In December 1910, Ellyson was ordered by Captain
Washington I. Chambers, the Navy's first director of naval aviation, to North Island, San Diego, California for instruction in aviation under
Glenn Curtiss. While at an Aero Club show on 28 January 1911 near the flight school, Ellyson took off in a Curtiss "grass cutter" plane to become the first Naval aviator. With a blocked throttle, this ground plane was not supposed to fly, and Ellyson was not proficient enough to fly. He slewed off left, cracking up the plane somewhat by making a wing-first landing. However, Ellyson was not injured and from then on he was considered to have made his first flight on this date. He also cooperated with Curtiss in the design of a
pontoon for aircraft, and after Curtiss' first flight on 27 January 1911, Ellyson went up with Curtiss in February to become the first passenger to go aloft in a floatplane. Later that month, he participated in experiments demonstrating the potential use of floatplanes from ships, when the aircraft was hoisted on board and subsequently lowered to the water for its return flight to North Island. LT Ellyson became first aviator in history to qualify as a pilot according to Federation Aeronautique Internationale (FAI) standards in a flight over water. In the presence of a committee of the Aero Club of America, he was required to fly five figure eights around two flags buoyed 1500 feet apart and land within 150 feet of an established mark. This course had to be completed twice. When Ellyson qualified, he landed directly alongside his mark, a white flag buoyed by a bottle. His second landing was within ten feet of his first. The test also required the prospective aviator to climb to a minimum altitude of 150 ft (officially 50 meters). Ellyson made this twice on his test. On September 7, 1911, LT Ellyson, in the Navy model A-1 Triad, slid down 150 ft on a wire cable at
Hammondsport, New York from a platform 25 ft high, and was safely launched out over
Keuka Lake. From the time Ellyson began instruction in aviation until 29 April 1913, he devoted all of his time to active flying and experimental work in aviation. This included the establishment of Naval Aviation Camps at
Annapolis in September 1911 when, with then-Lieutenant
John H. Towers, he flew an aircraft from Annapolis to
Milford Haven, Virginia, a nonstop distance record for float planes. ==World War I service==