Autopilot on Boeing and Airbus?
Discussion
Anyone here know how the autopilot on a modern Boeing or Airbus works?
I am working on an idea for a way of improving one of the functions of how it might function. Still at the very earliest stage, with a few dumb questions.
When autopilot is set, is it to go from A to B as a direct route and how are cross winds factored in to the path that is taken?
I am working on an idea for a way of improving one of the functions of how it might function. Still at the very earliest stage, with a few dumb questions.
When autopilot is set, is it to go from A to B as a direct route and how are cross winds factored in to the path that is taken?
Edited by Olivero on Tuesday 25th November 04:43
Olivero said:
When autopilot is set, is it to go from A to B as a direct route and how are cross winds factored in to the path that is taken?
Firstly, it depends on what mode you're using. We have 'basic' modes - laterally speaking, they are: fly track/heading, or maintain current heading/track, or the 'managed' modes, which is the route programmed into the computer.
Same with vertical modes, we have basic ones, which are basically: climb/descent at xxx feet per minute, climb/descend to xxx as quick as you can, maintain current altitude or the managed vertical profile which is programmed into the computer.
I assume you're talking about the managed modes. LNAV and VNAV (lateral and vertical navigation) as they're termed in Boeings.
The route is never the direct great circle route, i.e. Heathrow direct to Hong Kong. It's not practical, there are airspace restrictions and there are airways to be followed. Flight planning software picks routes based on many factors, such as distance, airframe/engine hours, en-route alternate requirements (weather/facilities at suitable airfields along the way, in case you have an emergency), oxygen requirements (in case you depressurise) etc. and, of course, wind.
Wind data is collected by met authorities, and from aircraft, and huge databases are built up of the winds at various altitudes along routes. The flight planning software will use this info, along with other factors, to determine the most efficient route.
The predicted en-route winds are also loaded into the flight computer, either manually entered, or uplinked via witchcraft. On a long flight, there may be 45 wind predictions, each one giving us the wind at 4 flight levels, and a descent wind profile.
On the 777, the computer also measures the actual wind being experienced, compares it to the predicted winds in the computer, and can make recommendations for the next 500 miles based on comparing the two with a mixing algorithm. Great for short flights, a bit volatile for long ones.
Cross winds aren't a factor en-route. It's minimising headwinds where possible, and maximising tailwinds. Crosswinds are an issue on take-off and departure.
Hope that helps. What's your idea?
You'd like to think so, but the aircraft themselves are fairly dumb. They can pull various bits of data such as optimum altitudes out of their databases based on weight, temperature and programmed wind (on newer boeings), but the sophisticated planning systems are the ones the planning departments use to create the flight plan. New products and programmes come out frequently, but airlines subscribe to a system for a contract period. As that system becomes more dated, Virgin may be stuck with theirs for a few more years, whereas BA may have just bought into the latest and greatest. Of course, that will reverse when BA's new system becomes more dated.
Nowadays, improvements are really just increases in analytical performance functions, however. Weather data is pretty standardised and globally accessed.
Nowadays, improvements are really just increases in analytical performance functions, however. Weather data is pretty standardised and globally accessed.
There is no industry standard, as such. Not for commercial airliners, anyhow. What you subscribe to as an airline is updated and tweaked throughout the contract, but ultimately, something better does come along from the competition. Much like trying to keep my s
tbox pc going!
The requirements by the airlines are so diverse, unique and demanding, I suppose the only option to have the product serviced and updated by the vendor is to enter in to a fairly long term contract.
I only know anything about this because I know my airline are looking to buy into another contract, as theirs is currently near the end of its useful life, in terms of keeping up with what else is out there.
tbox pc going!The requirements by the airlines are so diverse, unique and demanding, I suppose the only option to have the product serviced and updated by the vendor is to enter in to a fairly long term contract.
I only know anything about this because I know my airline are looking to buy into another contract, as theirs is currently near the end of its useful life, in terms of keeping up with what else is out there.
I use 3/4 different flight planning programmes at work fortunately being a smaller company we can afford to have multiple systems as they all have pros and cons to using them. And like anything different users prefer different systems. However as said big airlines tie into bigger contracts than we do so don't have the flexibility we do.
First, thank you to everyone who replied. It is very much appreciated.
We are a small team based in New York and France. At the moment we are working on the next generation of super computers who can quickly crunch huge amounts of data. Think of IBMs Jeopardy, but with raw data rather than quiz questions.
Our idea is to improve on the (very) short term decisions auto pilot uses. Weather effects, eg wind could be compensated for in real time. Imagine that the flight path was updated many times every second. Our aim is not to replace any of the existing systems, but rather to build an add-on that would create an optimized flight path. The biggest two benefits we imagine would be fuel savings and a smother ride.
It is too early for us to show a prototype, but not to have general discussions.
We are a small team based in New York and France. At the moment we are working on the next generation of super computers who can quickly crunch huge amounts of data. Think of IBMs Jeopardy, but with raw data rather than quiz questions.
Our idea is to improve on the (very) short term decisions auto pilot uses. Weather effects, eg wind could be compensated for in real time. Imagine that the flight path was updated many times every second. Our aim is not to replace any of the existing systems, but rather to build an add-on that would create an optimized flight path. The biggest two benefits we imagine would be fuel savings and a smother ride.
It is too early for us to show a prototype, but not to have general discussions.
Olivero said:
First, thank you to everyone who replied. It is very much appreciated.
We are a small team based in New York and France. At the moment we are working on the next generation of super computers who can quickly crunch huge amounts of data. Think of IBMs Jeopardy, but with raw data rather than quiz questions.
Our idea is to improve on the (very) short term decisions auto pilot uses. Weather effects, eg wind could be compensated for in real time. Imagine that the flight path was updated many times every second. Our aim is not to replace any of the existing systems, but rather to build an add-on that would create an optimized flight path. The biggest two benefits we imagine would be fuel savings and a smother ride.
It is too early for us to show a prototype, but not to have general discussions.
Right. Well good luck with thatWe are a small team based in New York and France. At the moment we are working on the next generation of super computers who can quickly crunch huge amounts of data. Think of IBMs Jeopardy, but with raw data rather than quiz questions.
Our idea is to improve on the (very) short term decisions auto pilot uses. Weather effects, eg wind could be compensated for in real time. Imagine that the flight path was updated many times every second. Our aim is not to replace any of the existing systems, but rather to build an add-on that would create an optimized flight path. The biggest two benefits we imagine would be fuel savings and a smother ride.
It is too early for us to show a prototype, but not to have general discussions.
Some big players in that game
http://www.geaviation.com/press/systems/systems_20...
http://www.pcworld.com/article/2152340/inside-unit...
http://www.geaviation.com/press/systems/systems_20...
http://www.pcworld.com/article/2152340/inside-unit...
Olivero said:
First, thank you to everyone who replied. It is very much appreciated.
We are a small team based in New York and France. At the moment we are working on the next generation of super computers who can quickly crunch huge amounts of data. Think of IBMs Jeopardy, but with raw data rather than quiz questions.
Our idea is to improve on the (very) short term decisions auto pilot uses. Weather effects, eg wind could be compensated for in real time. Imagine that the flight path was updated many times every second. Our aim is not to replace any of the existing systems, but rather to build an add-on that would create an optimized flight path. The biggest two benefits we imagine would be fuel savings and a smother ride.
It is too early for us to show a prototype, but not to have general discussions.
Out of curiosity why did you pick to improve on an aircraft autopilot system? Surely it's better to use that technology on something you fully aware of how it operates and where it's limitations are. We are a small team based in New York and France. At the moment we are working on the next generation of super computers who can quickly crunch huge amounts of data. Think of IBMs Jeopardy, but with raw data rather than quiz questions.
Our idea is to improve on the (very) short term decisions auto pilot uses. Weather effects, eg wind could be compensated for in real time. Imagine that the flight path was updated many times every second. Our aim is not to replace any of the existing systems, but rather to build an add-on that would create an optimized flight path. The biggest two benefits we imagine would be fuel savings and a smother ride.
It is too early for us to show a prototype, but not to have general discussions.
Olivero said:
First, thank you to everyone who replied. It is very much appreciated.
We are a small team based in New York and France. At the moment we are working on the next generation of super computers who can quickly crunch huge amounts of data. Think of IBMs Jeopardy, but with raw data rather than quiz questions.
Our idea is to improve on the (very) short term decisions auto pilot uses. Weather effects, eg wind could be compensated for in real time. Imagine that the flight path was updated many times every second. Our aim is not to replace any of the existing systems, but rather to build an add-on that would create an optimized flight path. The biggest two benefits we imagine would be fuel savings and a smother ride.
It is too early for us to show a prototype, but not to have general discussions.
I'm not really sure i understand this "macro" control idea?We are a small team based in New York and France. At the moment we are working on the next generation of super computers who can quickly crunch huge amounts of data. Think of IBMs Jeopardy, but with raw data rather than quiz questions.
Our idea is to improve on the (very) short term decisions auto pilot uses. Weather effects, eg wind could be compensated for in real time. Imagine that the flight path was updated many times every second. Our aim is not to replace any of the existing systems, but rather to build an add-on that would create an optimized flight path. The biggest two benefits we imagine would be fuel savings and a smother ride.
It is too early for us to show a prototype, but not to have general discussions.
It's clear that you want to be avoiding headwinds, and flying at the lowest drag condition (ie as high as possible) But your path around the world IS going to be set into the mandated "corridors" and at mandated altitudes. So, then what are the advantages of "macro" control, other than a plane veering all over the sky and experiencing lots of drag from constant control inputs and making passengers sick?
I think it's pretty safe to say that the existing systems are both highly optimised for ultimate economy, but also meet a massive raft of other requirements that i suspect you may not have thought about??
Olivero said:
First, thank you to everyone who replied. It is very much appreciated.
We are a small team based in New York and France. At the moment we are working on the next generation of super computers who can quickly crunch huge amounts of data. Think of IBMs Jeopardy, but with raw data rather than quiz questions.
Our idea is to improve on the (very) short term decisions auto pilot uses. Weather effects, eg wind could be compensated for in real time. Imagine that the flight path was updated many times every second. Our aim is not to replace any of the existing systems, but rather to build an add-on that would create an optimized flight path. The biggest two benefits we imagine would be fuel savings and a smother ride.
It is too early for us to show a prototype, but not to have general discussions.
Are you talking about the planning of routes before an aircraft takes off or the navigation once in the air? We are a small team based in New York and France. At the moment we are working on the next generation of super computers who can quickly crunch huge amounts of data. Think of IBMs Jeopardy, but with raw data rather than quiz questions.
Our idea is to improve on the (very) short term decisions auto pilot uses. Weather effects, eg wind could be compensated for in real time. Imagine that the flight path was updated many times every second. Our aim is not to replace any of the existing systems, but rather to build an add-on that would create an optimized flight path. The biggest two benefits we imagine would be fuel savings and a smother ride.
It is too early for us to show a prototype, but not to have general discussions.
In flight, you tend to be flying along airways or between many fixed points defined by Latitude and longitude. There's not really much scope for optimising flight path once airborne as your route needs to fit in with all the other aircraft and the required spacing between them lateraly and vertically.
You can get shortcuts between some of these fixed waypoints but again everyone needs to know exactly where you are and where you are going. As I'm sure you're aware, it's not really a viable option to take off from Heathrow and optimise your own route once airborne to get to New York. There are far to many restrictions at the moment to make this possible.
These restrictions are numerous and come in the form of different countries airspace boundaries, areas that are not always open to traffic for a variety of reasons. (military etc), other aircraft and required spacing between them, set routes through areas of high terrain (like north iran, that would enable aircraft to descend if necessary following a depressurisation and be able to fly to an airfield avoiding mountains.)
Your plan might work on smaller aircraft not flying through controlled airspace and may be more able to do their own thing with regard to choosing their own route to fly but larger aircraft are operating in a very controlled environment with little scope for constantly changing their route. Obviously you can request short term changes to your route, to avoid a thunderstorm that appears in your way and as I said ask for a shortcut but you have to negotiate all these things with air traffic control. The difficulties are then compounded if your change to route doesn't have you back on track before you enter the next controller's airspace.
If you're talking about optimising routes before the flight takes off, then there are quite a few large operators who are doing this already, they certainly take wind, temperature and all the restrictions above into consideration before creating a flight plan a couple of hours before the aircraft takes off.
Edited by el stovey on Wednesday 26th November 11:50
Ok so I'm also confused. Are we talking flight planning software or the actual "auto pilot"?
The autopilot puts inputs into the aircraft control system to achieve a desired result in Pitch, Roll and in some aircraft Yaw. Nothing more. This input is then transferred to the control column via some actuators and cables to give with respect to Boeing aircraft, tactile feedback.
Same is true for the Auto throttle.
Now, through the FMC and MCP (boeing), the pilot can command the autopilot to follow a flight path, LNAV and VNAV (magenta line) or command it to follow a heading, track or complete a climb or descent with respect to speed or vertical rate. This is calculated by the FMC and displayed on the PFD as command bars, autopilot flight director system AFDS.
The autopilot will try and center the command bars by manipulating the controls to achieve the desired flight path. When flying with the autopilot disconnected the pilot does that exact same. Fly the flight directors. (Please don't comment on manual flying skills, raw data etc as that is not what the thread is about).
With respect to differences caused by wind to heading and track, magnetic variation, True headings, these are all stored and calculated by the fmc and updated continuously as the aircraft travels through the air. It uses uploaded predicted winds to try and calculate the most optimum flight level as already stated in another post. In the event of a complete failure of the FMC the autopilot will fly the basics but it depends on the capabilities of the inertial navigation units or ADIRU's as we have on my aircraft type.
In summary, the autopilot moves the control surfaces in Pitch, Roll and Yaw. Nothing more, nothing less. Well maybe yaw.
Mud?
Awesome
The autopilot puts inputs into the aircraft control system to achieve a desired result in Pitch, Roll and in some aircraft Yaw. Nothing more. This input is then transferred to the control column via some actuators and cables to give with respect to Boeing aircraft, tactile feedback.
Same is true for the Auto throttle.
Now, through the FMC and MCP (boeing), the pilot can command the autopilot to follow a flight path, LNAV and VNAV (magenta line) or command it to follow a heading, track or complete a climb or descent with respect to speed or vertical rate. This is calculated by the FMC and displayed on the PFD as command bars, autopilot flight director system AFDS.
The autopilot will try and center the command bars by manipulating the controls to achieve the desired flight path. When flying with the autopilot disconnected the pilot does that exact same. Fly the flight directors. (Please don't comment on manual flying skills, raw data etc as that is not what the thread is about).
With respect to differences caused by wind to heading and track, magnetic variation, True headings, these are all stored and calculated by the fmc and updated continuously as the aircraft travels through the air. It uses uploaded predicted winds to try and calculate the most optimum flight level as already stated in another post. In the event of a complete failure of the FMC the autopilot will fly the basics but it depends on the capabilities of the inertial navigation units or ADIRU's as we have on my aircraft type.
In summary, the autopilot moves the control surfaces in Pitch, Roll and Yaw. Nothing more, nothing less. Well maybe yaw.
Mud?
Awesome
Olivero said:
First, thank you to everyone who replied. It is very much appreciated.
We are a small team based in New York and France. At the moment we are working on the next generation of super computers who can quickly crunch huge amounts of data. Think of IBMs Jeopardy, but with raw data rather than quiz questions.
Our idea is to improve on the (very) short term decisions auto pilot uses. Weather effects, eg wind could be compensated for in real time. Imagine that the flight path was updated many times every second. Our aim is not to replace any of the existing systems, but rather to build an add-on that would create an optimized flight path. The biggest two benefits we imagine would be fuel savings and a smother ride.
It is too early for us to show a prototype, but not to have general discussions.
My understanding of the above is that you want to make flying from point A to point B more efficient by updating the track of the aircraft several times a second to avoid any zig zagging, am I on the right lines?We are a small team based in New York and France. At the moment we are working on the next generation of super computers who can quickly crunch huge amounts of data. Think of IBMs Jeopardy, but with raw data rather than quiz questions.
Our idea is to improve on the (very) short term decisions auto pilot uses. Weather effects, eg wind could be compensated for in real time. Imagine that the flight path was updated many times every second. Our aim is not to replace any of the existing systems, but rather to build an add-on that would create an optimized flight path. The biggest two benefits we imagine would be fuel savings and a smother ride.
It is too early for us to show a prototype, but not to have general discussions.
If I am I believe that autopilot systems already do this. Certainly on radar even when we've got stonking upper winds aircraft on their own nav tend to fly what looks like a perfectly straight line I'm guessing through constant minute adjustments by the autopilot systems.
If I'm off the mark disregard!
djc206 said:
My understanding of the above is that you want to make flying from point A to point B more efficient by updating the track of the aircraft several times a second to avoid any zig zagging, am I on the right lines?
If I am I believe that autopilot systems already do this. Certainly on radar even when we've got stonking upper winds aircraft on their own nav tend to fly what looks like a perfectly straight line I'm guessing through constant minute adjustments by the autopilot systems.
If I'm off the mark disregard!
This is pretty much exactly what we are planning to do. Without wanting to go into too much detail (for obvious reasons) we have software that will optimize this action. The end result will be a plane that will need less fuel. If I am I believe that autopilot systems already do this. Certainly on radar even when we've got stonking upper winds aircraft on their own nav tend to fly what looks like a perfectly straight line I'm guessing through constant minute adjustments by the autopilot systems.
If I'm off the mark disregard!
How much deviation is there at the moment? I know the PRNAV error is in theory fairly large but the reality is that aircraft fly very precise tracks. What sort of gains are you looking at and have you based your calculations on permitted deviation or radar derived/ aircraft data from operators?
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