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thumb|right|Thorp T-18
right|thumb|T-18
The Thorp T-18 is an American, two-place, all-metal, plans-built, homebuilt aircraft designed in 1963 by John Thorp.
The aircraft was originally designed as an open cockpit aircraft, powered by a military surplus Lycoming O-290G ground power unit engine, but evolved into a fully bubble canopied aircraft powered by engines of up to .
These performance improvements made the T-18 one of the most popular homebuilt designs of the 1970s and early 1980s until the Van's Aircraft RV kitplane series came on the market. Thorp Central acquired the assets of Classic Sport Aircraft and now provides S-18 plans and parts.
By 2011 over 1600 sets of plans had been sold and 400 examples were flying.
Clive Canning flew another T-18 from Australia to England earlier the same year.
Variants
;T-18
:Original model
;T-18W
:Modified T-18, with changes designed by Lou Sunderland to provide a wider fuselage.
;T-18C
:Modified T-18, with changes designed by Lou Sunderland to provide a "convertible" wing that rotates back against the fuselage for trailering or storage.
;T-18CW
:T-18 with wider fuselage and folding wing.
;S-18
:Similar to T-18CW, with modified airfoil and other minor changes. The Sunderland changes were made in collaboration with Thorp.
thumb|Thorp S-18T
;S-18T
:Tricycle landing gear version & Classic Sport Aircraft & Thorp Central
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General characteristics
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|crew=one
|capacity=one passenger and loaded weight
|length ft= 18
|length in= 10
|length m=5.77
|span ft=20
|span in=10
|span m=6.35
|height ft=5
|height in=1
|wing area sqft= 86
|wing area sqm= 8
|empty weight lb=1000
|gross weight lb=1600
|more general=
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Powerplant
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|eng1 name=Lycoming O-360
|eng1 hp=180
|eng1 kw=135
|prop name=constant speed propeller,
||prop blade number=2
|prop dia in=72
|prop dia m= 1.83
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Performance
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|max speed mph= 200
|max speed kmh= 320
|cruise speed mph= 180
|cruise speed kmh= 292
|stall speed mph= 63
|stall speed kmh= 101
|range mi= 540
|range km=875
|range note=, with optional wing tanks
|climb rate ftmin= 1500
|climb rate ms= 7.6
|wing loading lb/sqft=18.6
|wing loading kg/m2=90
|power/mass=8.9 lb/hp (0.19 kW/kg)
|more performance=
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Armament
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|armament=<!-- if you want to use the following specific parameters, do not use this line at all-->
|avionics=
See also
References
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