Curtiss JN4D “Jenny”
In many ways, the Curtiss Jenny could be considered the Model T of the skies. Roughly a contemporary of Ford’s famous auto, the Jenny would eventually help to establish the practical reality of American aviation.
The Jenny was the first aircraft purchased in quantity by the American military, and consequently was the first mass-produced American aircraft. Used to train over ninety percent of American pilots during WW I, it played a key role at the beginning of what would become the most powerful air force on Earth.
Before 1927, the Jenny would also be the first aircraft many American’s would ever see close up, let alone fly in. Post-war surplus Jennies, bought by enterprising barnstormers, flew across rural America to sell rides, thrill spectators, and inspire young pilots-to-be. It would have been rare indeed to find an American pilot that had not flown in the Jenny. Charles Lindbergh’s first aircraft was a Jenny bought in 1923 for $500.
The Jenny began as a combination of two aircraft: the model J, designed by the British engineer, B. Douglas Thomas, under contract to Glenn Curtiss; and the model N, which was a similar design under parallel development. Both were developed as two-seat tractor aircraft, powered by the new Curtiss OX-5 engine.
With the best features of the J and N models combined, the American Army began ordering Jennies in December 1914, under the official designation JN2. The “Jenny” nickname followed, derived from the JN designation prefix.
First used by the Army Signal Corps in 1916 for tactical operations in Mexico against Pancho Villa, the Jenny design was subsequently upgraded and given the designation JN3.
The British Royal Navy ordered the upgraded Jenny for use as a primary trainer, and Curtiss opened another factory to meet the demand. Further design changes resulted in the JN4 and JN4-A models, which were sold to the U.S. Air Service, the U.S. Navy, the British Royal Flying Corp and the British Navy.
Design changes continued, resulting in several JN designations: a Canadian licensed built JN-4 known as the “Canuk”, a JN4-B, which had some success in the civilian market, and one experimental JN4-C. In 1917, one month after America entered WW I, the definitive version of the Jenny was introduced as the JN4-D.
Wartime demand totally overwhelmed Curtiss’ production capacity. Along with Canadian production, six other American companies were contracted to share the load: Fowler Airplane Corporation, Liberty Iron Works, Springfield Aircraft Corporation, St. Louis Aircraft Corporation, U.S. Aircraft Corporation, and Howell & Lesser.
During the Great War, Jenny’s were modified in numerous ways to perform various roles, some resulting in further designations such as: N-9, JN4-H, JN4-HT, and JN4-HB. The JN4-H models featured 150 HP Hispano-Suiza engines replacing the 90 HP OX-5 (a welcome upgrade for the seriously under-powered Jenny). While designed and used primarily as a trainer, the Jenny also saw service as a reconnaissance, bomber, ground attack, seaplane, and fighter aircraft.
Flight instruction in the Jenny was completed in about 50 hours over the course of six to eight weeks. Training began in the front seat, with between four to 10 hours of dual seat instruction (with the instructor sitting in back screaming directions over the roar of the engine). Soloing moved the student into the back seat – the Jenny was always soloed from the back. After 24 hours of flying solo, followed by 16 hours cross-country, training was complete.
In its intended role as a primary trainer, the JN4-D is said to have performed well (although it also has been said, “ If you can fly the Jenny, you can fly anything!”). It had a maximum speed of around 75 mph, and cruised about 10 mph less, with a landing speed of about 40 mph. It had relatively sluggish handling characteristics, with a virtually non-existent rate of climb (a blistering 200 feet per minute). Stall recovery was tricky and used up a great deal of altitude, and it’s OX-5 engine was often rough-running and unreliable. Consequently, about 20% of all Jenny’s built were destroyed during flight training.
More than 6,000 Jenny’s were ultimately produced, but at war’s end, military orders were abruptly terminated. However, public demand for surplus aircraft was high. At thirteen cents on the dollar, Curtiss bought $20 million worth of Jennies back from the U.S. government, refurbished, and resold them.
Jennies, along with a host of associated after-market parts and services, flooded a lucrative civil market. Along with the barnstormers roaming the countryside, Jennies found their way into several industries, including transportation, airmail, forest service, surveying, and many others. American civil aviation boomed.
Up through the early 1920s, Jennies became extremely popular and widely available, especially when air services began selling surplus Jennies. Private owners also sold Jennies amongst themselves, sometimes for as little as $50. However, around 1925 as improved aircraft designs became available, the popularity of the Jenny began to decline.
In 1926, the Air Commerce Act was passed, and the era of the Curtiss Jenny drew to a close. The Jenny in commercial use simply could not meet safety requirements. For a time, some continued to fly under grandfather clauses, but annual inspections eventually grounded the remaining aircraft.
This aircraft researched by EAA volunteer Bob Mueller