The Curtiss “Jenny”: The Airplane That Introduced America To Aviation
Story and photos by Corey Beitler
When Golden Age Air Museum President Paul Dougherty Jr. brings the museum’s 1918 Curtiss JN-4D “Jenny” in for a landing during one of the museum’s public events, there is a collective sense of wonder from the spectators. With its huge wings and pedestrian pace, the “Jenny” looks like a large red bird gliding in for a landing. Closer inspection of the aircraft as it taxis into its parking spot reveals the wooden propeller, spoke wheels, and maze of bracing wires and wooden struts that hold the airplane together. As Paul Dougherty Jr. shuts down the engine and removes his flying cap and goggles, he waves to the crowd from the cockpit. As the spectators wave back and clap in appreciation of another excellent flight demonstration, few can appreciate that this 105-year-old aircraft is one of the few airworthy examples of its kind and is one of the most significant early airplanes in American aviation history.
The story of the Curtiss “Jenny” began in 1914. The U.S. Army was disgusted with its open-to-the-wind pusher training aircraft. Their performance was inferior to the aircraft being built in Europe, and the accident rate was high. The U.S. Army approached Glenn Curtiss and asked him to design and build a new training aircraft with a tractor propeller and an enclosed fuselage. Curtiss hired designer B. Douglas Thomas from the Sopwith Aviation Company in England to help him build the new aircraft.
The first production version of the JN or “Jenny” series was the JN-2, appearing for the first time in 1915. The biplane had large, equal span wings with ailerons controlled by a shoulder yoke in the rear cockpit. The eight JN-2s built were handed over to the 1st Aero Squadron of the Aviation Section of the U.S. Signal Corps. Unfortunately, the pilots of the 1st Aero Squadron soon found that the JN-2 lacked performance and was unsafe to fly. The new airplane was overweight, lacked stability, and had an oversensitive rudder. Shortly after they began flying the JN-2s, the 1st Aero Squadron wrecked two of them in crashes. The 1st Aero Squadron and its aircraft were grounded for safety reasons. Curtiss was ordered to make design changes to the JN-2 to improve its performance.
Curtiss redesigned the JN-2 and designated the new aircraft the JN-3. The improved JN-3 had wings of unequal span and ailerons on the top wing controlled by a wheel. A foot bar was added in the cockpit to control rudder movements. These changes to the flight controls improved the “Jenny” enough that it could be flown safely. In March 1916, eight JN-3s were deployed to Mexico and used an observation aircraft during the Pancho Villa Expedition.
After the success of the JN-3 variant of the “Jenny”, Curtiss once again made improvements to the design, the new “Jenny” being designated the JN-4. With World War I in full swing, both the U.S. Army and the Royal Flying Corps in Canada needed training aircraft and placed large production orders for the JN-4. In Canada, the name “Canuck” was adopted for the new aircraft. The Canadian “Canuck” also had some differences from the American “Jenny” including a more rounded rudder, differently shaped wings and elevators, and strut-connected ailerons on both wings. The JN-4D ended up being the definitive variant of the “Jenny”. Changes to this model included a control stick instead of a wheel, ailerons on the upper wing only, and curved cutouts on the inner trailing edges of all four wing panels to facilitate easier access to the cockpit.
The “Jenny’s” slow speed and gentle handling characteristics made it an ideal training aircraft. The tandem cockpit seating allowed a student pilot and instructor to fly together. The slow speed of the “Jenny” meant that if there was an accident, it usually was not fatal. The “Jenny” and the Canadian “Canuck” would play a pivotal role in pilot training for the Allies during World War I, with an estimated 95% of pilots completing at least some primary flight training in the aircraft. This training took place even in the harsh winter weather of Canada, with the “Jennies” wheels being replaced with skis to fly off snow-covered runways. In addition to its use as a trainer, the “Jenny” was also used as an air ambulance, its rear fuselage decking removed to accommodate a stretcher, one of the first times an aircraft was used in this role.
If there was any weak point in the “Jenny’s” design, it was the Curtiss-designed OX-5 V-8 engine that powered the aircraft. The 90-horsepower OX-5 engine was often described by “Jenny” pilots as a failure waiting to happen. The overhead valve system was open and exposed to the air, weather, bugs, and dirt. The engine was single-ignition, so one bad spark plug could cause an engine failure. The single-pushrod, arm-stirrup valve mechanism employed three springs per valve when spring manufacturing was not as exact as it is today.
The OX-5 engine’s greatest weakness was its cooling system. The engine was water-cooled and weighed in at a staggering 390 pounds. This excess weight contributed to the “Jenny” needing such a large wingspan and having a slow top speed and climb rate. The cooling system for the OX-5 was prone to overheating in the summer and leaking freezing water from the carburetor in the winter, stopping up the vents and sticking the valves. The water pump, located on top of the carburetor, leaked frequently. It was usually only a matter of time before the leaking water pump contaminated the gasoline supply.
As a result of the OX-5 engine’s unreliability, both the U.S. Army and the U.S. Navy began searching for a replacement engine that would fit the “Jenny’s” airframe with minimal modifications and provide improved horsepower and reliability. The search for a new engine resulted in a new advanced trainer variant of the “Jenny” being built, the JN-4H. The JN-4H was powered by a 150 or 180-horsepower Hispano-Suiza V-8 engine license-built by the Wright-Martin. This engine was lighter, more reliable, and produced almost twice the horsepower of the Curtiss OX-5. The final production version of the “Jenny” was the JN-6H, a variant for the U.S. Navy also powered by a Hispano-Suiza V-8 engine. These late-production models of the “Jenny” also had ailerons on the top and bottom wings. When production ended in the mid-1920s, Curtiss and several contractors had built over 6,500 Curtiss “Jennies”. The Curtiss “Jenny” remained in service with the U.S. Army as trainers until 1927.
After the end of World War I, thousands of Curtiss “Jenny” aircraft ended up on the civilian market, being sold as surplus. In anticipation of offering surplus “Jennies” to the civilian market, Glenn Curtiss and his company bought back unneeded production aircraft from the U.S. Army and began offering them for sale at $4,000 each and surplus OX-5 engines for $1,000 each. Curtiss aggressively marketed the surplus aircraft and engines, and their applications on the civilian market. Unfortunately, the thousands of surplus “Jennies” on the market brought the price of the aircraft and engines down to as little as $600 for a “Jenny” and $50 for an OX-5 engine, both brand new in their shipping crates. This was a financial disaster for Curtiss, who had spent almost $20 million buying back “Jennies” from the U.S. Army only to have to sell them at a loss when the market became flooded with surplus aircraft.
These pilots and their “Jennies” began the barnstorming era in the United States. With no civil aviation regulations in place, the pilots were free to fly wherever and whenever they wanted. The pilots lived in their airplanes, wearing only the clothes on their backs and carrying all their possessions in their “Jennies”. Many of these pilots were World War I veterans or those who had completed fight training but never served in combat.
At first, the barnstorming pilots traveled from town to town, offering rides at $25 a hop. They marketed themselves by telling tales, often fantasy, of their exploits in the war. Farmers who allowed the pilots to use their fields as landing strips were offered rides for free. Kids from the town who assisted the pilots by organizing the line for rides also got free rides. For many people in rural parts of the United States, a barnstorming pilot visiting their town with a Curtiss “Jenny” was the first time they saw an airplane or rode in one. In the first years of the barnstorming era, some pilots made over $10,000 a year. By 1925, the market had become oversaturated with barnstorming pilots offering rides, and the price for a ride had stabilized to about $5. The barnstorming pilots were now lucky to make $5,000 a year.
As the ride market became more competitive, the barnstormers and their “Jennies” formed air circuses and flew in groups. These air circuses visited state, town, and county fairs and carnivals around the nation, performing airshows, often with multiple aircraft flying at once. The pilots performed various aerobatic maneuvers and stunts with their aircraft. Aerobatics and stunts included loops, rolls, landing on one wheel, and parachuting from the airplane. As the air circuses grew in popularity, the stunts grew more elaborate to include wing-walking, plane-to-automobile transfers, plane-to-plane transfers, and on occasion, deliberately crashing an airplane. The air circuses drew thousands of spectators, some coming just to see if someone was unfortunate enough to get killed during the stunts.
In many ways, the old Curtiss “Jennies” were the perfect aircraft for the barnstormers. The OX-5 engine, though unreliable and prone to failure, was easily repairable, and many automobile and marine engine parts were compatible with the engine. If a bracing wire was snagged landing in a farm field and snapped, wire from a farmer’s fence could be used as a temporary repair. The fabric wings could be patched with simple fabric and dope. The wings, with all those struts and bracing wires, combined with the slow speed and stable flight characteristics of the “Jenny”, made the aircraft a perfect platform for wing-walking and plane-to-plane and car-to-plane transfers during flying circus airshows. Aircraft and engines wrecked in accidents or mishaps were easily replaced with new ones bought at surplus for reasonable prices.
Unfortunately, all good things come to an end. As the barnstorming continued into the late 1920s, the number of accidents grew at an alarming rate. Many of these accidents were due to aerobatic maneuvers being performed too low, but a troubling number of accidents were attributed to the “Jennies” experiencing structural failures. Although parachutists falling to their deaths or “Jennies” crashing sometimes thrilled the crowd at a flying circus airshow, the federal government thought otherwise.
In 1927, the federal government published the first civil air regulations in the United States. These regulations essentially ended the barnstorming era in the United States. The pilots could no longer fly and do whatever they wished. The new regulations also established airworthiness requirements for civil aircraft. Many of the “Jennies” were so worn out that they failed to meet the new airworthiness standards. Charles Lindbergh’s “Jenny” was so worn out and tattered from barnstorming that when he joined the Army Air Service he was ordered to remove the aircraft from the airfield. By the late 1920s, the barnstorming era was over, and most of the “Jennies” were scrapped.
Of the over 6,000 “Jennies” built, very few survive today. The barnstorming era took its toll on the wooden and fabric-covered “Jenny”, and most of the airframes were so worn out that they were beyond saving. Most of the surviving “Jennies” are in museums. Less than a dozen “Jennies” are in airworthy condition, and only a handful of these airworthy examples fly regularly. This article features photographs of two of the surviving “Jennies”, which are probably the most active airworthy examples in the world, the Golden Age Air Museum’s 1918 JN-4D and the Old Rhinebeck Aerodrome’s 1917 JN-4H.
The bright red “Jenny” featured in photographs in this article is a 1918 Curtiss JN-4D model. This “Jenny” is owned by the Golden Age Air Museum in Bethel, Pennsylvania. The museum acquired the “Jenny” in 2001 and began a lengthy process to restore it to its original condition, including the aircraft’s rare original OX-5 engine. The “Jenny” flew for the first time after its restoration in 2009, and since that time, has been flying regularly at the museum during special events when wind and field conditions allow. The JN-4D is painted in the colors of famous barnstormer and Hollywood pilot Earl S. Daugherty from Long Beach, California. In 2017, Golden Age Air Museum President Paul Dougherty Jr.’s daughter, Caroline, soloed for the first time on her 16th birthday in the “Jenny”, an aircraft that is her father’s and the museum’s pride and joy.
The second “Jenny” featured in photographs in this article is the 1917 JN-4H owned by the Old Rhinebeck Aerodrome in Rhinebeck, New York. Old Rhinebeck Aerodrome museum founder Cole Palen received this aircraft, missing parts and its engine, in 1957. The “Jenny” was discovered to be a rare Hispano-Suiza-powered example of the aircraft. Eventually, some of the missing parts turned up, and Palen was able to acquire a 180-horsepower Hispano-Suiza engine from the Franklin Institute to use in the “Jenny”. The restoration of the “Jenny” began in 1967, with parts of several other JN-4s used during the rebuild to restore the aircraft to flying condition. After flying at the Aerodrome from 1969 to 1998, the “Jenny” was once again completely restored by Old Rhinebeck Aerodrome master mechanic and pilot Ken Cassens. The “Jenny” returned to the skies of Old Rhinebeck Aerodrome in 2001 and has flown in weekend airshows at the museum ever since. The JN-4H is restored in the color scheme of a training aircraft used by the U.S. Navy at Naval Air Station Pensacola in Florida in the early 1920s.
The Curtiss “Jenny” performed admirably as a trainer and was responsible for training thousands of pilots during World War I, but the role it had in postwar aviation in the United States was more significant. Throughout the 1920s, the “Jenny” introduced thousands of Americans across the country to aviation, either through a barnstorming pilot giving rides at a local farm, a flying circus performing at a county fair, or a pilot delivering airmail to a town. The “Jenny’s” ease of operation, affordability, and ruggedness helped to make it one of the most successful early aircraft in American aviation history.
As Ken Cassens takes Old Rhinebeck Aerodrome’s 1917 JN-4H “Jenny” up for a flight during a weekend airshow, the spectators stare into the sky as an airplane over 100 years old gracefully dances with the clouds and the wind. They are captivated by the sound of its engine, the maze of struts and wires holding the wings together, and the pilot wearing his leather cap, flying goggles, and scarf, just like many Americans were when the barnstormer came to visit their town in a “Jenny”.