Updated: Apr 10, 2022
The first contract issued by the United States Navy for the production of aircraft was issued by telegram on this day in aviation history in 1916. Aircraft manufacturer Glenn H Curtiss received the telegram to supply 30 N-9 Hydro aeroplanes from the US Navy Bureau of Construction and Repair. The N-9 would become the most popular training aircraft for the US Navy during the First World War.
The well-known Curtiss JN Jenny series of aircraft was based on the N series of aircraft, the N series itself was based on the Curtiss model J. The Curtiss N-9 was the most popular variant of the Curtiss N series. To keep the N-9 afloat it was equipped with a single float under the fuselage and a small float under each wing. Structural and Aerodynamic changes were incorporated in the Curtiss N-9 to support the extra weight and structural loading of the aircraft because of the added floats. These modifications were designed with the aid of wind tunnel data. Making it the first US Navy aircraft using wind tunnel data. Changes compared to the standard Curtiss N were:
10’ (3 meters) wingspan increase
Vertical & horizontal tail surfaces enlarged
Stabilizing fins installed on the upper wing
Initially and Curtiss OXX-6 Engine (V8 water-cooled engine, 100 hp)
Besides the order for the US Navy, Curtiss also received an order for 14 Curtiss N-9 aircraft for the seaplane operation of the US Army. Soon it became apparent that the aircraft was underpowered and the Curtiss OXX-6 engine was replaced by a license-built 150 Horsepower Hispano-Suiza engine. Aircraft fitted with this engine were identified as an N-9H.
The Hispano-Suiza aircraft engine
A total of 560 N-9 were built during the 1st World War, after the war, another 50 were built from spares still available.
A fun fact of the N-9 aircraft is that at the time it was widely believed the aircraft could not be looped. United States Marine Corps pilot, Francis Thomas Evans, Sr., didn’t agree with that belief and decided to proof the world he was right. On the 13th of February 1917, he attempted to loop an N-9 over the Gulf of Mexico. After 3 failed attempts (stalling before reaching the apex of to loop and entering a spin each time!) he succeeded on his 4th. To recover from the spins on the first 3 attempts he released the backpressure on the stick and applying aggressive rudder opposite to the spin direction. A technique still used for spin recovery to this day! Lacking witnesses to his successful loop he flew to Naval Air Station Pensacola and repeated looped the aircraft in the skies over the Naval Air Station.
N-9’s remained in service with the US Navy until 1929 when they were replaced by modern trainers.
General characteristics of the Curtiss N-9H
Length: 30 ft 10 in (9.40 m)
Wingspan: 53 ft 4 in (16.26 m)
Height: 10 ft 11 in (3.33 m)
Wing area: 496 sq ft (46.1 m2)
Empty weight: 2,140 lb (971 kg)
Gross weight: 2,750 lb (1,247 kg)
Powerplant: 1 × Wright-Hisso A V-8 water-cooled piston engine, 150 hp (110 kW)
Propellers: 2-bladed fixed-pitch wooden propeller
Maximum speed: 78 mph (126 km/h, 68 kn)
Service ceiling: 6,600 ft (2,000 m)
Time to altitude: 3,240 ft (990 m) in 10 minutes