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{{Short description|Class of airplanes that are designed to takeoff and land in a short distance}}
{{Other uses|Stol (disambiguation)}}
[[File:20120902 Zenair STOL CH 701 Krakow 8579.jpg|thumb|upright=1.2|A [[Zenith STOL CH701|Zenair CH 701]] STOL light aircraft]]

A '''short takeoff and landing''' ('''STOL''') [[aircraft]] is a [[fixed-wing aircraft]] that can takeoff/land on short [[runway]]s. Many STOL-designed aircraft can operate on [[airstrip]]s with harsh conditions (such as [[high altitude]] or ice).  STOL aircraft, including those used in scheduled passenger airline operations, can be operated from [[STOLport]] airfields that feature short runways.

==Design ==
{{Refimprove section|date=July 2022}}
[[File:87 GAF Nomad 22SL Philippine Air Force (7838564596).jpg|thumb|[[GAF Nomad]] of the Philippine Air Force]]
STOL aircraft come in configurations such as [[bush plane]]s, [[autogyro]]s, and [[Conventional landing gear|taildraggers]], and those such as the [[de Havilland Canada Dash-7]] that are designed for use on conventional airstrips. The [[PAC P-750 XSTOL]], the [[Daher Kodiak]], the [[de Havilland Canada DHC-6 Twin Otter]] and the [[Wren 460]] have STOL capability, needing a short ground roll to get airborne, but are capable of a near-zero ground roll when landing.{{Citation needed|date=December 2009}}

[[File:YA2F-1 tilting pipes NAN6-60.jpg|thumb|[[Grumman A-6 Intruder|Grumman YA2F-1 Intruder]] with tilting STOL nozzles<ref>https://ntrs.nasa.gov/api/citations/19810016529/downloads/19810016529.pdf{{Dead link | date=May 2025 | fix-attempted=yes}}</ref>]]

For any plane, the required [[runway]] length is a function of the square of the [[stall speed]] (minimum flying speed), and much design effort is spent on minimizing this number. For [[takeoff]], large [[power-to-weight ratio|power/weight ratio]]s and low [[drag (physics)|drag]] help the plane to accelerate for flight. For landing, the length is minimized by strong [[brake]]s, low landing speed, and [[thrust reverser]]s or [[Spoiler (aeronautics)|spoiler]]s. Overall STOL performance is set by the longer of the runway needed to land or take off.<ref>{{Cite web|date=2015-12-02|title=What's the definition of STOL in aviation?|url=https://www.vikingair.com/twin-otter-series-400/twin-otter-answers/what%E2%80%99s-definition-stol-aviation|access-date=2021-12-20|website=Viking Air Ltd|language=en}}</ref>

[[File:Fieseler Storch (7582553016).jpg|thumb|[[Fieseler Storch]] with German [[Luftwaffe]] markings]]

Of equal importance to runway length is the ability to clear obstacles, such as hills, beyond the runway. For takeoff, large [[power-to-weight ratio|power/weight ratio]]s and low drag increase the rate of climb – required to clear obstacles. For landing, high drag allows the plane to descend steeply without building speed, which would require a longer ground run. Drag is increased by use of [[flap (aircraft)|flap]]s on the wings and by [[Slip (aerodynamic)|forward slip]] (causing the plane to fly somewhat sideways to increase drag).<ref> Denker, John S. "11 Slips, Skids, and Snap Rolls". See How It Flies. Av8n.com. Archived from the original on Nov 11, 2023.</ref>

Typically, a STOL aircraft has a large [[wing]] for its weight. These wings may use [[aerodynamic]] devices like flaps, [[leading edge slot|slots]], [[Leading edge slats|slats]], and [[vortex generator]]s.<ref name="gtri.gatech.edu">{{cite web|url=http://www.gtri.gatech.edu/casestudy/powered-lift|title=Powered Lift: Novel GTRI Design Would Let Commercial Jets Use Smaller Airports While Reducing Noise|publisher=[[Georgia Tech Research Institute]]|access-date=2010-10-28}}</ref> Typically, achieving excellent STOL performance reduces maximum speed, but not [[Payload (air and space craft)|payload]] ability. The payload is critical, because many small, isolated communities rely on STOL aircraft as their only link to the outside world for passengers or cargo; examples include many communities in the [[Canada|Canadian north]] and [[Alaska]].<ref> Time-Life editors 1983, p. 34</ref><ref> "Bush Flying". US Centennial of Flight Commission. Archived from the original on 24 July 2008. Retrieved 14 July 2008.</ref><ref>"Alaska". World Atlas. Retrieved 14 July 2008.</ref>

Most STOL aircraft can [[landing|land]] either on- or off-airport. Typical off-airport landing areas include snow or ice (using skis), fields or gravel riverbanks (often using special fat, low-pressure [[tundra tire]]s), and water (using [[Float (nautical)|float]]s): these areas are often short and obstructed by trees or hills. Wheel skis and amphibious floats combine wheels with [[ski]]s or floats, allowing landing on snow/water.{{Citation needed|date=December 2009}}

==Kits==
[[File:VortexGenerators01.JPG|thumb|right|Micro Dynamics vortex generators mounted on the wing of a [[Cessna 182|Cessna 182K]]]]
A number of aircraft modification companies offer STOL kits for improving short-field performance.

*[[Crosswinds STOL]] of [[Wasilla, Alaska]], sells STOL kits for light aircraft, including [[leading edge cuff]]s, tip spill plates, inboard flap extensions and STOL fences. The company offers kits for [[Piper PA-12]], [[Piper PA-14 Family Cruiser|PA-14]], [[Piper PA-18|PA-18]], [[Piper PA-20 Pacer|PA-20 and 22]], [[American Champion Citabria|Bellanca Champion Model 7 series]], [[Cessna 170|Cessna 170B]], [[Cessna 180|180]] and [[Cessna 185|185]].<ref name="Crosswinds">{{cite web|url = http://www.crosswindsstol.com |title = Crosswinds STOL Inc.|access-date = 2011-02-23|last =Crosswinds S.T.O.L. Inc.|year = 2011}}</ref>
*[[Horton, Inc]], of [[Wellington, Kansas]], offers STOL kits under the brand name ''Horton STOL-Craft'', emphasizing that the modifications increase safety by allowing forced landings to occur at lower speeds and thus improve survivability. The Horton modifications include a drooped [[leading edge cuff]], conical cambered [[wingtip]]s, control surface gap seals and [[wing fence]]s. The company says: "On an average you can expect to get a 4-7 knot reduction in stall speeds. Flying at these lower stall speeds you can reduce the take-off and landing distances by 10%". Horton STOL kits are available for several [[Cessna]] and [[Piper PA-28]] models.<ref name="HortonDescription">{{cite web|url = http://www.hortonstackdoor.com/stolcraft_description.htm|title = Description of the Horton STOL Kit|access-date = 2009-12-26|last = Horton, Inc.|archive-date = 2008-11-21|archive-url = https://web.archive.org/web/20081121152728/http://www.hortonstackdoor.com/stolcraft_description.htm|url-status = dead}}</ref><ref name="HortonFAQ">{{cite web|url = http://www.hortonstackdoor.com/stolcraft_faq.htm|title = Frequently Asked Questions About the Horton STOL Kit|access-date = 2009-12-26|last = Horton, Inc.|archive-date = 2008-10-06|archive-url = https://web.archive.org/web/20081006174413/http://www.hortonstackdoor.com/stolcraft_faq.htm|url-status = dead}}</ref><ref name="HortonPrice">{{cite web|url = http://www.hortonstackdoor.com/stolcraft_pricing.htm|title = Horton STOL Kit Pricing|access-date = 2009-12-26|last = Horton, Inc.|archive-date = 2018-01-09|archive-url = https://web.archive.org/web/20180109004134/http://www.hortonstackdoor.com/stolcraft_pricing.htm|url-status = dead}}</ref>
*[[Micro AeroDynamics]] markets [[vortex generator]] modification kits for "STOL benefits". The Micro kits are small vortex generators that are glued to the wing leading edge, as well as the underside of the [[Elevator (aircraft)|elevator]] and on the fin. Kits are available for a large number of light aircraft types.<ref name="Micro">{{cite web|url = http://www.microaero.com/|title = Micro Vortex Generators for Single and Twin Engine Aircraft|access-date = 2009-12-26|last =Micro AeroDynamics Inc|year = 2009}}</ref>
*[[Sierra Industries]] sells Robertson STOL kits, marketed under the name R/STOL, incorporate a drooped leading edge cuff, wing fences, drooping ailerons and an automatic trim system. The company says that installation "allows 15 to 25 MPH slower approaches and requires up to 40% less runway distance". R/STOL kits are available for various Cessna models.<ref name="R/STOLAbout"> {{cite web|url = http://www.sijet.com/sitemap_rstol.aspx|title =Sierra R/STOL High Lift Systems for Piston Engine Aircraft|access-date = 2009-12-26|last = Sierra Industries|year = 2007}}</ref><ref name="R/STOL"> {{cite web|url = http://www.sijet.com/SierraRSTOL_performanceComparison.aspx|title = Sierra R/STOL Performance Comparison Charts|access-date = 2009-12-26|last = Sierra Industries|year = 2007}}</ref><ref name="R/STOLMods"> {{cite web|url = http://www.sijet.com/d563beaf-cce6-4770-9feb-e4bf0c42bc76.aspx|title = Modifications - Sierra R/STOL High Lift Systems for Piston Engine Aircraft|access-date = 2009-12-26|last = Sierra Industries|year = 2007}}</ref>
*[[Stolairus Aviation]] of Kelowna, British Columbia, has developed STOL Kits for the [[de Havilland Canada DHC-2 Beaver]] and [[de Havilland Canada DHC-3 Otter]] to increase lift and reduce stall speeds. The DHC-2 Beaver STOL Kit includes a contoured leading edge, flap-gap seals, wing fences and drooped wingtips. The DHC-3 Otter STOL Kit includes a contoured leading edge and drooped wingtips.<ref>[http://www.stolairus.com "DHC-2 Beaver."] Stolairus Retrieved: February 2, 2012.</ref>

==STOLport==
{{excerpt|STOLport}}

==CESTOL==
[[Cruise (aeronautics)|Cruise]]-efficient short takeoff and landing (CESTOL) have very short runway requirements and cruise speeds greater than [[Mach number|Mach]] 0.8.<ref name="gtri.gatech.edu"/><ref>{{cite web|first=Craig E|last=Hange|url=https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20090036801_2009036530.pdf|title=Short Field Take-Off and Landing Performance as an Enabling Technology for a Greener, More Efficient Airspace System|publisher=[[Ames Research Center]], [[NASA]]|date=2005-04-25|access-date=2010-10-28}}</ref><ref>{{cite news|url=http://www.onlineamd.com/amd-0511-novel-design-reducing-noise.aspx|title=Novel Design|publisher=Aerospace Manufacturing and Design|date=May 2011|access-date=2011-05-08}}</ref>

==Definitions==
Many definitions of STOL have been used over time and for regulatory and military purposes.<ref name="Columbia" /> These include:

{{Quote
 | quote =([[US Department of Defense|DOD]]/[[NATO]]) The ability of an aircraft to clear a 50-foot (15 meters) obstacle within 1,500 feet (450 meters) of commencing takeoff or in landing, to stop within 1,500 feet (450 meters) after passing over a 50-foot (15 meters) obstacle. 
 | source =Department of Defense Dictionary of Military and Associated Terms (JP 1-02)<ref>{{cite web | url= http://www.dtic.mil/doctrine/dod_dictionary/data/s/7020.html | work= [[United States Department of Defense]] | title= Department of Defense Dictionary of Military and Associated Terms (JP 1-02) | access-date= 2009-12-22 | archive-url= https://web.archive.org/web/20110605071237/http://www.dtic.mil/doctrine/dod_dictionary/data/s/7020.html | archive-date= 2011-06-05 | url-status= dead }}</ref> 
}}

{{quote
|quote=the ability of aircraft to take off and clear a 50-foot obstruction in a distance of 1,500 feet from beginning the takeoff run. It must also be able to stop within 1,500 feet after crossing a 50-foot obstacle on landing.
|source=''Dictionary of Aeronautical Terms''<ref name="Crane">Crane, Dale: ''Dictionary of Aeronautical Terms, third edition'', page 492. Aviation Supplies & Academics, 1997. {{ISBN|1-56027-287-2}}</ref>
}}
 
{{quote
|quote=An aircraft that, at some weight within its approved operating weight, is capable of operating from a STOL runway in compliance with the applicable STOL characteristics and airworthiness, operations, noise, and pollution standards" and ""aircraft" means any machine capable of deriving support in the atmosphere|source=[[Transport Canada]]<ref name="TransportCanada">{{cite web|url = http://www.tc.gc.ca/eng/civilaviation/secretariat-terminology-glossary-204.htm#short_takeoff_and_landing_aircraft|title = Glossary for Pilots and Air Traffic Services Personnel (TP 1158E)|access-date = 2009-12-15|last = Transport Canada|author-link = Transport Canada|date=November 2009}}</ref><ref name="AeronauticsAct">{{cite web|url = http://www.tc.gc.ca/civilaviation/regserv/affairs/aeronauticsact/nov2007.htm|title = Aeronautics Act - November 2007 Consolidation|access-date = 2009-12-25|last = Transport Canada|author-link = Transport Canada|date=September 2009}}</ref> and [[Arizona Department of Transportation]]<ref name="ADT">{{cite web|url=http://www.azdot.gov/aviation/library/MP_PDF/1G4_MP_APP_B.pdf |title=Appendix B |access-date=2009-12-15 |last=Arizona Department of Transportation |author-link=Arizona Department of Transportation |url-status=dead |archive-url=https://web.archive.org/web/20090314082256/http://www.azdot.gov/aviation/library/MP_PDF/1G4_MP_APP_B.pdf |archive-date=March 14, 2009 }}</ref> }}

{{quote
|quote=an aircraft with a certified performance capability to execute approaches along a glideslope of 6 degrees or steeper and to execute missed approaches at a climb gradient sufficient to clear a 15:1 missed approach surface at sea level... A STOL runway is one which is specifically designated and marked for STOL aircraft operations, and designed and maintained to specified standards.
|source= US [[Federal Aviation Administration]]<ref name="USDOT">{{cite web|url = http://testimony.ost.dot.gov/test/pasttest/84test/kern1.PDF|title = Statement of John Kern, Deputy Director of Flight Operations, FAA|access-date = 2009-12-15|last = US House of Representatives Committee of Science and Technology|date = July 1984|archive-date = 2016-12-22|archive-url = https://web.archive.org/web/20161222225637/http://testimony.ost.dot.gov/test/pasttest/84test/kern1.PDF|url-status = dead}}</ref> 
}}

{{quote
|quote=Heavier-than-air craft that cannot take off and land vertically, but can operate within areas substantially more confined than those normally required by aircraft of the same size. Derived from short takeoff and landing aircraft.
|source= McGraw-Hill Dictionary of Scientific & Technical Terms<ref name="McGrawHill">{{cite web|url = http://encyclopedia2.thefreedictionary.com/STOL+aircraft|title = STOL aircraft |access-date = 2009-12-25|last = McGraw-Hill Dictionary of Scientific & Technical Terms|year = 2003}}</ref> 
}}

{{quote
|quote=heavier-than-air craft, capable of rising from and descending to the ground with only a short length of runway, but incapable of doing so vertically. The precise definition of an STOL aircraft has not been universally agreed upon. However, it has been tentatively defined as an aircraft that upon taking off needs only 1,000 ft (305 m) of runway to clear a 50-ft (15-m) obstacle at the end of that distance and upon landing can clear the same obstacle and then land within 1,000 ft.
|source= Columbia Encyclopedia<ref name="Columbia">{{cite web|url = http://www.answers.com/topic/stol|title = short takeoff and landing aircraft |access-date = 2009-12-25|last = Columbia Encyclopedia |website = [[Answers.com]] }}</ref>

}}

{{quote
|quote=The STOL mode of flight is one during which an airplane taking off or landing is operated at climb-out and approach speeds lower than the conventionally accepted margins of airspeed above the power-off stalling speed of the airplane.
|source= Lieutenant Colonel Walter P. Maiersperger, USAF (Ret)<ref name="Maiersperger">{{cite web |url = http://www.airpower.au.af.mil/airchronicles/aureview/1968/mar-apr/maiersperger.html |title = What is STOL? |access-date = 2009-12-25 |last = Maiersperger |first = Walter P., Lieutenant Colonel, USAF (Ret) |date = March–April 1968 |archive-date = 2011-07-22 |archive-url = https://web.archive.org/web/20110722140149/http://www.airpower.au.af.mil/airchronicles/aureview/1968/mar-apr/maiersperger.html |url-status = dead }}</ref> 
}}

Some manufacturers market their products as STOL without specifying that the aircraft meets an accepted functional definition.<ref name="FisherHorizon1">{{cite web|url = http://www.fisherflying.com/index.php?option=com_content&view=article&id=40&Itemid=22|title = Horizon 1 |access-date = 2009-10-27|last = Fisher Flying Products}}</ref>

==Rough-field capability==
Rough-field capability is the ability to land/take-off from an unprepared/damaged runway or grass field, highway, wasteland or other ad hoc site. Rough-field capable aircraft usually have high wings, reinforced landing gear, and STOL capability.<ref>{{Cite report |url=https://www.sae.org/publications/technical-papers/content/650844/ |title=Soft and Rough Field Landing Gears |last1=Williams |first1=W. W. |last2=Williams |first2=G. K. |last3=Garrard |first3=W. C. J. |date=1965-10-04 |publisher=SAE Technical Paper |issue=650844 |location=Warrendale, PA |language=English}}</ref><ref>{{Cite web |last=Kaminski-Morrow |first=David |title=VIDEO: An-148 performs rough-field demonstration |url=https://www.flightglobal.com/video-an-148-performs-rough-field-demonstration/111924.article |access-date=2025-01-29 |website=Flight Global |language=en}}</ref><ref>{{Cite web |title=Japan Evaluates C-2's Rough-Field Performance {{!}} Aviation Week Network |url=https://aviationweek.com/defense/aircraft-propulsion/japan-evaluates-c-2s-rough-field-performance |access-date=2025-01-29 |website=aviationweek.com}}</ref><ref>{{cite web|url=https://www.faa.gov/sites/faa.gov/files/regulations_policies/handbooks_manuals/aviation/airplane_handbook/07_afh_ch6.pdf |title=FAA Airplane Handbook}}</ref><ref>{{cite web|url=https://media.defense.gov/2019/May/13/2002130791/-1/-1/0/FP_0026_OWEN_LAUNCHING_THE_WORKHORSE_VERTICAL_OR_SUPER-SHORT_TAKEOFF_CAPABILITIES_FOR_THE_NEXT_THEATER_AIRLIFT_AIRCRAFT.PDF |title=Owen Launching The Workhorse Vertical Or Short Takeoff Capabilities For The Next Theater Airlift Aircraft}}</ref><ref>{{cite web|url=https://www.rand.org/content/dam/rand/pubs/notes/2007/N1985-1.pdf |publisher=Rand |title=N1985|year=1985}}</ref><ref>{{cite web|url=https://www.sto.nato.int/publications/AGARD/AGARD-AG-45/AGARD-AG-45.pdf|publisher=NATO|title=Asgard AG 45}}</ref><ref>{{Cite report |url=https://www.sae.org/publications/technical-papers/content/911199/ |title=Landing Gear Design Requirements for Bomb-Damaged Runway Operations |last1=Pollack |first1=Henry M. |last2=Urch |first2=Ralph E. |date=1991-04-01 |publisher=SAE Technical Paper |issue=911199 |location=Warrendale, PA |language=English}}</ref>{{Excessive citations inline|date=January 2025}} 

===List of rough-field capable aircraft===
*[[AHRLAC Holdings Ahrlac]]
*[[Airbus A400M]]
*[[Arado Ar 232 Tausendfüßler]]
*[[British Aerospace 125]]
*[[Cessna A-37 Dragonfly]]
*[[Cessna Caravan]]<ref>{{Cite web |title=Cessna Caravan Turboprop {{!}} Textron Aviation |url=https://cessna.txtav.com/en/turboprop/caravan |access-date=2025-01-29 |website=cessna.txtav.com |language=en}}</ref>
*[[General Atomics Mojave]]
*[[General Dynamics F-111 Aardvark]]
*[[PAC P-750 XSTOL]]
*[[Pilatus PC-24]]<ref>{{Cite web |title=PC-24 Rough Field Certification Campaign Brought to a Successful Conclusion {{!}} Pilatus Aircraft Ltd |url=https://www.pilatus-aircraft.com/en/news-events/media-release/pc-24-certified-for-take-offs-and-landings-on-unpaved-runways-plus-steep-approaches |access-date=2025-01-29 |website=www.pilatus-aircraft.com |language=en}}</ref>
*[[SEPECAT Jaguar]]
*[[Sukhoi Su-7]]
*[[Tupolev Tu-142]]

==See also==
*[[List of STOL aircraft]]
*[[ESTOLAS]]
*[[VTOL]]

==References==
{{Reflist|30em}}

==External links==
{{external media
| float  = right
| video1 = [http://www.flyingmag.com/videos/video-channel/just-aircraft-superstol-short-takeoff-and-landing?con=outbrain&obref=obnetwork&src=related&con=outbrain&obref=obnetwork STOL Ultralight taking off and landing]
}}
* {{Wiktionary-inline|STOL}}
* [http://www.zenithair.com/stolch801/design/design.html Anatomy of a STOL Aircraft: Designing a Modern Short Take-Off and Landing Aircraft by Chris Heintz]
* {{Cite web |first=Loz|last=Blain|date=2025-03-22 |title=$9 billion in pre-orders for super-slow, super-quiet aircraft |url=https://newatlas.com/aircraft/electra-estol-9-billion-preorders/ |access-date=2025-04-02 |website=New Atlas |language=en-US}}
{{Types of take-off and landing}}

[[Category:STOL aircraft| ]]
[[Category:Types of take-off and landing]]