Like the United States Army's air service of the early 20th century, the United States Navy (USN) air power managed a humble beginning through a series of experimental aeroplanes used to prove certain concepts of naval service viable. The Curtiss A-1 "Triad" became the United States Navy's first-ever aircraft when ordered on May 8th, 1911 and this platform was developed as a true "amphibian" - able to take-off and land from both water and airfields respectively thanks to a floatplane pontoon arrangement for the former action and a retractable wheeled undercarriage for the latter. The "Triad" name stemmed from this versatility for the machine operated through all three facets - air, land, and sea. While not used in a frontline, combat-minded operational manner by the USN, the A-1 still held tremendous value in a developmental sense concerning testing, doctrine, and pilot training. The Triad saw a first flight on February 25th, 1911 and carried the company model designation of "Model E".
Experimentation with such over-water aircraft like the Triad is what piqued the interest of USN authorities in the early years of flight. Glen Curtiss (1878-1930), founder of his famous Curtiss Aeroplane Company, showcased to the Navy the value of his floatplane designs when he landed an aircraft on the water alongside a US Navy vessel. The vessel then used its onboard crane to recover the aircraft - giving rise to the concept of seaplane observation platforms that was carried even into World War 2 (1939-1945) for over-the-horizon scout work. The USN moved on purchasing some fourteen A-1s and variants included the E-4 and E-8 with differences laying in the type and output of engine in play (the "E-4" had a 4-cylinder engine, the "E-8" an 8-cylinder engine, and the "E-8-75" an engine of 75 horsepower output).
The A-1 provided the important groundwork for US naval aviation and introduced flight to the first generations of American naval airmen. Despite its rickety appearance, the Triad was consistent with design and construction philosophy of the time. A biplane wing arrangement was used with parallel struts for support. The pontoon assembly was installed under the aircraft with bicycle-style landing wheels straddling the fixture. The pilot (and one other passenger) sat at the front of the wing arrangement with a horizontal plane fitted just ahead of his position. An automobile-style steering wheel was used for primary controlling. The powerplant was fitted aft of the pilot and between the upper and lower wing structures, the engine operating in a "pusher" arrangement and driving a two-bladed wooden propeller facing the rear of the aircraft. Thin strut work and cabling connected the mass of the aircraft to several more control and stability surfaces found at the rear of the aircraft.
The Triad was used in the USN's first-ever (semi-successful) catapult launch test and made the first water landing at night. The platform was also used for early tests in surface-to-air communications and overland endurance ventures. The A-1 series continued in this test-minded role until its value had been played out and all-new technologies rendered the design obsolete. By the time of World War 1 (1914-1918), a new generation of biplane fighters arose to take the aviation mantle from these early - and usually lethal - pioneering efforts.
A replica of the A-1 Triad hangs in the lobby of the Naval Aviation Museum in Pensacola, Florida, USA while an original (flyable) example is preserved at the EAA AirVenture Museum of Oshkosh, Wisconsin, USA.