Kettering Bug
{{Short description|Experimental unmanned aerial torpedo}}
{{use American English|date=January 2023}}
{{Infobox aircraft
|name=Bug
|image=Kettering Bug.jpg
|size=300px
|alt=a small unmanned biplane aircraft resting on a pair of rails
|caption=
|type = Missile
|national_origin = United States
|manufacturer = Dayton-Wright Company
|designer = Charles Kettering
|first_flight = 2 October 1918
|introduction =
|retired =
|primary_user=
|produced =
|number_built=
}}
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 {{convert|75|mi|km}} from its launch point, while traveling at speeds of {{convert|50|mph}}. 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.{{Cite news|url=https://io9.gizmodo.com/the-first-drones-used-in-world-war-i-453365075|title=The First Drones, Used in World War I|last=Miller|first=Ron|work=io9|access-date=2018-05-07|language=en-US}} 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 on Germany, the United States Army aircraft board asked Charles Kettering of Dayton, Ohio to design an unmanned "flying machine" which could hit a target at a range of {{convert|40|mi}}. Kettering's design, formally called the Kettering Aerial Torpedo but later known as the Kettering Bug, was built by the Dayton-Wright Airplane Company. Orville Wright acted as an aeronautical consultant on the project, while Elmer Ambrose 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 V4 {{convert|40|hp|kW|adj=on|lk=in}} DePalma engine.{{cite web|url=https://airandspace.si.edu/collection-objects/depalma-v-4-engine|title=Smithsonian - DePalma, V-4 Engine|website=airandspace.si.edu|access-date=2019-07-12|archive-date=2019-07-12|archive-url=https://web.archive.org/web/20190712073108/https://airandspace.si.edu/collection-objects/depalma-v-4-engine|url-status=dead}} The engine was mass-produced by the Ford Motor Company for about $40 each.{{citation
|last = Glines
| first = C.V.
| title = Ford's Forgotten Aviation Legacy
| newspaper = Aviation History
| issue = May 2008
| url = http://www.historynet.com
}} 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 {{convert|50|mph}}. 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. {{ISBN|0-16-067599-5}}.
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 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, 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 {{convert|180|lb}} 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. The first flight on October 2, 1918{{Cite web|url=http://www.hq.nasa.gov/office/pao/History/Timeline/1915-19.html|title=NASA timeline|website=www.hq.nasa.gov|accessdate=February 26, 2023|archive-date=April 12, 2021|archive-url=https://web.archive.org/web/20210412145702/https://www.hq.nasa.gov/office/pao/History/Timeline/1915-19.html|url-status=dead}} was a failure: the plane climbed too steeply after takeoff, stalled and crashed.{{Cite web |url=http://www.ctie.monash.edu/hargrave/rpav_usa.html |title=Remote Piloted Aerial Vehicles : The 'Aerial Target' and 'Aerial Torpedo' in the USA |access-date=2006-08-10 |archive-date=2011-07-16 |archive-url=https://web.archive.org/web/20110716210742/http://www.ctie.monash.edu/hargrave/rpav_usa.html |url-status=dead }} 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."{{Cite web |url=http://stinet.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA162646 |title=The Evolution of the Cruise Missile |last= Werrell |first= Kenneth P. |pages= 23–28 |access-date=2007-01-11 |archive-url=https://web.archive.org/web/20070304213844/http://stinet.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA162646 |archive-date=2007-03-04 |url-status=dead }}
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.
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 $275,000 (${{formatnum:{{Inflation|US-GDP|275000|1920|r=-4}}}} in {{CURRENTYEAR}}) on the Kettering Bug.The Evolution of the Cruise Missile by Kenneth P. Werrell, page 28
Surviving aircraft
Image:KetteringAerialTorpedo.jpg in Dayton, Ohio]]
A full-size reproduction of a Bug is on permanent display at the National Museum of the United States Air Force in Dayton, Ohio. It was constructed by Museum staff members, and went on display in 1964.{{cite web |title=Kettering Aerial Torpedo "Bug" |url=https://www.nationalmuseum.af.mil/Visit/Museum-Exhibits/Fact-Sheets/Display/Article/198095/kettering-aerial-torpedo-bug/ |website=National Museum of the United States Air Force |access-date=7 September 2021 |date=7 April 2015}}
Specifications
{{Aircraft specs
|prime units?=imp
|ref= National Museum of the United States Air Force[https://www.nationalmuseum.af.mil/Visit/Museum-Exhibits/Fact-Sheets/Display/Article/198095/kettering-aerial-torpedo-bug/ Kettering Aerial Torpedo “Bug”]
|capacity =
|length m=3.8
|length ft=12
|length in=6
|span m=4.5
|span ft=15
|height m=2.3
|height ft=7.7
|gross weight kg=240
|gross weight lb= 530
|eng1 name=De Palma V4
|eng1 type=piston engine
|eng1 number=1
|eng1 kw= 30
|eng1 hp= 40
|cruise speed kmh=80
|max speed mph = 120
|cruise speed mph=50
|range km=121
|range miles=75
|armament={{convert|180 |lb|kg|abbr=on}} high explosive
}}
See also
References
{{reflist}}
External links
{{Commonscatinline}}
- [http://www.daviddarling.info/encyclopedia/K/Kettering_Bug.html Encyclopedia of Astrobiology, Astronomy, and Space Flight: Kettering Bug]
- [http://www.ctie.monash.edu/hargrave/rpav_usa.html Monash University information] {{Webarchive|url=https://web.archive.org/web/20110716210742/http://www.ctie.monash.edu/hargrave/rpav_usa.html |date=2011-07-16 }}
Category:Unmanned aerial vehicles of the United States
Category:Cruise missiles of the United States
Category:Dayton-Wright aircraft
Category:1910s United States experimental aircraft
Category:Single-engined tractor aircraft