S81 may refer to:
Aviation
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Blériot-SPAD S.81 __NOTOC__
The Blériot-SPAD S.81 (S.81 C.1) was a French fighter aircraft developed in 1923 to a requirement by the French Air Force. It was flown competitively against the Dewoitine D.1 and was selected over that aircraft due to the Dewoitine' ...
, a French fighter aircraft
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Indian Creek USFS Airport, in Valley County, Idaho, United States
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Short S.81
__NOTOC__
The Short S.81 was an experimental British gun-carrying pusher biplane seaplane, ordered from Short Brothers by the British Admiralty in 1913 for use by the Royal Naval Air Service.
The seaplane, manufacturers serial number S.81, w ...
, an experimental British biplane seaplane
Other uses
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S81 (New York City bus) serving Staten Island
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County Route S81 (Bergen County, New Jersey)
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Daihatsu Hijet (S81), a kei truck and microvan
* , a
S-80 Plus class submarine
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Stola S81 Stratos, a concept car
* S81, a
line of the St. Gallen S-Bahn
* S81, a
postcode district for Worksop, England
* BenQ-Siemens S81, a
BenQ mobile phone
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