Landing

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Landing of Hawker Sea Fury FB 10

Landing is the last part of a

descent
and landing.

Aircraft

Aircraft usually land at an

helicopter landing pad, generally constructed of asphalt concrete, concrete, gravel or grass. Aircraft equipped with pontoons (floatplane) or with a boat hull-shaped fuselage (a flying boat
) are able to land on water. Aircraft also sometimes use skis to land on snow or ice.

To land, the airspeed and the rate of descent are reduced such that the object descends at a low enough rate to allow for a gentle touch down. Landing is accomplished by slowing down and descending to the runway. This speed reduction is accomplished by reducing thrust and/or inducing a greater amount of drag using flaps,

tricycle gear aircraft or on all three wheels simultaneously in the case of a conventional landing gear-equipped aircraft, commonly referred to as a "taildragger".[1][2][3][4]

Light aircraft

Piper Cherokee
landing sequence from approach to flare

In a light aircraft, power is adjusted to control the descent rate, and pitch attitude is adjusted to control airspeed,[5] although theoretically they must be adjusted together.[6]

In a light aircraft, with little

stall warning is often heard just before landing, indicating that this speed and altitude have been reached. The result is very light touch down.[4]

Light aircraft landing situations, and the pilot skills required, can be divided into four types:

  • Normal landings[4]
  • Crosswind landings - where a significant wind not aligned with the landing area is a factor[4]
  • Short field landings - where the length of the landing area is a limiting factor[4]
  • Soft and unprepared field landings - where the landing area is wet, soft or has ground obstacles such as furrows or ruts to contend with[4]

Large aircraft

Boeing 767-400ER. The smoke emanating from the left main undercarriage
wheels shows that it touched down on that main landing gear first, which is normal procedure in a left cross wind.

In large

propeller
-driven airplanes also have this feature, where the blades of the propeller are re-angled to push air forward instead of back using the 'beta range'.

Environmental factors

Factors such as

slip landing
will cause pilots to land slightly faster and sometimes with different aircraft attitude to ensure a safe landing.

Other factors affecting a particular landing might include: the plane size,

and the overall situation.

For example, landing a multi-engine

C-130 Hercules, under fire in a grass field in a war zone, requires different skills and precautions than landing a single engine plane such as a Cessna 150 on a paved runway in uncontrolled airspace, which is different from landing an airliner such as an Airbus A380 at a major airport with air traffic control
.

Required Navigation Performance (RNP) is being used more and more. Rather than using radio beacons, the airplane uses GPS-navigation for landing using this technique. This translates into a much more fluid ascent, which results in decreased noise, and decreased fuel consumption.[10]

Parachutes

A drag chute is deployed by Space Shuttle Endeavour during landing

The term "landing" is also applied to people or objects descending to the ground using a

dandelion
.

On the other hand, modern

ram-air parachutes are essentially inflatable wings that operate in a gliding flight mode. Parachutists execute a flare at landing, reducing or eliminating both downward and forward speed at touchdown, in order to avoid injury.[11]

Spacecraft

Sometimes, a safe landing is accomplished by using multiple forms of lift, thrust (propulsive landing

to successfully vertically-land and recover
its first stage, although the landed first stage was on a sub-orbital trajectory.

See also

Notes

  • ^a touchdown: tango delta, TD [13]

References

  1. ^ Aviation Glossary (2011). "Flare (ICAO Definition)". Retrieved 26 January 2011.
  2. ^ International Civil Aviation Organization (June 2010). "Phase of Flight Definitions and Usage Notes" (PDF). Retrieved 26 January 2011.
  3. ^
  4. ^ Aircraft. 64. Royal Aeronautical Society Australian Division.: 50 1984 https://books.google.com/books?id=AkspAQAAIAAJ. Retrieved 28 February 2023. {{cite journal}}: Missing or empty |title= (help)
  5. .
  6. ^ Jeffrey A., Roy (May–June 1990). "The Stabilized Approach". FAA Aviation News: A DOT/FAA Flight Standards Safety Publication. Flight Standards' Accident Prevention Program Branch, Federal Aviation Administration, Department of Transportation: 4. Retrieved 28 February 2023.
  7. ^ NASA Technical Paper. National Aeronautics and Space Administration, Scientific and Technical Information Office. 1981. p. 6. Retrieved 28 February 2023.
  8. ^ Aircraft Accident Report, United Airlines Flight 232, 19 July 1989. Appendix D: National Transportation Safety Board. p. 123.
  9. ^ "Required Navigation Performance | GE Aviation Systems". GE Aviation. Archived from the original on 29 July 2012. Retrieved 16 July 2012.
  10. ^ United States Parachute Association (2008). "Canopy piloting skills". Archived from the original on 15 October 2015. Retrieved 6 September 2011.
  11. ^ Samad Hayati, et al, Strategic Technology Development for Future Mars Missions (2013-2022) Archived 2013-02-21 at the Wayback Machine, NASA, September 15, 2009
  12. ^ "First Words of Safe Landing on Mars - Tango Delta Nominal". NASA. 21 August 2012.

External links