Junkers J2 Single-Seat Monoplane Fighter Prototype
Developed from the promising J1, the Junkers J2 became the first military fighter of all-metal design anywhere in the world when it first-flew in July of 1916.
Entry last updated on 12/2/2016; Authored by Staff Writer; Content ©www.MilitaryFactory.com
Service Year: 1916
Type: Single-Seat Monoplane Fighter Prototype
National Origin: Imperial Germany
Manufacturer(s): Junkers & Company - German Empire
Total Units Built: 6
The first purpose-built, all-metal military monoplane fighter aircraft was the Junkers "J2" prototype of 1916. Only six were constructed but the series nevertheless ushered in a new era of aircraft design concerning combat-minded platforms. Unfortunately for the type, it arrived at a time when fabric-over-wood biplanes and triplanes were still the accepted comfortable norm and thusly a very limited number of Hugo Junker's designs were actually adopted for military service in World War 1 (1914-1918) (the metal-skinned CL.I of 1917 saw 51 examples produced for the German Empire).
Hugo Junkers was championing the idea of an all-metal aircraft even before World War 1 but the conflict allowed the concept to gestate at a much quicker pace. Work resulted in the J1 monoplane which went to the air for the first time in December of 1915. Purely experimental, the J1 set the stage for the J2 that followed - a dedicated fighter mount for the German air services.
The success of the J1 in testing allowed the J2 to be funded by the research arm of the German air force and six all-metal aircraft were contracted for from Junkers & Company for the over-battlefield role of fighter. This type of aircraft required good handling and performance as well as reliability and robustness making up a very stable gunnery platform - no small feat for any one aircraft design during wartime. The engine of choice became the Mercedes D.II inline which outputted 120 horsepower and was able to drive the J1 prototype to speeds of 110 miles per hour (the German air force required the new aircraft to exceed at least 90mph). Armament would be 1 x 7.92mm Spandau IMG 08 series machine gun synchronized to fire through the spinning propeller blades.
The resulting design was a sleek offering with its rounded-edge fuselage. The monoplane wings were slim appendages fitted to the sides of the fuselage and braced internally. The tail unit was traditional (though the rudder was an all-moving surface) as was the undercarriage. The engine sat at the nose driving a two-bladed propeller unit and the pilot was aft of this installation in an open-air cockpit. Because of the monoplane wings in play, views out-of-the-cockpit were to be rather good when compared to competing biplane and triplane types seen in the war. A raised fuselage spine and added roll bar protected the pilots head and neck from the aircraft accidentally rolling over onto its back. The engine fit was nearly all-enclosed in the fuselage frontal section - unlike the exposed form of the earlier J1.
As impressive and revolutionary as the J1 was when debuted, the J2 was moreso. A first example was completed in early-1916 and this led to a first-flight recorded on July 11th of that year amidst official structural evaluations. On the whole, the aircraft exhibited strong maneuverability and turning and was stable overall - though its largely metal construction restricted rate-of-climb which was a crucial quality of dogfighting in World War 1. Maximum speed reached during this time was 112 miles per hour.
The project would never overcome its weight deficiency and one test pilot was lost in a crash during September 1916. This event ended formal government-level support for the aircraft. In the upcoming J3 design, lighter weight "duralumin" replaced the electrical sheet steel used in the J1 and J2 prototypes.
In testing (with a Mercedes D.III engine of 160 horsepower), the J2 was rated with a maximum speed of 124 miles per hour coupled with an operational range out to 382 miles and a service ceiling of 14,760 feet.