Deadstick landing

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A deadstick landing, also called a dead-stick landing, is a type of forced landing when an aircraft loses all of its propulsive power and is forced to land. The "stick" does not refer to the flight controls, which in most aircraft are either fully or partially functional without engine power, but to the traditional wooden propeller, which without power would just be a "dead stick".[1] When a pilot makes an emergency landing of an aircraft that has some or all of its propulsive power still available, the procedure is known as a precautionary landing.

All fixed-wing aircraft have some capability to glide with no engine power; that is, they do not sink straight down like a stone, but rather continue to glide moving horizontally while descending. For example, with a glide ratio of 15:1, a Boeing 747-200 can glide for 150 kilometres (93 mi) from a cruising altitude of 10,000 metres (33,000 ft). After a loss of power, the pilot’s goal is to maintain a safe airspeed and fly the descending aircraft to the most suitable landing spot within gliding distance, then land with the least amount of damage possible. The area open for potential landing sites depends on the original altitude, local terrain, the engine-out gliding capabilities of the aircraft, original airspeed and winds at various altitudes. Part of learning to fly a fixed-wing aircraft is demonstrating the ability to fly safely without an engine until prepared to make (or actually making) a landing. Gliders, unless they have an auxiliary motor, do all their flying without power, and a trained pilot can touch down on virtually any spot he or she picks from the air.

The success of the deadstick landing largely depends on the availability of suitable landing areas. A competent pilot gliding a relatively light, slow plane to a flat field or runway should result in an otherwise normal landing, since the maneuver is not especially difficult, requiring only strict attention and good judgement concerning speed and energy. A heavier, faster aircraft or a plane gliding into mountains and/or trees could result in substantial damage.

With helicopters, a forced landing involves autorotation, since the helicopter glides by allowing its rotor to spin freely during the descent thus generating lift.

Single engine failure[edit]

When a single engine aircraft suffers an engine failure, it must do a dead-stick landing. Pilatus Aircraft established the procedures following an engine failure in a PC-12 after flight tests : the turn-back procedure necessitates a 1,200 ft (370 m) altitude in visual meteorological conditions and 2,500 ft (760 m) in instrument meteorological conditions. At a 15° bank angle, the maneuver takes 161 s., results in a 2,350 ft (720 m) loss of altitude and a 5,050 ft (1,540 m) turn radius while at 45° it takes 46 s. with a turn radius of 1,450 ft (440 m) and loses 1,005 ft (306 m). The flaps take 30 s. to extend to 40° and the landing gear 12 s. Its "glide envelope" assumes an overall glidepath angle of 4.5° (a 12.7 glide ratio) in a clean configuration, the propeller feathered and a best glide speed of 114 kn (211 km/h) indicated airspeed.[2]

A danger in losing power comes from the pilot subsequently allowing a critical loss of airspeed, which will result in excessively fast loss of altitude and, when poorly handled, loss of control. The instinct to "stretch the glide" by pulling the nose up beyond its optimum point will simply make the aircraft sink faster. The other major concern is attempting a low altitude turn back to the airport, should engine power be lost shortly after takeoff. This "impossible turn" has killed many pilots because it very likely will result in a crash whereas a landing straight ahead (or within a few degrees of the initial flight path) would be survivable.[3]

Deadstick landings of passenger aircraft[edit]

There have been several well-known instances of large jet airliners successfully executing a deadstick landing.

See also[edit]

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