hold their commissions from the King of the United Kingdom, King. Although warships were used by Kingdom ...
) was quickly drafted into wartime use as a patrol and rescue aircraft by the RNAS, the air arm of the British Royal Navy. The original two "contest" aircraft were in fact temporarily seized by the Royal Navy, which later paid for them and placed an initial follow-on order for an additional 12 – all 14 of which were militarized (e.g. by adding gun mounts) and designated the "H-4" (the two originals were thereafter the "H-2" Models to air historians). These changes were produced under contract from Curtiss' factory in the last order of 50 "H-4s", giving a class total of 64, before the evolution of a succession of larger, more adaptable, and more robust H-class models. This article covers the whole line of nearly 500 Curtiss Model H
seaplane
A seaplane is a powered fixed-wing aircraft capable of takeoff, taking off and water landing, landing (alighting) on water.Gunston, "The Cambridge Aerospace Dictionary", 2009. Seaplanes are usually divided into two categories based on their tech ...
flying boat
A flying boat is a type of seaplane with a hull, allowing it to land on water. It differs from a floatplane in having a fuselage that is purpose-designed for flotation, while floatplanes rely on fuselage-mounted floats for buoyancy.
Though ...
aircraft known to have been produced, since successive models – by whatever sub-model designation – were physically similar, handled similarly, essentially just being increased in size and fitted with larger and improved engines – the advances in
internal combustion engine
An internal combustion engine (ICE or IC engine) is a heat engine in which the combustion of a fuel occurs with an oxidizer (usually air) in a combustion chamber that is an integral part of the working fluid flow circuit. In an internal comb ...
technology in the 1910s being as rapid and explosive as any technological advance has ever been.

When London's ''
Daily Mail
The ''Daily Mail'' is a British daily Middle-market newspaper, middle-market Tabloid journalism, tabloid conservative newspaper founded in 1896 and published in London. , it has the List of newspapers in the United Kingdom by circulation, h ...
'' newspaper put up a
£10,000 prize for the
first non-stop aerial crossing of the Atlantic in 1913, American businessman
Rodman Wanamaker
Lewis Rodman Wanamaker (February 13, 1863 – March 9, 1928) was an American businessman and heir to the Wanamaker's department store fortune. In addition to operating stores in Philadelphia, New York City, and Paris, he was a patron of the ar ...
became determined that the prize should go to an American aircraft and commissioned the
Curtiss Aeroplane and Motor Company
The Curtiss Aeroplane and Motor Company (1909–1929) was an American aircraft manufacturer originally founded by Glenn Curtiss, Glenn Hammond Curtiss and Augustus Moore Herring in Hammondsport, New York. After significant commercial success in ...
to design and build an aircraft capable of making the flight. The ''Mail''s offer of a large monetary prize for "an aircraft with transoceanic range" (in an era with virtually no airports) galvanized air enthusiasts worldwide, and in America, prompted a collaboration between the American and British air pioneers:
Glenn Curtiss
Glenn Hammond Curtiss (May 21, 1878 – July 23, 1930) was an American aviation and motorcycling pioneer, and a founder of the U.S. aircraft industry. He began his career as a bicycle racer and builder before moving on to motorcycles. As early a ...
and
John Cyril Porte
Lieutenant Colonel John Cyril Porte, (26 February 1884 – 22 October 1919) was a British flying boat aviation pioneer, pioneer associated with the First World War Seaplane Experimental Station at Felixstowe.
Early life and career
Porte was b ...
, spurred financially by the nationalistically motivated financing of air enthusiast
Rodman Wanamaker
Lewis Rodman Wanamaker (February 13, 1863 – March 9, 1928) was an American businessman and heir to the Wanamaker's department store fortune. In addition to operating stores in Philadelphia, New York City, and Paris, he was a patron of the ar ...
. The class, while commissioned by Wanamaker, was designed under Porte's supervision following his study and rearrangement of the flight plan and built in the Curtiss workshops.
The outcome was a scaled-up version of Curtiss' work for the United States Navy and his
Curtiss Model F.
With Porte also as
Chief Test Pilot, development and testing of two prototypes proceeded rapidly, despite the inevitable surprises and teething troubles inherent in new engines, hull and fuselage.
The ''Wanamaker Flier'' was a conventional
biplane
A biplane is a fixed-wing aircraft with two main wings stacked one above the other. The first powered, controlled aeroplane to fly, the Wright Flyer, used a biplane wing arrangement, as did many aircraft in the early years of aviation. While ...
design with two-bay, unstaggered wings of unequal span with two tractor
engines
An engine or motor is a machine designed to convert one or more forms of energy into mechanical energy.
Available energy sources include potential energy (e.g. energy of the Earth's gravitational field as exploited in hydroelectric power gen ...
mounted side by side above the
fuselage
The fuselage (; from the French language, French ''fuselé'' "spindle-shaped") is an aircraft's main body section. It holds Aircrew, crew, passengers, or cargo. In single-engine aircraft, it will usually contain an Aircraft engine, engine as wel ...
in the interplane gap. Wingtip pontoons were attached directly below the lower wings near their tips. The aircraft resembled Curtiss' earlier flying boat designs, but was considerably larger in order to carry enough fuel to cover 1,100 mi (1,770 km). The three crew members were accommodated in a fully enclosed cabin.
Named ''America''
and launched 22 June 1914, trials began the following day and soon revealed a serious shortcoming in the design: the tendency for the nose of the aircraft to try to submerge as engine power increased while
taxiing
Taxiing (rarely spelled taxying) is the movement of an aircraft on the ground, under its own power, in contrast to towing or pushback (aviation), pushback where the aircraft is moved by a tug. The aircraft usually moves on wheels, but the term ...
on water. This phenomenon had not been encountered before, since Curtiss' earlier designs had not used such powerful engines. In order to counteract this effect, Curtiss fitted
fins
A fin is a thin component or appendage attached to a larger body or structure. Fins typically function as foil (fluid mechanics), foils that produce lift (force), lift or thrust, or provide the ability to steer or stabilize motion while travelin ...
to the sides of the bow to add hydrodynamic lift, but soon replaced these with
sponson
Sponsons are projections extending from the sides of land vehicles, aircraft or watercraft to provide protection, Instantaneous stability, stability, storage locations, mounting points for weapons or other devices, or equipment housing.
Watercra ...
s to add more buoyancy. Both prototypes, once fitted with sponsons, were then called Model H-2s incrementally updated alternating in succession. These sponsons would remain a prominent feature of flying boat hull design in the decades to follow. With the problem resolved, preparations for the transatlantic crossing resumed, and 5 August 1914 was selected to take advantage of the
full moon.
These plans were interrupted by the outbreak of the
First World War
World War I or the First World War (28 July 1914 – 11 November 1918), also known as the Great War, was a World war, global conflict between two coalitions: the Allies of World War I, Allies (or Entente) and the Central Powers. Fighting to ...
, which also saw Porte, who was to pilot the ''America'' with
George Hallett, recalled to service with the British
Royal Navy
The Royal Navy (RN) is the naval warfare force of the United Kingdom. It is a component of His Majesty's Naval Service, and its officers hold their commissions from the King of the United Kingdom, King. Although warships were used by Kingdom ...
. Impressed by the capabilities he had witnessed, Porte urged the
Admiralty to commandeer (and later, purchase) the ''America'' and her sister aircraft from Curtiss. By the late summer of 1914 they were both successfully fully tested and shipped to England 30 September, aboard
RMS ''Mauretania''. This was followed by a decision to order a further 12 similar aircraft, one Model H-2 and the remaining as Model H-4s, four examples of the latter actually being assembled in the UK by
Saunders
Saunders is a surname of English and Scottish origin, derived from ''Sander'', a mediaeval form of Alexander.See also: Sander (name)
People
* Ab Saunders (1851–1883), American cowboy and gunman
* Al Saunders (born 1947), American football c ...
. All of these were essentially identical to the design of the ''America'', and indeed, were all referred to as "Americas" in Royal Navy service. This initial batch was followed by an order for another 50.
These aircraft were soon of great interest to the
British Admiralty
The Admiralty was a Departments of the Government of the United Kingdom, department of the Government of the United Kingdom that was responsible for the command of the Royal Navy.
Historically, its titular head was the Lord High Admiral of the ...
as anti-submarine patrol craft and for air-sea rescue roles. The initial Royal Navy purchase of just two aircraft eventually spawned a fleet of aircraft which saw extensive military service during World War I in these roles, being extensively developed in the process (together with many spinoff or offspring variants) under the compressed research and development cycles available in wartime. Consequently, as the war progressed, the Model H was developed into progressively larger variants, and it served as the basis for parallel developments in the
United Kingdom
The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Northwestern Europe, off the coast of European mainland, the continental mainland. It comprises England, Scotlan ...
under
John Cyril Porte
Lieutenant Colonel John Cyril Porte, (26 February 1884 – 22 October 1919) was a British flying boat aviation pioneer, pioneer associated with the First World War Seaplane Experimental Station at Felixstowe.
Early life and career
Porte was b ...
which led to the "Felixstowe" series of flying boats with their better hydrodynamic hull forms, beginning with the
Felixstowe F.1 — a hull form which thereafter became the standard in seaplanes of all kinds, just as sponsons did for flying boats.

Curtiss next developed an enlarged version of the same design, designated the Model H-8, with accommodation for four crew members. A
prototype
A prototype is an early sample, model, or release of a product built to test a concept or process. It is a term used in a variety of contexts, including semantics, design, electronics, and Software prototyping, software programming. A prototype ...
was constructed and offered to the
United States Navy
The United States Navy (USN) is the naval warfare, maritime military branch, service branch of the United States Department of Defense. It is the world's most powerful navy with the largest Displacement (ship), displacement, at 4.5 millio ...
, but was ultimately also purchased by the British Admiralty. This aircraft would serve as the pattern for the Model H-12, used extensively by both the Royal Navy and the United States Navy. Upon their adoption into service by the RNAS, they became known as Large Americas, with the H-4s receiving the
retronym
A retronym is a newer name for something that differentiates it from something else that is newer, similar, or seen in everyday life; thus, avoiding confusion between the two.
Etymology
The term ''retronym'', a neologism composed of the combi ...
Small America.

As built, the Model H-12s had 160 hp (118 kW)
Curtiss V-X-X engines, but these engines were under powered and deemed unsatisfactory by the British so in
Royal Naval Air Service
The Royal Naval Air Service (RNAS) was the air arm of the Royal Navy, under the direction of the Admiralty (United Kingdom), Admiralty's Air Department, and existed formally from 1 July 1914 to 1 April 1918, when it was merged with the British ...
(RNAS) service the H-12 was re-engined with the 275 hp (205 kW)
Rolls-Royce Eagle
The Rolls-Royce Eagle was the first aircraft engine to be developed by Rolls-Royce Limited. Introduced in 1915 to meet British military requirements during World War I, it was used to power the Handley Page Type O bombers and a number of oth ...
I and then the 375 hp (280 kW) Eagle VIII.
[Thetford 1978, pp. 80–81.] Porte redesigned the H-12 with an improved hull; this design, the
Felixstowe F.2, was produced and entered service. Some of the H-12s were later rebuilt with a hull similar to the F.2, these rebuilds being known as the Converted Large America. Later aircraft for the U.S. Navy received the
Liberty engine
The Liberty L-12 is an American water-cooled 45° V-12 engine, displacing and making , designed for a high power-to-weight ratio and ease of mass production. It was designed principally as an aircraft engine and saw wide use in aero applicat ...
(designated Curtiss H-12L).
[Swanborough and Bowers 1976, pp. 106–107.]
Curiously, the Curtiss company designation Model H-14 was applied to a completely unrelated design (see
Curtiss HS
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 1 ...
), but the Model H-16, introduced in 1917, represented the final step in the evolution of the Model H design.
[Swanborough and Bowers 1976, p. 107.] With longer-span wings, and a reinforced hull similar to the Felixstowe flying boats, the H-16s were powered by Liberty engines in U.S. Navy service and by Eagle IVs for the Royal Navy. These aircraft remained in service through the end of World War I. Some were offered for sale as surplus military equipment at $11,053 apiece (one third of the original purchase price.)
[Van Wyen 1969, p. 90] Others remained in U.S. Navy service for some years after the war, most receiving engine upgrades to more powerful Liberty variants.
Operational history
With the RNAS, H-12s and H-16s operated from flying boat stations on the coast in long-range anti-
submarine
A submarine (often shortened to sub) is a watercraft capable of independent operation underwater. (It differs from a submersible, which has more limited underwater capability.) The term "submarine" is also sometimes used historically or infor ...
and anti-
Zeppelin
A Zeppelin is a type of rigid airship named after the German inventor Ferdinand von Zeppelin () who pioneered rigid airship development at the beginning of the 20th century. Zeppelin's notions were first formulated in 1874Eckener 1938, pp. 155� ...
patrols over the
North Sea
The North Sea lies between Great Britain, Denmark, Norway, Germany, the Netherlands, Belgium, and France. A sea on the European continental shelf, it connects to the Atlantic Ocean through the English Channel in the south and the Norwegian Se ...
. A total of 71 H-12s and 75 H-16s were received by the RNAS, commencing patrols in April 1917, with 18 H-12s and 30 H-16s remaining in service in October 1918.
[Thetford 1978, pp. 82–83.]
U.S. Navy H-12s were kept at home and did not see foreign service, but ran anti-submarine patrols from their own naval stations. Twenty aircraft were delivered to the U.S. Navy.
Some of the H-16s, however, arrived at bases in the UK in time to see limited service just before the cessation of hostilities. Navy pilots disliked H-16 because, in the event of a crash landing, the large engines above and behind the cockpit were likely to break loose and continue forward striking the pilot.
Variants

* Model H-1 or Model 6: original ''America'' intended for transatlantic crossing (two prototypes built)
* Model H-2 (one built)
* Model H-4: similar to H-1 for RNAS (62 built)
* Model H-7: ''Super America''
* Model H-8: enlarged version of the H-4 (one prototype built)
* Model H-12 or Model 6A: production version of H-8 with
Curtiss V-X-X engines (104 built)
** Model H-12A or Model 6B: RNAS version re-engined with
Rolls-Royce Eagle
The Rolls-Royce Eagle was the first aircraft engine to be developed by Rolls-Royce Limited. Introduced in 1915 to meet British military requirements during World War I, it was used to power the Handley Page Type O bombers and a number of oth ...
I
** Model H-12B or Model 6D: RNAS version re-engined with Rolls-Royce Eagle VIII
** Model H-12L: USN version re-engined with Liberty engine
* Model H-16 or Model 6C: enlarged version of H-12 (334 built by Curtiss and
Naval Aircraft Factory
The Naval Aircraft Factory (NAF) was established by the United States Navy in 1918 in Philadelphia, Pennsylvania. It was created to help solve aircraft supply issues which the United States Department of the Navy, Navy Department faced upon the ...
)
** Model H-16-1: Model 16 fitted with pusher engines (one built)
** Model H-16-2: Model 16 fitted with pusher engines and revised wing cellule (one built)
Operators
;
*
Brazilian Naval Aviation
The Brazilian Naval Aviation () is the air component of the Brazilian Navy, currently called ''Força Aeronaval''. Most of its air structure is subordinated to the Naval Air Force Command (''Comando da Força Aeronaval'', ComForAerNav), the milita ...
;
*
Canadian Air Force
The Royal Canadian Air Force (RCAF; ) is the air and space force of Canada. Its role is to "provide the Canadian Forces with relevant, responsive and effective airpower". The RCAF is one of three environmental commands within the unified Cana ...
– two former Royal Air Force H-16 ''Large Americas'' as an
Imperial Gift
;
*
Royal Netherlands Naval Air Service – one Curtiss H-12 in service
;
*
Royal Naval Air Service
The Royal Naval Air Service (RNAS) was the air arm of the Royal Navy, under the direction of the Admiralty (United Kingdom), Admiralty's Air Department, and existed formally from 1 July 1914 to 1 April 1918, when it was merged with the British ...
*
Royal Air Force
The Royal Air Force (RAF) is the Air force, air and space force of the United Kingdom, British Overseas Territories and Crown Dependencies. It was formed towards the end of the World War I, First World War on 1 April 1918, on the merger of t ...
**
No. 228 Squadron RAF
**
No. 234 Squadron RAF
**
No. 240 Squadron RAF
**
No. 249 Squadron RAF
;
*
United States Navy
The United States Navy (USN) is the naval warfare, maritime military branch, service branch of the United States Department of Defense. It is the world's most powerful navy with the largest Displacement (ship), displacement, at 4.5 millio ...
*
American Trans-Oceanic Company
American Trans-Oceanic Company was an airline based in the United States.
History
Rodman Wanamaker published a letter in 1916 stating the founding of the American Trans-Oceanic Company to capitalize on the 1914 effort to fly across the Atlan ...
Specifications (Model H-12A)
See also
*
Sikorsky Ilya Muromets
The Sikorsky ''Ilya Muromets'' (; versions S-22, S-23, S-24, S-25, S-26 and S-27) was a class of Russian pre-World War I large four-engine commercial airliners and military heavy bombers used during World War I by the Russian Empire. The air ...
*
Charles M. Olmsted
*
British Anzani
*
Tony Jannus
Antony Habersack Jannus, more familiarly known as Tony Jannus (July 22, 1889 – October 12, 1916), was an early American pilot whose aerial exploits were widely publicized in aviation's pre-World War I period. He flew the first airplane from ...
Notes
Bibliography
*
*
* Roseberry, C.R. ''Glenn Curtiss: Pioneer of Flight''. Garden City, NY: Doubleday & Company, 1972. .
* Shulman, Seth. ''Unlocking the Sky: Glen Hammond Curtiss and the Race to Invent the Airplane''. New York:
HarperCollins
HarperCollins Publishers LLC is a British–American publishing company that is considered to be one of the "Big Five (publishers), Big Five" English-language publishers, along with Penguin Random House, Hachette Book Group USA, Hachette, Macmi ...
, 2002. .
* Ray Sturtivant and Gordon Page ''Royal Navy Aircraft Serials and Units 1911–1919''
Air-Britain
Air-Britain, traditionally sub-titled 'The International Association of Aviation Enthusiasts', is a non-profit aviation society founded in July 1948. As from 2015, it is constituted as a British charitable trust and book publisher.
History
Air-Br ...
, 1992.
* Swanborough, Gordon and Peter M. Bowers. ''United States Navy Aircraft since 1911, Second edition''. London: Putnam, 1976. .
* Taylor, Michael J.H. ''Jane's Encyclopedia of Aviation''. London: Studio Editions, 1989, p. 281. .
* Thetford, Owen. ''British Naval Aircraft since 1912'', Fourth edition. London: Putnam, 1978. .
* ''World Aircraft Information Files: File 891, Sheet 44–45''. London: Bright Star Publishing, 2002.
*
External links
Sons of Our Empire Film of the Royal Naval Air Service at Felixstowe, including
John Cyril Porte
Lieutenant Colonel John Cyril Porte, (26 February 1884 – 22 October 1919) was a British flying boat aviation pioneer, pioneer associated with the First World War Seaplane Experimental Station at Felixstowe.
Early life and career
Porte was b ...
, Curtiss Model H-2 and prototype
Felixstowe F.1 (No. 3580) fitted with
Anzani engines, about August 1916.
* : Film of flying boats at
RNAS Felixstowe, including an Anzani engined Curtiss H-4 taxiing,
Felixstowe F.2A moved down a slipway on its beaching trolley and H-12 ''Large Americas'' being launched, one loaded with bombs, c.1917.
Reproduction ''America'' Flies, September 2008
Article featuring the Curtiss H-12 at
New Grimsby on the
Scilly Isles
The Isles of Scilly ( ; ) are a small archipelago off the southwestern tip of Cornwall, England. One of the islands, St Agnes, is over farther south than the most southerly point of the British mainland at Lizard Point, and has the souther ...
.
Flying Boats over the North Sea Article including the Curtiss H-12.
Flying boatsover the
Western Approaches
The Western Approaches is an approximately rectangular area of the Atlantic Ocean lying immediately to the west of Ireland and parts of Great Britain. Its north and south boundaries are defined by the corresponding extremities of Britain. The c ...
: Article including the Curtiss H-12.
{{Authority control
Model H
1910s United States experimental aircraft
Flying boats
Biplanes
Aircraft first flown in 1914
Twin piston-engined tractor aircraft