The Kettering Bug was an experimental unmanned aerial torpedo, a forerunner of present-day

cruise missile A cruise missile is a guided missile used against terrestrial or naval targets that remains in the atmosphere and flies the major portion of its flight path at approximately constant speed. Cruise missiles are designed to deliver a large warhe ...

s. It was capable of striking ground targets up to from its launch point, while traveling at speeds of . The Bug's costly design and operation inspired Dr. Henry W. Walden to create a rocket that would allow a pilot to control the rocket after launch with the use of radio waves. The British radio controlled weapons of 1917 were secret at this time. These designs were forerunners of modern-day missiles.

Development

During

World War I World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fightin ...

, the United States Army aircraft board asked

Charles Kettering Charles Franklin Kettering (August 29, 1876 – November 25, 1958) sometimes known as Charles Fredrick Kettering was an American inventor, engineer, businessman, and the holder of 186 patents. For the list of patents issued to Kettering, see, Le ...

Dayton, Ohio Dayton () is the sixth-largest city in the U.S. state of Ohio and the county seat of Montgomery County. A small part of the city extends into Greene County. The 2020 U.S. census estimate put the city population at 137,644, while Greater Day ...

to design an unmanned "flying MACHINE" which could hit a target at a range of . Kettering's design, formally called the Kettering Aerial Torpedo but later known as the Kettering Bug, was built by the

Dayton-Wright Airplane Company The Dayton-Wright Company was formed in 1917, on the declaration of war between the United States and Germany, by a group of Ohio investors that included Charles F. Kettering and Edward A. Deeds of Dayton Engineering Laboratories Company ( DELCO) ...

. Orville Wright acted as an aeronautical consultant on the project, while

Elmer Ambrose Sperry Elmer Ambrose Sperry Sr. (October 12, 1860 – June 16, 1930) was an American inventor and entrepreneur, most famous for construction, two years after Hermann Anschütz-Kaempfe, of the gyrocompass and as founder of the Sperry Gyroscope Company. H ...

designed the control and guidance system. A piloted development aircraft was built as the

Dayton-Wright Bug The Kettering Bug was an experimental unmanned aerial torpedo, a forerunner of present-day cruise missiles. It was capable of striking ground targets up to from its launch point, while traveling at speeds of . The Bug's costly design and operat ...

. The aircraft was powered by a

two-stroke A two-stroke (or two-stroke cycle) engine is a type of internal combustion engine that completes a Thermodynamic power cycle, power cycle with two strokes (up and down movements) of the piston during one power cycle, this power cycle being comple ...

V4 DePalma engine. The engine was mass-produced by the

Ford Motor Company Ford Motor Company (commonly known as Ford) is an American multinational automobile manufacturer headquartered in Dearborn, Michigan, United States. It was founded by Henry Ford and incorporated on June 16, 1903. The company sells automobi ...

for about $40 each. The fuselage was constructed of wood laminates and papier-mâché, while the wings were made of cardboard. The "Bug" could fly at a speed of . The total cost of each Bug was $400.Cornelisse, Diana G. ''Splendid Vision, Unswerving Purpose: Developing Air Power for the United States Air Force During the First Century of Powered Flight''. Wright-Patterson Air Force Base, Ohio: U.S. Air Force Publications, 2002. . The Bug was launched using a dolly-and-track system, similar to the method used by the Wright Brothers when they made their first powered flights in 1903. Once launched, a small onboard

gyroscope A gyroscope (from Ancient Greek γῦρος ''gŷros'', "round" and σκοπέω ''skopéō'', "to look") is a device used for measuring or maintaining orientation and angular velocity. It is a spinning wheel or disc in which the axis of rota ...

guided the aircraft to its destination. The control system used a pneumatic/vacuum system, an electric system and an aneroid barometer/altimeter. To ensure the Bug hit its target, a mechanical system was devised that would track the aircraft's distance flown. Before takeoff, technicians determined the distance to be traveled relative to the

air The atmosphere of Earth is the layer of gases, known collectively as air, retained by Earth's gravity that surrounds the planet and forms its planetary atmosphere. The atmosphere of Earth protects life on Earth by creating pressure allowing for ...

, taking into account wind speed and direction along the flight path. This was used to calculate the total number of engine revolutions needed for the Bug to reach its destination. When a total revolution counter reached this value a cam dropped down which shut off the engine and retracted the bolts attaching the wings, which fell off. The Bug began a ballistic trajectory into the target; the impact detonated the payload of of explosives.

Flight test

The prototype Bug was completed and delivered to the Aviation Section of the

U.S. Army Signal Corps ) , colors = Orange and white , colors_label = Corps colors , march = , mascot = , equipment = , equipment_label = ...

in 1918, near the end of

. The first flight on October 2, 1918 was a failure: the plane climbed too steeply after takeoff, stalled and crashed. Subsequent flights were successful, and the aircraft was demonstrated to Army personnel at Dayton. "The Kettering Bug had 2 successes on 6 attempts at Dayton, 1 of 4 at Amityville, and 4 of 14 at Carlstrom." Despite some successes during initial testing, the "Bug" was never used in combat. Officials worried about their reliability when carrying explosives over Allied troops. By the time the War ended about 45 Bugs had been produced. The aircraft and its technology remained a secret until

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...

. During the 1920s, what had become the U.S. Army Air Service continued to experiment with the aircraft until funding was withdrawn. From April 1917 to March 1920 the US Government spent about $275,000 ($ in ) on the Kettering Bug.

Surviving aircraft

A full-size reproduction of a Bug is on permanent display at the

National Museum of the United States Air Force The National Museum of the United States Air Force (formerly the United States Air Force Museum) is the official museum of the United States Air Force located at Wright-Patterson Air Force Base, northeast of Dayton, Ohio. The NMUSAF is the ...

. It was constructed by Museum staff members, and went on display in 1964.

Specifications (Bug)

References

External links