Always a subject for controversy, Glenn Curtiss and his flying machines have long represented an historian's nightmare. Documentation was not a first-order priority among most pioneer aircraft builders, and Curtiss as one offers a choice of the three basic versions for his creations: (1) none, (2) some, and (3) too much. Within the Curtiss envelope, there are subcontroversies, a popular one being the Models C, D, E, and F flying boats (Hydroaeroplanes).
We present here not a solution there probably is no such thing but a forum where fact, folklore, and conjecture might be brought to an acceptable common ground. Or maybe not. We will not editorialize or edit, but leave it up to those who enjoy untying knots and poking around in the dark corners of history to work it out. Interpretation is up to the individual author, historian, or speculator, and each is equally valid in this arena.
Our forum was born on AeroFiles' "ID Needed" page when we ran several pictures and requested viewer input, and it went from there to here:
Bill Devins (7/11/01): The problem with the early Curtiss 'boats is their lack of real designations. Most of them were called Model F-Boats, but even then they have to be sorted by year and period. I think there was a totally unrelated Model F landplane of 1912, as well. This is apparently an early-1914 Curtiss F-Boat which bears features of the first 6 exported to Russia that year tip floats fitted at the edge of the wingtip without any overhang, small stabilizer with reduced leading-edge sweep angle compared to later 1914 F-boats, rounded forward hull top compared to earlier E- and F-Boats, etc. The dark diagonal on the starboard wing is an artist's overexaggeration of the aileron upper drag wire, as you suggest (SEE Devins follow-up below).
Carl Stidsen (7/17/01): I suspect it is not an F-Boat, but is more likely a late Curtiss E, possibly the Navy C-1. Both the E and the Russian Fs had the triangular wing extensions and support strut. Most American Fs had larger outer wing panel additions than that shown in the photo. Photos I've found of the Russian F-Boats (and early E-Boats) show the anti-skid strips on the first set of interplane struts, not the second, as this pic shows.
Also, the "crash" strut on the Russian F-Boats is connected behind the radiator (with a consequent lower attachment angle) rather than in front of the radiator as on this one. Finally, C-1 had a prominent set of cabane struts under the lower wing, highlighted here, which many of the F-Boats apparently did not. Insofar as cannister floats-vs-faired floats, I understand that such modifications were often added as new technology (float design, in this case) occurred, regardless of what was originally on the aircraft. Anyway, that's my guess.
Earl Finch (7/27/01): That angled crash strut was called a "Goodier Strut," but I don't know who or what Goodier was.
Joel Monka (8/7/01): I, too, would place them between the E and F series specifically, the Navy C series. Quoting from Bowers' Curtiss Aircraft 1907-1947:"The Navy bought five early flying boats from Curtiss and designated them Navy Type C. Numbering was in sequence of delivery, but the boats were not identical, ranging from one of the experimentals modified to near production standard (C-1/AB-1), to the stock F boat. On 8/30/13, the C-2 flew at Hammondsport under the complete control of a Sperry gyroscopic automatic pilot. The C-boats were redesignated as ABs with the same sequential numbers on 3/25/14."
This would put them after the Russian boats that had the anti-skid strips on the inner struts, and before the F series was standardized. This also fits a Curtiss pattern: redressing all their experimental aircraft and palming them off on the military as part of a later, more advanced series. I have pictures of the boats with the anti-skid strips on the inner struts under the designations A-2, OWL, E-1, AX-1. I sometimes have nightmares in which designations are changed each time the sparkplugs are replaced!
BTW, that August 1913 flight under autopilot is the first I'm aware of.
Bill Devins (10/5/01): The initial batch of Russian Curtiss 'boats were among the first Curtiss flying boats; the first was delivered by Curtiss himself and tested in Russia 9/16-11/5/13. In American Hydroaeroplanes in Russia 1912-17,Andrei Alexandrov (St Petersburg 1999) calls them F-boats, and photos show their flat hull bottoms, angular forward hull tops, inboard strut anti-skid panels, narrow tube ("skyrocket") tip floats, and aft-attached Goodier strut as described by Carl.
But there were two shipments to Russia of different F-boats; a few more were actually built there by PRTV. The two scans are F-boats of a second batch supplied to Russia in March 1914. They had been ordered the previous year, and on 12/19/13 Glenn Curtiss, while in Paris, informed I I Stakhovsky of the Imperial Russian Navy that he would be delivering this group with slight double-concave, rather than flat, planing bottoms.
Lt Kovedyaev is quoted as pilot of the pictured 'boat. Alexandrov identifies the aircraft as the Model F of 1914 with the following features: "tip-to-tip longeron wings [?], keeled bottoms, streamlined [rounded] hulls, side floats integrally connected with wingtips, radiators of another configuration, and so on." Both batches had upper wingtip extensions of clipped triangle shape. The wingtips are connected by a drag strut, not a wire as I originally thought, so the line in your colorized postcard photo is not as exaggerated as we thought. Note that these Russian examples have the anti-skid panels on the middle pairs of interplane struts, and, except for the additional fuel tank on the starboard side, look to me to be identical to the aircraft on the postcard. These are the aircraft I compared to the postcard in my original posting on the subject.
I suspect that no Curtiss flying boats had company model letters lower than "E". More confusion is caused by the various military designations, which is where all the "A"s and "C"s come from. Navy C-boats are almost assuredly some variant of Curtiss' Model F-boat.
Lew Casey (8/18/02): The "Goodier" strut was added after an early Curtiss pilot a Lt Goodier had the misfortune to have a crash and ended up with the engine in the middle of his back. According to him, he got up very early one Sunday morning and did a buzz job down the main street of town (I believe he said Hammondsport but the conversation was a little informal across a trestle table over lunch so I'm not certain), but forgot that telephone wires were laced across the street. He got tripped up by one or more of these wires and crashed in the middle of the street. He said he was trapped with a hot engine in the middle of his back until townspeople pulled it off him. The strut had several modifications including double struts on some later versions of the F boats.
Lew Casey (8/18/02): Until 1914 the F-boats were "in the development stage," as were most of the Curtiss machines of that period. In 1914 it became necessary to "standardize" in anticipation of military orders. The only E-boat was the first successful flying boat, which had the same wing panels as the land plane and hydroplane E aircraft. After that spars were continuous from hull to the tip, not separate sections as in the E. The triangular panels that seem to cause so much confusion were optional add-ons until the dimensions of the wing panels became standardized for the later 1914 model F-boats.
This is what makes aviation history fun, often frustrating, and always challenging. Lacking as I do most of the "fat" reference books (eg: Curtiss, Boeing, Martin, the Gunston goodies, Playboy, etc), I'm ever grateful for folks who dig into the dark corners for us.
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