Curtiss Model H

{{short description|American 1914 long range flying boat}} {{Infobox aircraft |name = Model H family |image = Curtiss America 001.jpg |caption = Curtiss H-12 ''Large America'' in RNAS service. |type = Experimental flying boat |manufacturer = [[Curtiss Aeroplane and Motor Company]] |designer =  |first_flight = 23 June [[1914 in aviation|1914]] (''America'') |introduction = |retired = |status =  |primary_user = [[United States Navy]] |more_users = [[Royal Naval Air Service]] |produced =  |number_built = 478 |developed_from = [[Curtiss Model F]]<ref name='Carpenter'>{{cite web|last1=Carpenter Jr |first1=G. J. (Jack) |title=Photographs 1914 |url=http://www.glennhcurtiss.com/id49.htm |website=Glenn H. Curtiss Founder of The American Aviation Industry |access-date=15 December 2015 |location=Internet Archive – Way Back Machine |date=2005 |url-status=dead|archive-url=https://web.archive.org/web/20061020132010/http://www.glennhcurtiss.com/id49.htm |archive-date=October 20, 2006 }}</ref> |variants = [[Felixstowe F.1]] <br> [[Felixstowe F.2]] }}

The '''Curtiss Model H''' was a family of classes of early long-range [[flying boat]]s, the first two of which were developed directly on commission in the [[United States]] in response to the [[Daily Mail aviation prizes|£10,000 prize challenge]] issued in 1913 by the London newspaper, the ''[[Daily Mail]]'', 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]]) 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]] [[flying boat]] 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]] technology in the 1910s being as rapid and explosive as any technological advance has ever been.

[[File:Porte and Glenn Curtiss 5126120684 3472e7cc65 o.jpg|thumb|upright|right|Porte and Curtiss as they appeared in ''[[The New York Times]]'' 10 March 1914, standing next to a [[Curtiss Model F|Model F]].<ref name='Carpenter'/>]] When London's ''[[Daily Mail]]'' newspaper put up a [[Daily Mail aviation prizes|£10,000 prize]] for the [[Alcock and Brown|first non-stop aerial crossing of the Atlantic]] in 1913, American businessman [[Rodman Wanamaker]] became determined that the prize should go to an American aircraft and commissioned the [[Curtiss Aeroplane and Motor Company]] 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]] and [[John Cyril Porte]], spurred financially by the nationalistically motivated financing of air enthusiast [[Rodman Wanamaker]]. 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.<ref name='America'>{{cite web|title=Hammondsport, N.Y. Launching of Rodman Wanamaker's trans-Atlantic flyer "America."|url=https://www.britishpathe.com/video/launching-of-america/query/Curtiss+America|website=British Pathé|access-date=15 February 2018|date=22 June 1914}}</ref> The outcome was a scaled-up version of Curtiss' work for the United States Navy and his [[Curtiss Model F]].<ref name='Carpenter'/> With Porte also as [[Test pilot|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]] design with two-bay, unstaggered wings of unequal span with two tractor [[Inline engine (aviation)|engines]] mounted side by side above the [[fuselage]] 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. [[File:Porte & Hallett on "America".jpg|thumb|left|''Porte & Hallett on "America"'', following the launch on [[Keuka Lake]] at [[Hammondsport, New York|Hammondsport]], June 1914, showing the [[Curtiss OX-5]] engines.]] [[Ceremonial ship launching|Named]] ''America''<ref name='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]] 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 [[hydrofoils|fins]] to the sides of the bow to add hydrodynamic lift, but soon replaced these with [[sponson]]s to add more buoyancy. Both prototypes, once fitted with sponsons, were then called '''Model H-2'''s 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]], which also saw Porte, who was to pilot the ''America'' with [[George E. A. Hallett|George Hallett]], recalled to service with the British [[Royal Navy]].<ref>{{cite web|url= https://babel.hathitrust.org/cgi/pt?id=uiug.30112045459051&seq=154 |title= Porte |date=1915-02-01|publisher= Gas review v.8(1915) |access-date=2026-04-02}}</ref> Impressed by the capabilities he had witnessed, Porte urged the [[British Admiralty|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 (1906)|RMS ''Mauretania'']].<ref>{{cite news|title=Amsterdam Evening Recorder|date=30 September 1914|page=3}}</ref> This was followed by a decision to order a further 12 similar aircraft, one Model H-2 and the remaining as '''Model H-4'''s, four examples of the latter actually being assembled in the UK by [[Saunders-Roe|Saunders]]. 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]] 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 of Great Britain and Ireland|United Kingdom]] under [[John Cyril Porte]] 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.

[[File:Curtiss Model H-8 Flying Boat.jpg|thumb|left|Model H-8 prototype on [[Keuka Lake|Lake Keuka]], 1916.]] Curtiss next developed an enlarged version of the same design, designated the '''Model H-8''', with accommodation for four crew members. A [[prototype]] was constructed and offered to the [[United States Navy]], 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 America'''s, with the H-4s receiving the [[retronym]] '''Small America'''. [[File:Curtiss H-12 L - 001.jpg|thumb|left|Curtiss H-12L in U.S. Navy service.]] 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]] (RNAS) service the H-12 was re-engined with the 275 hp (205 kW) [[Rolls-Royce Eagle]] I<ref>{{cite web|last1=Hanlon|first1=Michael E.|title=Aircraft of the AEF|url=http://www.worldwar1.com/dbc/curth12.htm|website=Worldwar1.com|access-date=19 February 2018|date=2000}}</ref> and then the 375 hp (280 kW) Eagle VIII.<ref name="thetford naval 80-1">Thetford 1978, pp. 80–81.</ref> 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]] (designated '''Curtiss H-12L''').<ref name="US Navy 1911 p106-7">Swanborough and Bowers 1976, pp. 106–107.</ref>

Curiously, the Curtiss company designation '''Model H-14''' was applied to a completely unrelated design (see [[Curtiss HS]]), but the '''Model H-16''', introduced in 1917, represented the final step in the evolution of the Model H design.<ref name="US Navy 1911 p107">Swanborough and Bowers 1976, p. 107.</ref> 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.)<ref name=nan>Van Wyen 1969, p. 90</ref> 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]] and anti-[[Zeppelin]] patrols over the [[North Sea]]. 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.<ref name="thetford naval 80-1"/><ref name="thetford naval 82-3">Thetford 1978, pp. 82–83.</ref>

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.<ref name="US Navy 1911 p106-7"/> 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.<ref>{{cite journal |last=Darden |first=Colgate W. Jr. |year=1984 |title=Naval Aviation in World War I |journal=Proceedings |volume=110 |issue=11 |pages=163–166 |publisher=[[United States Naval Institute]] }}</ref>

==Variants== [[File:Curtiss H-16 1.jpg|thumb|right|Curtiss H-16 in U.S. Navy service.]] * '''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''<ref>{{cite book|last1=Johnson|first1=E.R.|title=American Flying Boats and Amphibious Aircraft: An Illustrated History|date=2009|publisher=McFarland|isbn=978-0786457083|page=302|url=https://books.google.com/books?id=AtqOSxG9N1YC&pg=PA302}}</ref> * '''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]] 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]]) ** '''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== ;{{BRA}} *[[Brazilian Naval Aviation]] ;{{CAN}} *[[Canadian Air Force (1920–24)|Canadian Air Force]] – two former Royal Air Force H-16 ''Large Americas'' as an [[Imperial Gift]]<ref>Sturtivant/Page 1992, p. 242</ref> ;{{NLD}} *[[Netherlands Naval Aviation Service|Royal Netherlands Naval Air Service]] – one Curtiss H-12 in service<ref>{{cite web|last1=Jonker|first1=K.W.|title=Felixstowe F2A|url=http://kw.jonker.co/index.php?option=com_content&view=article&id=658%3Afelixstowe-f2a-uk&catid=87&Itemid=549&showall=&limitstart=1&lang=en|website=Nederlandse Modelbouw en Luchtvaartsite Modelling and Aviation|publisher=K.W. Jonker|access-date=31 December 2014|url-status=bot: unknown|archive-url=https://web.archive.org/web/20150620165503/http://kw.jonker.co/index.php?option=com_content&view=article&id=658%3Afelixstowe-f2a-uk&catid=87&Itemid=549&showall=&limitstart=1&lang=en|archive-date=20 June 2015}}</ref> ;{{UK}} *[[Royal Naval Air Service]] *[[Royal Air Force]] **[[No. 228 Squadron RAF]] **[[No. 234 Squadron RAF]] **[[No. 240 Squadron RAF]] **[[No. 249 Squadron RAF]] ;{{USA}} *[[United States Navy]] *[[American Trans-Oceanic Company]]

==Specifications (Model H-12A)== {{Aircraft specs |ref=Curtiss Aircraft 1907–1947,<ref name=Bowers>{{cite book |last1=Bowers |first1=Peter M. |title=Curtiss aircraft, 1907–1947 |date=1979 |publisher=Putnam |location=London |isbn=0370100298 |pages=90–96}}</ref> British naval aircraft since 1912<ref name="Thetford">{{cite book |last1=Thetford |first1=Owen |title=British naval aircraft since 1912 |date=1991 |publisher=Naval Institute Press |location=Annapolis |isbn=1-55750-076-2 |pages=87–88 |edition=6th rev.}}</ref> |prime units?=imp  |crew=4 |capacity= |length ft=46 |length in=6 |length note= |span ft=92 |span in=8.5 |span note= |height ft=16 |height in=6 |height note= |wing area sqft=1216 |wing area note= |aspect ratio= |airfoil=RAF 6<ref name="Selig">{{cite web |last1=Lednicer |first1=David |title=The Incomplete Guide to Airfoil Usage |url=https://m-selig.ae.illinois.edu/ads/aircraft.html |website=m-selig.ae.illinois.edu |access-date=16 April 2019}}</ref> |empty weight lb=7293 |empty weight note= |gross weight lb=10650 |gross weight note= |max takeoff weight lb= |max takeoff weight note= |fuel capacity= |more general=  |eng1 number=2 |eng1 name=[[Rolls-Royce Eagle I]] |eng1 type=V-12 water-cooled piston engines |eng1 hp=275 |eng1 note=<br/> :::later ::{{cvt|345|hp}} [[Rolls-Royce Eagle VII]] :::or ::{{cvt|375|hp}} [[Rolls-Royce Eagle VIII]]

|prop blade number=4 |prop name=fixed-pitch propellers |prop dia ft= |prop dia in= |prop dia note=  |max speed mph=85 |max speed note=at {{cvt|2000|ft}} |cruise speed mph= |cruise speed note= |stall speed mph= |stall speed note= |never exceed speed mph= |never exceed speed note= |minimum control speed mph= |minimum control speed note= |range miles= |range note= |combat range miles= |combat range note= |ferry range miles= |ferry range note= |endurance=6 hours |ceiling ft=10800 |ceiling note= |g limits= |roll rate= |climb rate ftmin=336 |climb rate note= |time to altitude={{cvt|2000|ft}} in 3 minutes 18 seconds ; {{cvt|10000|ft}} in 29 minutes 48 seconds |wing loading lb/sqft= |wing loading note= |fuel consumption lb/mi= |power/mass= |thrust/weight=

|more performance=  |guns=4 × {{cvt|.303|in}} [[Lewis gun]]s on flexible mounts |bombs= 4 × {{cvt|100|lb}} or 2 × {{cvt|230|lb}} bombs below the wings |avionics= }}

==See also== * [[Sikorsky Ilya Muromets]] * [[Charles M. Olmsted]] * [[Anzani|British Anzani]]<ref>{{cite web|title=British Anzani – a company history|url=http://www.britishanzani.co.uk/History.htm|website=The British Anzani Archive|publisher=British Anzani Archive|access-date=18 September 2015|page=1|date=2000|archive-url=https://web.archive.org/web/20120206075213/http://www.britishanzani.co.uk/History.htm|archive-date=6 February 2012|url-status=dead}}</ref> * [[Tony Jannus]] {{aircontent  |related=  * [[Curtiss Model F]]<ref name='Carpenter'/> * [[White & Thompson No. 1 Seaplane]] * [[Porte Baby]]<ref name="Owers">{{cite journal|last1=Owers|first1=Colin|title=The Porte Baby|journal=Cross & Cockade International|date=2015|page=46|url=http://www.crossandcockade.com/uploads/Porte_Baby.pdf|access-date=24 August 2015}}</ref> * [[Curtiss Model T]] (Wanamaker Triplane) * [[Felixstowe F.1]] * [[Felixstowe F.2]] |similar aircraft=  * [[Norman Thompson N.T.4]] |sequence= |lists= |see also=  }}

==Notes== {{Reflist}}

==Bibliography== *{{cite journal |last1=Klaauw|first1=Bart van der|title=Unexpected Windfalls: Accidentally or Deliberately, More than 100 Aircraft 'arrived' in Dutch Territory During the Great War |journal=Air Enthusiast |date=March–April 1999 |issue=80 |pages=54–59 |issn=0143-5450}} *{{cite journal |last1=McMillan|first1=Paul|title=Round-Out |journal=Air Enthusiast |date=May–June 1999 |issue=81 |page=80 |issn=0143-5450}} * Roseberry, C.R. ''Glenn Curtiss: Pioneer of Flight''. Garden City, NY: Doubleday & Company, 1972. {{ISBN|0-8156-0264-2}}. * Shulman, Seth. ''Unlocking the Sky: Glen Hammond Curtiss and the Race to Invent the Airplane''. New York: [[HarperCollins]], 2002. {{ISBN|0-06-019633-5}}. * Ray Sturtivant and Gordon Page ''Royal Navy Aircraft Serials and Units 1911–1919'' [[Air-Britain]], 1992. {{ISBN|0 85130 191 6}} * Swanborough, Gordon and Peter M. Bowers. ''United States Navy Aircraft since 1911, Second edition''. London: Putnam, 1976. {{ISBN|0-370-10054-9}}. * Taylor, Michael J.H. ''Jane's Encyclopedia of Aviation''. London: Studio Editions, 1989, p. 281. {{ISBN|0-7106-0710-5}}. * Thetford, Owen. ''British Naval Aircraft since 1912'', Fourth edition. London: Putnam, 1978. {{ISBN|0-370-30021-1}}. * ''World Aircraft Information Files: File 891, Sheet 44–45''. London: Bright Star Publishing, 2002. * {{cite book |last=Van Wyen |first=Adrian O. |title =Naval Aviation in World War I |url=https://archive.org/details/navalaviationinw00wash |publisher =Chief of Naval Operations |date =1969 |location =Washington, D.C. }}

==External links== {{Commons category|Curtiss Model H}} *[http://www.iwm.org.uk/collections/item/object/1060008189 Sons of Our Empire]: Film of the Royal Naval Air Service at Felixstowe, including [[John Cyril Porte]], Curtiss Model H-2 and prototype [[Felixstowe F.1]] (No. 3580) fitted with [[Anzani 10-cylinder|Anzani]] engines, about August 1916. * {{YouTube|nceWSu8z-8o|Curtiss Model H}}: Film of flying boats at [[RNAS Felixstowe]], including an Anzani engined Curtiss H-4 taxiing, [[Felixstowe F.2|Felixstowe F.2A]] moved down a slipway on its beaching trolley and H-12 ''Large Americas'' being launched, one loaded with bombs, c.1917. * [https://www.youtube.com/watch?v=b_1Z_wxA2CY Reproduction ''America'' Flies, September 2008]. * [http://www.westernmorningnews.co.uk/patrol-U-boat-hunters-Tresco-protecting-Allied/story-21342483-detail/story.html That was the West that was: Scilly in the First World War]{{Dead link|date=July 2020 |bot=InternetArchiveBot |fix-attempted=yes }}: Article featuring the Curtiss H-12 at [[New Grimsby]] on the [[Scilly Isles]]. * [http://www.rafmuseum.org.uk/blog/flying-boats-over-the-north-sea/ Flying Boats over the North Sea]: Article including the Curtiss H-12. * [http://www.rafmuseum.org.uk/blog/flying-boats-over-the-westrn-approaches/ Flying boats] over the [[Western Approaches]]: Article including the Curtiss H-12.

[[Category:Curtiss aircraft|Model H]] [[Category:1910s United States experimental aircraft]] [[Category:Flying boats]] [[Category:Biplanes]] [[Category:Aircraft first flown in 1914]] [[Category:Twin piston-engined tractor aircraft]]