1. why does the autopilot landing lands very hard
It is what the name suggests—the autopilot flies the airplane without the human pilots controlling “hands on.”
“Basically it is a computer that is running very, very fast,” said Paul Robinson, president and CEO of AeroTech Research. “It can almost fly the plane completely between takeoff and landing.”
The autopilot system relies on a series of sensors around the aircraft that pick up information like speed, altitude and turbulence. That data are ingested into the computer, which then makes the necessary changes. Basically, it can do almost everything a pilot can do. Key phrase: almost everything.
Before takeoff, the pilot will enter the route into the computer, giving it a start and end position and exactly how to get there. Throughout that route there are a series of points that the computer will note, each having its own speed and altitude.
The autopilot does not steer the airplane on the ground or taxi the plane at the gate. Generally, the pilot will handle takeoff and then initiate the autopilot to take over for most of the flight. In some newer aircraft models, autopilot systems will even land the plane.
Explanation:
Autoland systems were designed to make landing possible in visibility too poor to permit any form of visual landing, although they can be used at any level of visibility. They are usually used when visibility is less than 600 meters runway visual range and/or in adverse weather conditions, although limitations do apply for most aircraft—for example, for a Boeing 747-400 the limitations are a maximum headwind of 25 kts, a maximum tailwind of 10 kts, a maximum crosswind component of 25 kts, and a maximum crosswind with one engine inoperative of five knots. They may also include automatic braking to a full stop once the aircraft is on the ground, in conjunction with the autobrake system, and sometimes auto deployment of spoilers and thrust reversers.
Autoland may be used for any suitably approved instrument landing system (ILS) or microwave landing system (MLS) approach, and is sometimes used to maintain currency of the aircraft and crew, as well as for its main purpose of assisting an aircraft landing in low visibility and/or bad weather.
Autoland requires the use of a radar altimeter to determine the aircraft's height above the ground very precisely so as to initiate the landing flare at the correct height (usually about 50 feet (15 m)). The localizer signal of the ILS may be used for lateral control even after touchdown until the pilot disengages the autopilot. For safety reasons, once autoland is engaged and the ILS signals have been acquired by the autoland system, it will proceed to landing without further intervention, and can be disengaged only by completely disconnecting the autopilot (this prevents accidental disengagement of the autoland system at a critical moment) or by initiating an automatic go-around. At least two and often three independent autopilot systems work in concert to carry out autoland, thus providing redundant protection against failures. Most autoland systems can operate with a single autopilot in an emergency, but they are only certified when multiple autopilots are available.
The autoland system's response rate to external stimuli work very well in conditions of reduced visibility and relatively calm or steady winds, but the purposefully limited response rate means they are not generally smooth in their responses to varying wind shear or gusting wind conditions – i.e., not able to compensate in all dimensions rapidly enough – to safely permit their use.
The first aircraft to be certified to CAT III standards, on 28 December 1968,[1] was the Sud Aviation Caravelle, followed by the Hawker-Siddeley HS.121 Trident in May 1972 (CAT IIIA) and to CAT IIIB during 1975. The Trident had been certified to CAT II on 7 February 1968.
Autoland capability has seen the most rapid adoption in areas and on aircraft that must frequently operate in very poor visibility. Airports troubled by fog on a regular basis are prime candidates for Category III approaches, and including autoland capability on jet airliners helps reduce the likelihood that they will be forced to divert by bad weather.
1 votes Thanks 1
williamaccuors254
Autoland is highly accurate. In his 1959 paper,[2] John Charnley, then Superintendent of the UK Royal Aircraft Establishment's (RAE) Blind Landing Experimental Unit (BLEU), concluded a discussion of statistical results by saying that "It is fair to claim, therefore, that not only will the automatic system land the aircraft when the weather prevents the human pilot, it also performs the operation much more precisely".
williamaccuors254
Previously, autoland systems have been so expensive that they were rarely used on small aircraft. However, as display technology has developed the addition of a head up display (HUD) allows for a trained pilot to manually fly the aircraft using guidance cues from the flight guidance system.
There are still a lot of questions about exactly what happened to the Germanwings jetliner that crashed Tuesday. The announcement Thursday by a French prosecutor that the co-pilot appears to have acted deliberately while the pilot was locked out of the cabin, has raised questions about a key aviation feature: the autopilot.
CNBC spoke to industry experts to better understand these computer systems that have become a part of how we fly today.
Answers & Comments
Answer:
1. why does the autopilot landing lands very hard
It is what the name suggests—the autopilot flies the airplane without the human pilots controlling “hands on.”
“Basically it is a computer that is running very, very fast,” said Paul Robinson, president and CEO of AeroTech Research. “It can almost fly the plane completely between takeoff and landing.”
The autopilot system relies on a series of sensors around the aircraft that pick up information like speed, altitude and turbulence. That data are ingested into the computer, which then makes the necessary changes. Basically, it can do almost everything a pilot can do. Key phrase: almost everything.
Before takeoff, the pilot will enter the route into the computer, giving it a start and end position and exactly how to get there. Throughout that route there are a series of points that the computer will note, each having its own speed and altitude.
The autopilot does not steer the airplane on the ground or taxi the plane at the gate. Generally, the pilot will handle takeoff and then initiate the autopilot to take over for most of the flight. In some newer aircraft models, autopilot systems will even land the plane.
Explanation:
Autoland systems were designed to make landing possible in visibility too poor to permit any form of visual landing, although they can be used at any level of visibility. They are usually used when visibility is less than 600 meters runway visual range and/or in adverse weather conditions, although limitations do apply for most aircraft—for example, for a Boeing 747-400 the limitations are a maximum headwind of 25 kts, a maximum tailwind of 10 kts, a maximum crosswind component of 25 kts, and a maximum crosswind with one engine inoperative of five knots. They may also include automatic braking to a full stop once the aircraft is on the ground, in conjunction with the autobrake system, and sometimes auto deployment of spoilers and thrust reversers.
Autoland may be used for any suitably approved instrument landing system (ILS) or microwave landing system (MLS) approach, and is sometimes used to maintain currency of the aircraft and crew, as well as for its main purpose of assisting an aircraft landing in low visibility and/or bad weather.
Autoland requires the use of a radar altimeter to determine the aircraft's height above the ground very precisely so as to initiate the landing flare at the correct height (usually about 50 feet (15 m)). The localizer signal of the ILS may be used for lateral control even after touchdown until the pilot disengages the autopilot. For safety reasons, once autoland is engaged and the ILS signals have been acquired by the autoland system, it will proceed to landing without further intervention, and can be disengaged only by completely disconnecting the autopilot (this prevents accidental disengagement of the autoland system at a critical moment) or by initiating an automatic go-around. At least two and often three independent autopilot systems work in concert to carry out autoland, thus providing redundant protection against failures. Most autoland systems can operate with a single autopilot in an emergency, but they are only certified when multiple autopilots are available.
The autoland system's response rate to external stimuli work very well in conditions of reduced visibility and relatively calm or steady winds, but the purposefully limited response rate means they are not generally smooth in their responses to varying wind shear or gusting wind conditions – i.e., not able to compensate in all dimensions rapidly enough – to safely permit their use.
The first aircraft to be certified to CAT III standards, on 28 December 1968,[1] was the Sud Aviation Caravelle, followed by the Hawker-Siddeley HS.121 Trident in May 1972 (CAT IIIA) and to CAT IIIB during 1975. The Trident had been certified to CAT II on 7 February 1968.
Autoland capability has seen the most rapid adoption in areas and on aircraft that must frequently operate in very poor visibility. Airports troubled by fog on a regular basis are prime candidates for Category III approaches, and including autoland capability on jet airliners helps reduce the likelihood that they will be forced to divert by bad weather.
Answer:
There are still a lot of questions about exactly what happened to the Germanwings jetliner that crashed Tuesday. The announcement Thursday by a French prosecutor that the co-pilot appears to have acted deliberately while the pilot was locked out of the cabin, has raised questions about a key aviation feature: the autopilot.
CNBC spoke to industry experts to better understand these computer systems that have become a part of how we fly today.