STOL
Overview
 
STOL is an acronym for short take-off and landing, a term used to describe aircraft
Aircraft
An aircraft is a vehicle that is able to fly by gaining support from the air, or, in general, the atmosphere of a planet. An aircraft counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil, or in a few cases the downward thrust from jet engines.Although...

 with very short runway
Runway
According to ICAO a runway is a "defined rectangular area on a land aerodrome prepared for the landing and take-off of aircraft." Runways may be a man-made surface or a natural surface .- Orientation and dimensions :Runways are named by a number between 01 and 36, which is generally one tenth...

 requirements.
There is no one accepted definition of STOL and many different definitions have been used by different authorities and nations at various times and for a myriad of regulatory and military purposes. Some accepted definitions of STOL include:

Additionally some aircraft manufacturers market their products as STOL, without providing evidence that the aircraft meets any accepted definition.
Many fixed-wing
Fixed-wing aircraft
A fixed-wing aircraft is an aircraft capable of flight using wings that generate lift due to the vehicle's forward airspeed. Fixed-wing aircraft are distinct from rotary-wing aircraft in which wings rotate about a fixed mast and ornithopters in which lift is generated by flapping wings.A powered...

 STOL aircraft are bush plane
Bush plane
A bush airplane is a general aviation aircraft serving remote, undeveloped areas of a country, usually the African bush, Alaskan and Canadian tundra or the Australian Outback...

s, though some, like the de Havilland Dash-7, are designed for use on prepared airstrips; likewise, many STOL aircraft are taildraggers
Conventional landing gear
thumb|The [[Piper PA-18|Piper Super Cub]] is a popular taildragger aircraft.thumb|right|A [[Cessna 150]] converted to taildragger configuration by installation of an after-market modification kit....

, though there are exceptions like the Quest Kodiak
Quest Kodiak
|-See also:-External links:* * *...

, de Havilland Twin Otter
De Havilland Canada DHC-6 Twin Otter
The DHC-6 Twin Otter is a Canadian 19-passenger STOL utility aircraft developed by de Havilland Canada and currently produced by Viking Air. The aircraft's fixed tricycle undercarriage, STOL abilities and high rate of climb have made it a successful cargo, regional passenger airliner and MEDEVAC...

 and the Peterson 260SE
Peterson 260SE
The Peterson 260SE is a STOL conversion of a Cessna 182 airframe made by Todd Peterson. The conversion consists of the addition of a high-lift canard and a 260 hp engine.-Design and development:...

.
Encyclopedia
STOL is an acronym for short take-off and landing, a term used to describe aircraft
Aircraft
An aircraft is a vehicle that is able to fly by gaining support from the air, or, in general, the atmosphere of a planet. An aircraft counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil, or in a few cases the downward thrust from jet engines.Although...

 with very short runway
Runway
According to ICAO a runway is a "defined rectangular area on a land aerodrome prepared for the landing and take-off of aircraft." Runways may be a man-made surface or a natural surface .- Orientation and dimensions :Runways are named by a number between 01 and 36, which is generally one tenth...

 requirements.

Definitions

There is no one accepted definition of STOL and many different definitions have been used by different authorities and nations at various times and for a myriad of regulatory and military purposes. Some accepted definitions of STOL include:

Additionally some aircraft manufacturers market their products as STOL, without providing evidence that the aircraft meets any accepted definition.

Design considerations

Many fixed-wing
Fixed-wing aircraft
A fixed-wing aircraft is an aircraft capable of flight using wings that generate lift due to the vehicle's forward airspeed. Fixed-wing aircraft are distinct from rotary-wing aircraft in which wings rotate about a fixed mast and ornithopters in which lift is generated by flapping wings.A powered...

 STOL aircraft are bush plane
Bush plane
A bush airplane is a general aviation aircraft serving remote, undeveloped areas of a country, usually the African bush, Alaskan and Canadian tundra or the Australian Outback...

s, though some, like the de Havilland Dash-7, are designed for use on prepared airstrips; likewise, many STOL aircraft are taildraggers
Conventional landing gear
thumb|The [[Piper PA-18|Piper Super Cub]] is a popular taildragger aircraft.thumb|right|A [[Cessna 150]] converted to taildragger configuration by installation of an after-market modification kit....

, though there are exceptions like the Quest Kodiak
Quest Kodiak
|-See also:-External links:* * *...

, de Havilland Twin Otter
De Havilland Canada DHC-6 Twin Otter
The DHC-6 Twin Otter is a Canadian 19-passenger STOL utility aircraft developed by de Havilland Canada and currently produced by Viking Air. The aircraft's fixed tricycle undercarriage, STOL abilities and high rate of climb have made it a successful cargo, regional passenger airliner and MEDEVAC...

 and the Peterson 260SE
Peterson 260SE
The Peterson 260SE is a STOL conversion of a Cessna 182 airframe made by Todd Peterson. The conversion consists of the addition of a high-lift canard and a 260 hp engine.-Design and development:...

. Autogyro
Autogyro
An autogyro , also known as gyroplane, gyrocopter, or rotaplane, is a type of rotorcraft which uses an unpowered rotor in autorotation to develop lift, and an engine-powered propeller, similar to that of a fixed-wing aircraft, to provide thrust...

s also have STOL capability, needing a short ground roll to get airborne, but capable of a near-zero ground roll when landing.

Runway
Runway
According to ICAO a runway is a "defined rectangular area on a land aerodrome prepared for the landing and take-off of aircraft." Runways may be a man-made surface or a natural surface .- Orientation and dimensions :Runways are named by a number between 01 and 36, which is generally one tenth...

 length requirement is a function of the square of the minimum flying speed (stall speed), and most design effort is spent on reducing this number. For takeoff
Takeoff
Takeoff is the phase of flight in which an aerospace vehicle goes from the ground to flying in the air.For horizontal takeoff aircraft this usually involves starting with a transition from moving along the ground on a runway. For balloons, helicopters and some specialized fixed-wing aircraft , no...

, large power/weight ratio
Power-to-weight ratio
Power-to-weight ratio is a calculation commonly applied to engines and mobile power sources to enable the comparison of one unit or design to another. Power-to-weight ratio is a measurement of actual performance of any engine or power sources...

s and low drag
Drag (physics)
In fluid dynamics, drag refers to forces which act on a solid object in the direction of the relative fluid flow velocity...

 help the plane to accelerate for flight. The landing run is minimized by strong brake
Brake
A brake is a mechanical device which inhibits motion. Its opposite component is a clutch. The rest of this article is dedicated to various types of vehicular brakes....

s, low landing speed, thrust reversers or spoiler
Spoiler (aeronautics)
In aeronautics, a spoiler is a device intended to reduce lift in an aircraft. Spoilers are plates on the top surface of a wing which can be extended upward into the airflow and spoil it. By doing so, the spoiler creates a carefully controlled stall over the portion of the wing behind it, greatly...

s (less common). Overall STOL performance is set by the length of runway needed to land or take off, whichever is longer.

Of equal importance to short ground run is the ability to clear obstacles, such as trees, on both take off and landing. For takeoff, large power/weight ratio
Power-to-weight ratio
Power-to-weight ratio is a calculation commonly applied to engines and mobile power sources to enable the comparison of one unit or design to another. Power-to-weight ratio is a measurement of actual performance of any engine or power sources...

s and low drag result in a high rate of climb required to clear obstacles. For landing, high drag allows the aeroplane to descend steeply to the runway without building excess speed resulting in a longer ground run. Drag is increased by use of flap
Flap (aircraft)
Flaps are normally hinged surfaces mounted on the trailing edges of the wings of a fixed-wing aircraft to reduce the speed an aircraft can be safely flown at and to increase the angle of descent for landing without increasing air speed. They shorten takeoff and landing distances as well as...

s (devices on the wings) and by a forward slip
Slip (aerodynamic)
A slip is an aerodynamic state where an aircraft is moving somewhat sideways as well as forward relative to the oncoming airflow. In other words, for a conventional aircraft, the nose will not be pointing directly into the relative wind .A slip is also a piloting maneuver where the pilot...

 (causing the aeroplane to fly somewhat sideways though the air to increase drag).

Normally, a STOL aircraft will have a large wing
Wing
A wing is an appendage with a surface that produces lift for flight or propulsion through the atmosphere, or through another gaseous or liquid fluid...

 for its weight. These wings often use aerodynamic devices like flaps, slots
Leading edge slot
A leading edge slot is an aerodynamic feature of the wing of some aircraft to reduce the stall speed and promote good low-speed handling qualities. A leading edge slot is a span-wise gap in each wing, allowing air to flow from below the wing to its upper surface...

, slats
Leading edge slats
Slats are aerodynamic surfaces on the leading edge of the wings of fixed-wing aircraft which, when deployed, allow the wing to operate at a higher angle of attack. A higher coefficient of lift is produced as a result of angle of attack and speed, so by deploying slats an aircraft can fly at slower...

, and vortex generator
Vortex generator
A vortex generator is an aerodynamic surface, consisting of a small vane or bump that creates a vortex. Vortex generators can be found on many devices, but the term is most often used in aircraft design....

s. Typically, designing an aircraft for excellent STOL performance reduces maximum speed, but does not reduce payload lifting ability. The payload is critical, because many small, isolated communities rely on STOL aircraft as their only transportation link to the outside world for passengers or cargo; examples include many communities in the Canadian north
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

 and Alaska
Alaska
Alaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...

.

Most STOL aircraft can land
Landing
thumb|A [[Mute Swan]] alighting. Note the ruffled feathers on top of the wings indicate that the swan is flying at the [[Stall |stall]]ing speed...

 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
Tundra tire
A tundra tire is a large low-pressure tire used on light aircraft to allow operations on rough terrain.-History:The tundra style tire has been independently invented at different times and places...

s), and water (using floats): these areas are often extremely short and obstructed by tall trees or hills. Wheel skis and amphibious floats combine wheels with ski
Ski
A ski is a long, flat device worn on the foot, usually attached through a boot, designed to help the wearer slide smoothly over snow. Originally intended as an aid to travel in snowy regions, they are now mainly used for recreational and sporting purposes...

s or floats, allowing the choice of landing on snow/water or a prepared runway.

STOL kits

A number of aircraft modification companies offer STOL kits that can be installed on aircraft to improve their short field performance.
  • Crosswinds STOL of Wasilla, Alaska
    Wasilla, Alaska
    Wasilla is a city in Matanuska-Susitna Borough, United States and the sixth-largest city in Alaska. It is located on the northern point of Cook Inlet in the Matanuska-Susitna Valley of the southcentral part of the state. The city's population was 7,831 at the 2010 census...

     sells STOL kits for light aircraft, including leading edge cuff
    Leading edge cuff
    Leading edge cuffs are a fixed aerodynamic device employed on fixed-wing aircraft to modify the airfoil used. They may be either factory-installed or, more commonly, an after-market modification....

    s, tip spill plates, inboard flap extensions and STOL fences. The company offers kits for Piper PA-12
    Piper PA-12
    -See also:-External links:*...

    , PA-14
    Piper PA-14 Family Cruiser
    -See also:-References:* Peperell, Roger, Piper Aircraft and their forerunners, Air-Britain Ltd, 1987, ISBN 0-85130-149-5* Simpson, Rod, General Aviation Handbook, Midland Publishing, 2005, ISBN 1-85780-222-5-External references:*...

    , PA-18, PA-20 and 22
    Piper PA-20 Pacer
    The PA-20 Pacer and PA-22 Tri-Pacer are a family of four-place, strut braced, high-wing light aircraft that were built by Piper Aircraft in the post-World War II period....

    , Bellanca Champion Model 7 series, Cessna 170B
    Cessna 170
    |-See also:-External links:* *...

    , 180
    Cessna 180
    The Cessna 180 is a four- or six-seat, fixed conventional gear general aviation airplane which was produced between 1953 and 1981. Though the design is no longer in production, many of these aircraft are still in use as personal aircraft and in utility roles such as bush...

     and 185
    Cessna 185
    -Specification for differing configurations:-References:* Jan Churchill, Hit My Smoke: Forward Air Controllers in Southeast Asia, Sunflower University Press, Manhattan KS, ISBN 0-89745-215-1...

    .
  • Horton, Inc of Wellington, Kansas
    Wellington, Kansas
    Wellington is a city in and the county seat of Sumner County, Kansas, United States. As of the 2010 census, the city population was 8,172.-19th century:...

     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
    Leading edge cuff
    Leading edge cuffs are a fixed aerodynamic device employed on fixed-wing aircraft to modify the airfoil used. They may be either factory-installed or, more commonly, an after-market modification....

    , conical cambered wingtips, control surface gap seals and wing fence
    Wing fence
    Wing fences, also known as boundary layer fences and potential fences are fixed aerodynamic devices attached to aircraft wings. Not to be confused with wingtip fences, wing fences are flat plates fixed to the upper surfaces parallel to the airflow. They are often seen on swept-wing aircraft...

    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
    Cessna
    The Cessna Aircraft Company is an airplane manufacturing corporation headquartered in Wichita, Kansas, USA. Their main products are general aviation aircraft. Although they are the most well known for their small, piston-powered aircraft, they also produce business jets. The company is a subsidiary...

     and Piper PA-28 models.
  • Micro AeroDynamics markets vortex generator
    Vortex generator
    A vortex generator is an aerodynamic surface, consisting of a small vane or bump that creates a vortex. Vortex generators can be found on many devices, but the term is most often used in aircraft design....

     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
    Elevator (aircraft)
    Elevators are flight control surfaces, usually at the rear of an aircraft, which control the aircraft's orientation by changing the pitch of the aircraft, and so also the angle of attack of the wing. In simplified terms, they make the aircraft nose-up or nose-down...

     and on the fin. Kits are available for a large number of light aircraft types.
  • 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.

STOLport

A STOLport
STOLport
A STOLport or STOLPORT is an airport designed with STOL operations in mind, normally having a short single runway; shorter than . The term does not appear to be in common usage as of 2008...

 is an airport designed with STOL operations in mind, normally having a short single runway.

STOLports are not common but can be found, for example, at London City Airport
London City Airport
London City Airport is a single-runway airport. It principally serves the financial district of London and is located on a former Docklands site, east of the City of London, opposite the London Regatta Centre, in the London Borough of Newham in east London. It was developed by the engineering...

 in Newham
Newham
-Places:* London Borough of Newham, England* Newham, Lincolnshire, England* Newham, Northumberland, England* Newham, Victoria, Australia-People:* Billy Newham , English cricketer* Edgar Newham, Australian rugby league footballer...

, The East End of London
East End of London
The East End of London, also known simply as the East End, is the area of London, England, United Kingdom, east of the medieval walled City of London and north of the River Thames. Although not defined by universally accepted formal boundaries, the River Lea can be considered another boundary...

, England.

CESTOL

CESTOL or Cruise
Cruise (flight)
Cruise is the level portion of aircraft travel where flight is most fuel efficient. It occurs between ascent and descent phases and is usually the majority of a journey. Technically, cruising consists of heading changes only at a constant airspeed and altitude...

 Efficient Short Takeoff and Landing, is sometimes used to describe aircraft with both very short runway requirements and high cruise speeds (greater than mach
Mach number
Mach number is the speed of an object moving through air, or any other fluid substance, divided by the speed of sound as it is in that substance for its particular physical conditions, including those of temperature and pressure...

0.8).

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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