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

cruise missile A cruise missile is an unmanned self-propelled guided missile that sustains flight through aerodynamic lift for most of its flight path. Cruise missiles are designed to deliver a large payload over long distances with high precision. Modern cru ...

s. It was capable of striking ground targets up to from its launch point, while traveling at speeds of . A successful test flight was made in October, 1918. 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

In November 1917, about six months after the US declared

war War is an armed conflict between the armed forces of states, or between governmental forces and armed groups that are organized under a certain command structure and have the capacity to sustain military operations, or between such organi ...

on Germany, the United States Army aircraft board asked Charles Kettering of

Dayton, Ohio Dayton () is a city in Montgomery County, Ohio, United States, and its county seat. It is the List of cities in Ohio, sixth-most populous city in Ohio, with a population of 137,644 at the 2020 United States census, 2020 census. The Dayton metro ...

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 The Wright brothers, Orville Wright (August 19, 1871 – January 30, 1948) and Wilbur Wright (April 16, 1867 – May 30, 1912), were American aviation pioneers generally credited with inventing, building, and flying the world's first succes ...

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 Corporation, Sperry ...

designed the control and guidance system. A piloted development aircraft was built as the Dayton-Wright Bug. 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 power cycle with two strokes of the piston, one up and one down, in one revolution of the crankshaft in contrast to a four-stroke engine which re ...

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

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

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 The Wright brothers, Orville Wright (August 19, 1871 – January 30, 1948) and Wilbur Wright (April 16, 1867 – May 30, 1912), were American aviation List of aviation pioneers, pioneers generally credited with inventing, building, and flyin ...

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 (geometry), orientation and angular velocity. It is a spinning wheel or disc in ...

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

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, 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 in 1918, near the end of

World War I World War I or the First World War (28 July 1914 – 11 November 1918), also known as the Great War, was a World war, global conflict between two coalitions: the Allies of World War I, Allies (or Entente) and the Central Powers. Fighting to ...

. 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 (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...

. 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 ...

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

Specifications

References

External links