It's hard to appreciate an aircraft's rates of change in altitude, in particular with respect to its travel through the mass of air, rather than over the ground, since the latter is affected significantly by wind-speed (the distance an aircraft travels with respect to the ground is highly variable, compared to the distance it travels with respect to the air around it).

Then, when climb profiles are plotted, it's always on a graph with a hugely compressed horizontal axis (naturally, because it's hard to discern much information when one axis is a thousand times longer than the other).

Finally, when climb/descent rates are given they are usually in vertical distance/minutes, which is useful from an aviation point of view, but hard to compare with a vertical distance/horizontal distance measurement, or for example the familiar gradient figure that would be used to describe the slope of a road.

So, assuming absolutely still air throughout a flight, what might the altitude profile as plotted against distance look like, for a typical airliner on a flight long enough to be at cruising altitude for a few hours?

And, what sort of gradients would be represented for its climb after take-off and its descent towards its destination?

  • 2
    $\begingroup$ I can probably add some info later, but in the meantime - why don’t you convert one of the climb profiles you have into a diagram with a common axis scale for the visualisation you would like to see? $\endgroup$ – Cpt Reynolds Jul 22 '18 at 14:29
  • $\begingroup$ If I have to assume "absolutely still air throughout a flight" the plot given by any online flight tracker answers your question. The problem in what you ask is that unless you are equipped in recording the wind conditions throughout a flight, you will never be able to reconstruct what you seek. $\endgroup$ – Federico Jul 24 '18 at 8:00
  • $\begingroup$ @Federico Since aircraft are equipped with both altimeters and airspeed indicators, this information must exist. I'm pretty sure pilots have an idea of the figures, for example. And clearly the information I'm after will not be available by looking at online trackers, which are a complete red herring here. I'm not interested in reconstructing information from some particular set of data, I'm asking about what a typical example might look like. $\endgroup$ – Daniele Procida Jul 24 '18 at 9:03
  • $\begingroup$ Daniele, may I suggest you pass by in chat? I am not sure I follow you, and if the discussion drags on it is better to have it in chat. $\endgroup$ – Federico Jul 24 '18 at 9:07
  • $\begingroup$ I have written here what I do not understand Please join $\endgroup$ – Federico Jul 24 '18 at 10:04

It is somewhat unclear what you want to achieve.

If you want to know how it looks like, you can search for some papers like this. To keep it short, altitude vs distance curve is pretty much similar to altitude vs time, but climb and descent segments are more curved with larger second derivatives for climb and descend. For details please read the paper.

If you are interested in some analysis, you need two components: flight data itself and data analysis software.

If you are looking for professional flight data analysis systems, for example, flightDataServices, generally they are not provided for free, but even if you have an access, you still need flight data for analysis. It can be more difficult to find it. If that is what you are looking for, just google "Flight Analysis Software" and "Flight Data".

You can do that analysis by yourself though, with a little less accuracy than a professional system. The closest option for getting an accurate flight data is FlightAware.com. They do not provide altitude vs distance out-of-the-box, but they provide plenty of data for further analysis. For example, this flight. You can open track log and see altitude/speed vs time (which is not you are looking for, but useful for a 'big picture'), and in the log itself you can find latitude, longitude, speed and rate of climb for some points. The points are provided with a less-than-a-minute frequency, which is pretty precise. It is not so hard to export them in any spreadsheet or CSV and generate whatever you are interested in: a pretty common data visualization task. It can be easily done with Matlab/Excel/LibreOffice. For example, altitude vs distance travelled, course vs time, rate of climb vs time, rate of climb vs distance etc.

If you are looking for data visualization software specified for flight analysis, I am not sure that something exists that fits all requests. Especially an online tool. The reasons are: flightaware provides both data and the most common plots (i. e. alt vs time and speed vs time); and if you already have data, it's pretty easy to plot whatever you want using Matlab/R/Python/Excel.

  • $\begingroup$ Well, it doesn't include data for altitude/distance, which is what I'm concerned with, so no, unfortunately it doesn't provide the most basic thing I am asking about. It provides data instead for altitude/time (which as the question points out is readily available but not what I am looking for). $\endgroup$ – Daniele Procida Jul 22 '18 at 21:21
  • $\begingroup$ It provides latitude and longitude, and speed. You can copy that data to any tool (even Excel) and plot altitude/distance. $\endgroup$ – avtomaton Jul 22 '18 at 21:55
  • $\begingroup$ That would a) be quite a lot of work in itself, for something that I hoping to find exists already b) would be very hard to do accurately taking into account the fact that aircraft typically make multiple turns particularly in climb and descent phases, and c) fails to take into account that it's distance through air, not distance over ground, that the question is concerned with. $\endgroup$ – Daniele Procida Jul 23 '18 at 7:04
  • $\begingroup$ Yes, it is a little bit of work in itself, copy, paste to any spreadsheet and make 4-5 mouse clicks after that to create a diagram. And about all other points... You have a horizontal and vertical profiles with latitude and longitude in a track log. What distance through air are you talking about? Lat-log are ground references! All turns of airliners are usually very shallow, and positions in a track log are given at least once a minute. Pretty accurate for computation. $\endgroup$ – avtomaton Jul 23 '18 at 9:33
  • $\begingroup$ Please read the question again. I know you are trying to be helpful, but I spent quite a bit of time formulating the question to specify what, exactly, I was trying to find out. Possibly I didn't express it as clearly as I'd hoped, and thank you for trying to answer, but the information you keep trying to tell me about is not the information I am seeking. I don't think you have understood the question. $\endgroup$ – Daniele Procida Jul 23 '18 at 15:11

Your Answer

