The possibility of combining the ability to fly and the capacity of a marine vessel had been around even before the Wright Brothers flew their Flyer aircraft at Kitty Hawk, N.C. Serious experimentation on this concept began around 1897, but it was not until 1898 that the first attempt to fly a boat was made. Wilhelm Kress, an Austrian, began construction in 1898 on what would eventually be considered to be the first flying boat craft. It was a simple design. A tandem tri-plane frame fitted with two massive floats. Its power plant was a single Daimler 30hp engine, driving two broad propellers. The craft was first tested in October 1901 on a reservoir near Tullnerbach, Austria; it did not make it to the air. Problems with the floats and the aerodynamics of the fuselage doomed the aircraft. Undaunted, Kress pressed on with his ideas, and in 1903, was ready to make another attempt, but by this time the lack of interest on the project and his financial situation forced him to abandon the idea.
Experimentation with flying boats gained a renew interest with the news of the first ever powered controlled flight by the Wright Brothers in Kitty Hawk, NC. On the other side of the Atlantic, the Vosin Brothers, Charles and Gabriel; after receiving the news; promptly commenced work on their own flying boat design. Their hard work finally payoff when on June 6, 1905; Gabriel became the first man to take-off and land a plane on a body of water. Although the aircraft was used as a glider, which required an external power source to propel it into the air, the craft did prove the feasibility of the concept. The next aircraft design by the Vosin Brothers was destined to be a groundbreaker. Named the Bleriot III after the individual who requested the craft’s design and production; this new concept was made out of two wing structures in an ellipse form placed on tandems. The complete airframe floated on water by function of skids surrounded by sealed tubes. On a clear morning in May 1906, the Bleriot III was ready for the first of a series of tests intended to prove the aircraft’s airworthiness. In each test, the aircraft performed badly, leading the Brothers to suspend further collaboration with Bleriot on this particular project. Bleriot, unmoved by the Brother’s decision, tried himself to build a workable seaplane. In late 1906 he was ready for another set of trials, and again, the results were less than promising.
In the other side of the Atlantic, the United States military was quickly to recognize the potential of a sea-based plane. During the month of November 1908, an American aviation pioneer by the name of Glenn H. Curtiss performed an airframe modification to his already successful airplane, the June Bug. He removed the wheel undercarriage and replaced with a tandem of wooden floats covered by canvas. The new plane, named Loon, was first tested in late November 1908. Initial test results were somewhat promising. The Loon was able to lift itself from the water but with a relatively slow speed of 25mph; the Loon was not able to accelerate enough to gain air stability. The hydrodynamic drag caused by the massive floats was too much for the engine to propel the aircraft above that speed. Nevertheless, encourage by the test results on the Loon, Curtiss expanded his research. He followed the Loon with the modification of the Curtiss Model D for water duties. In this configuration, the Model D was fitted with a single canoe decked over with canvas. This configuration presented Curtiss with the same problems as before: hydrodynamic drag. But as with the Loon, the results were promising enough to encourage Curtiss to invest more resources on the project.
What history had in store next for Curtiss was truly groundbreaking. In early 1910, the U.S. Navy, after being refused by the Wright Brothers, asked the newly formed Curtiss Company to build an aircraft capable of taking-off from a platform installed on a warship. On November 14th, 1910, Eugene Ely, a Curtiss Company test pilot; successfully took-off from a provisional platform installed on the USS Birmingham near Hampton Roads, Virginia. A series of take-off flights followed, culminated with a successful landing of a Curtiss built plane on a provisional platform installed on the USS Pennsylvania in January 1911. However impressive these tests had been, the Navy’s top brass was not overly impressed. They focussed their attention on the development of an aircraft that could be launched and recovered by a battleship in times of conflict.
For the next phase of story of the development of the seaplane as a realistic alternative, one needs to look at a young French engineer. Henri Fabre, was born in Marseille in 1882 and since his early teen years he devoted his time in the study of aerodynamic forces. He experimented with kites and aircraft models to look at how aerodynamic characteristics of airframes and wings are affected by wind flow. He also studied the effects of hydrodynamic forces on a structure. Thus giving him an inside look at the forces that affect air travel. His first attempt at building a seaplane was a simple design. A conventional monoplane was modified to carry two floats mounted under the wing structure in a catamaran-type configuration. A small float was added to the tail section of the fuselage. The aircraft was powered by three Anzani engines capable of generating a 12hp each. They drove a single tractor propeller. The first series of test occurred in July 1908 and achieve little, if any, positive results. Reasons for the failure were never properly explained, but most aviation historians place the blame on the weight of the floats.
For his next design, Fabre chose a canard layout. On this configuration, the main wing structure was placed at the rear of the fuselage, with two small canard wings near the front. The idea behind the concept is simple. The canards, Fabre thought, would give the aircraft a long sought longitudinal stability. His first test of this new concept was performed on Christmas eve, 1909. The aircraft, powered by a single Anzani engine, took-off for a brief time, but ultimate fell hard to the water due to its underpowered characteristics. The relative short flight did show that the canard configuration could provide air control to the aircraft once airborne. Realizing that the aerodynamics was sound, Fabre promptly went out to find a more powerful engine to propel his new design. After searching hard for a power plant, a friend recommended to Fabre the Gnome’s Omega 7 cylinder rotary engine. The Omega was capable of generating 50 hp and its weight was a respectable 165 lb. With the engine now in hand, Fabre began the development of a new seaplane. As was in the case before, the new plane was centered on the canard wing configuration. What varied from previous designs was the massive wing area, now composing 258 sq ft. The Omega engine was installed at the end of the aft in the main frame. It was located in this area because Fabre calculated that a pusher-type system would better achieve the necessary lift-power ratio needed to propel the aircraft into a stable and controlled flight.
Testing on this new concept commenced in early March 1910. Immediately, taxing testing showed the aircraft’s sound aerodynamic characteristics. On the morning of March 11th, 1910 the Hydravion, the new name for the aircraft, was ready to take to the air for the first time. It was towed to the middle of the Etang de Berre. With nothing more that calm water surrounding the test site, the Omega engine was brought to life. Immediately, the aircraft responded to the Omega and the Hydravion achieved substantial speed in the water. After more taxi testing, the Hydroavion took to the air on that same day. In series of relative short flights, the Hydroavion once again demonstrated its ability to achieve flight status. Fabre continued his experiments into the spring of 1910. All successful flights, but on May 18th, 1910, with Fabre himself at the controls, the Hydroavion lost control and fell into the water from an altitude of approximately 130 ft. The crash did little to alter the course of the programme, the Hydroavion was recovered and repaired, but it did affect Fabre deeply, it is said that he never flew another aircraft after the incident.
Back in America, Glenn Curtiss was observing with interest the progress made by Fabre. He even took time to visit Fabre in late 1910. By this time, Curtiss had moved his winter flying operations to North Island in San Diego, CA. There, the weather was more conduits for sea-flight experimentation. After many months of research, Curtiss, now with the assistance of Lieutenant Ellyson, a brilliant U.S. Navy engineer that specialized in physics and mechanics; determined that the main obstacle to achieving flight status on a seaplane was the shape of the floats. They researched many forms of floats, eventually settling on a configuration first suggested by Fabre: the use of a flat bottom with a positive trim angle. On January 26th, 1911, after years of extensive research and development, Curtiss saw his dream come true when his new seaplane design, a bigger canoe configuration airframe fitted with the new floats; took to the air. The test result was more than promising; they inspired Curtiss to redouble his efforts. They did extensive modifications on the canoe frame as well as in the float configuration to make them flight operational.
Curtiss, now embolden by the test results, decided to call his old friend, Captain Charles F. Pond of the USS Pennsylvania. The same ship platform that Curtiss used for his ground breaking experiments; and asked him if he would mind that Curtiss made a ship call on the Pennsylvania, now anchored off San Diego Bay. Pond, who was at the time one of the few true advocates of naval aviation, was ecstatic about the possibility and gave Curtiss the go ahead order. On February 1911, Curtiss took-off from his base at North Island and proceeded to land at the side of the Pennsylvania. After arriving, the ship used its boat crane to lift up the aircraft to the deck, the same concept was used to put the plane back in the water. This amazing exercise performed by Curtiss was the first step in the operational development of the seaplane by the U.S. Navy. After the demonstration, Curtiss went on to develop several series of flying boats in 1912, some of them served in the Great War two years later. In France, Fabre recognized Curtiss’s achievements and promptly proclaimed him as the father of the operational seaplane. Fabre, sensing that there was not much new ground to break at that time, decided to abandon major experimentation with seaplanes. That did not mean that Fabre stopped completely his association with flying boats. He supplied floats pieces to many countries during the years up to the Great War, and during the conflict, he was placed in charge of the vaunted Saint Raphael Naval Aviation Depot.
The colorful story of the birth of the seaplane is actually the story of two dedicated and visionary men, Glenn Curtiss and Henri Fabre. The seaplane was born out of their collective dedication and vision. Their need to prove a new and untested concept improved our understanding of how aerodynamic forces affect a sea-based flying platform. We are indeed grateful for their compliments and contributions to the development of the airplane in an era dominated by skeptics and doubters. They truly gave birth to the seaplane.
– Raul Colon