10 ms·

Saving Jet Fuel

50 points by marklit 12d ago

Onavo 11d ago
Anyone down to vibe code a competitor to ForeFlight?
V-eHGsd_ 12d ago
and this would work in real life too, if only we could all climb and descend entirely at pilot's discretion, direct enter enter and never have to worry about all of the other planes doing the exact same thing.
- walrus01 12d ago
  And never have to intercept certain waypoints when entering different classes of controlled airspace on the correct general heading to line up for a documented runway approach.
- scrumper 11d ago
  I think the point of this is simply to show off the author's data science and analysis skills as an advertisement for hiring them as a consultant. Certainty I hope it's not one of those intelligent outsider attempts at an obvious-but-very-wrong solution to an established problem in a complex domain (HN comment thread is the appropriate place for those.)
  - V-eHGsd_ 11d ago
    honestly you're probably right. I read the post assuming it was going to be about some exciting llm backed research into flight characteristics but it looked like it was written by an llm, or at least an llm turning notes into a blog post, "these are the packages I installed, these are the engine characteristics, these are the way points .. ", etc.
ggm 12d ago
A plot of a larger sample of post-hoc known wind and other constraints over a regular service would help enormously to sell the idea. One point at 45min faster and 25% less fuel is of course huge, but how does it map out over a year of routing?
- trillic 12d ago
  I have this for sailboat routing: https://leebow.dev/research/how-the-race-to-hawaii-is-won https://leebow.dev/research/how-the-race-to-hawaii-is-won. It solves the optimal route for every Transpac and Pac Cup start since 2011, using each race's own verified wind data (ERA5). Then it compares that route to what the fleet actually sailed. It shows the median hours the fleet gave up, how often the optimal route even falls inside the fleet's own spread (16% of the time), and how much that pattern holds from year to year. A second figure runs the same solve across 108 routes over 70 years, so you can see how much the optimal route itself varies, not just one good example. One difference from the OpenAP/scikit-decide setup: my router doesn't search a fixed grid with A*. It runs a continuous isochrone search that expands a fan of headings against the live forecast each step. That's closer to how routing is actually done for this problem, and it's what both the live product and the backtest above use.
esafak 12d ago
This is pretty cool! https://github.com/airbus/scikit-decide https://github.com/airbus/scikit-decide It's nice to see the scikit brand live on.
walrus01 12d ago
I am not sure how this approach would integrate with the common use of navigating between known/mapped IFR navigation waypoints: https://www.google.com/search?client=firefox-b-d&q=IFR+navigation+waypoints https://www.google.com/search?client=firefox-b-d&q=IFR+navig... https://skybrary.aero/articles/waypoint https://skybrary.aero/articles/waypoint https://www.flyingmag.com/how-ifr-fixes-get-their-names/ https://www.flyingmag.com/how-ifr-fixes-get-their-names/
contingencies 12d ago
It will never work because you have too many human processes in the loop. This HN share by the author is selling the idea of consulting to obtain nominal efficiency on a well established process to human organizations who are structurally opposed to it, subject to human regulators who are structurally opposed to it, in an industry that is famous for aversion to change. Nice try drumming up clients, but realistically you're not going to move the mountain a millimeter on this one. Quicker to wait for AI airports, AI ATC and AI airlines than selling to humans at this point. 20th century humanity just about spitballed together a working system, but making it efficient is not going to happen on our watch. We would do well to admit it.
- Dylan16807 12d ago
  If you said automated instead of AI that would make sense to me. But why would you want to use AI to control planes?
  - contingencies 12d ago
    It's a by-word for expert systems with management conception as well as multi-domain comprehension these days. Reasoning through failures in one sensor domain with limited data from other domains within a fixed period following strict risk protocols at 3:01AM is the sort of thing AI would excel at versus humans.
- akoboldfrying 12d ago
  Which are these "human processes in the loop"? We are talking about changing flight schedules, and I'm pretty sure that existing flight schedules are not developed by teams of people with pen and paper, but rather by powerful ILP solvers, because of (a) the immense value in optimising every aspect of them and (b) the myriad regulatory constraints that need to be met for, e.g., flight crew scheduling. Aviation is one of the few industries where the largest regular (non-capital) expense is something other than labour, namely fuel. Anything that reduces fuel costs even a little is of obvious interest to every airline. There are still the issues of coordinating flight paths to avoid collisions, and regulation (including international regulation). The former seems like a technical problem amenable to increasingly accurate approximations over time. I don't know about the latter, but I doubt it's as insurmountable as you imply. International air travel has been around longer than ILP solvers, meaning that at some point flight schedules were created by people. Now they're created by ILP solvers, and the regulatory environment successfully adapted to that change.
thenobsta 12d ago
There's a bunch of other interesting flight path optimization work going on at https://contrails.org/ https://contrails.org/. It turns out contrails contribute to 2% of global warming power and is relatively easily avoided. The cost might be a bit more fuel consumption though.
- hackernud3s 12d ago
  The fuel consumption feels like the bigger problem since contrails last for hours vs co2 that lasts damn near forever.
  - ZeroGravitas 12d ago
    They are roughly equal problems at the moment. > Recent estimates show that contrails cause about the same amount of warming each year as all the CO₂ emitted by all flights from 1940 to 2018.
    - hackernud3s 11d ago
      If we're measuring in terms of difficulty, CO2 is a much bigger problem than contrails.
      - ZeroGravitas 11d ago
        Yes, contrails appears to be mostly solvable at a small cost in time and fuel and people have started to take action on that. For most flights today though, if you only count the CO2 produced you're understanding the climate damage by about half.
        hackernud3s 11d ago
        It's one way to look at it I guess. CO2 is still the half of the damage that's way harder to fix.
        11d ago
subhro 12d ago
This is highly impractical and it is evident that the author has no idea how IFR navigation and oceanic routes work. When flying on oceanic routes and even on land, you have to intercept certain waypoints and vectored into/around airspaces. I hate to be discouraging, but maybe the author should make an attempt to understand navigation before cooking up something like this.
K0balt 12d ago
I have a close family member who flys airliners. He routinely laments having to burn up thousands of pounds of fuel on the ramp to adjust changes to the landing weight projections by dispatch and from over fueling. The amount of waste in a single error (and they are not that infrequent) is enough to heat my house for a year… and I live within 200 miles of the arctic circle. I mean, burning 1000 gallons of fancy diesel once in a while is a rounding error for jetliner operations, but still, it’s absurd that that is the best solution.
- grahamburger 11d ago
  I just had this happen on a flight yesterday. Exactly as you describe, extra fuel put the plane over weight, so we sat there letting it burn for an hour.
- lukeify 11d ago
  Aviation is notoriously resistant to change. For both good and bad reasons. Look at how long it's taken to get leaded fuel on the way out for light aircraft operations. It seems like there should be a solution to this though, either battery-electric or fuel-cell auxiliary thrust for ground operations and taxiing, or utilising tractors more to do the full aircraft ground movement, not just pushing back from the gate. Unfortunately it's impossible to suggest such changes without getting a horde of aviation nerds thinking of reasons to tell you why something isn't possible, instead of imagining how it _could_ be possible. So it's exciting to see companies like Heart Aerospace innovating in this area.
  - shrubby 11d ago
    Back in the day I was questioning operational tankering in my organization,but to no avail. Not in aviation anymore, but luckily that practice seems to be forgotten now?
    - mschuster91 11d ago
      It's making a resurgence now thanks to the various wars messing with pricing worldwide.
croemer 12d ago
If you look at the "optimal" path here looks completely unrealistic/pathological. How is it optimal to zig zag like this? The grid is clearly too coarse and that's possibly not the only issue: https://tech.marksblogg.com/theme/images/flight_planning/msrdc_MYESEeOOHL.png https://tech.marksblogg.com/theme/images/flight_planning/msr...
- cobbzilla 11d ago
  I think it’s not a great illustration; the map looks like mercator so the shortest path would be curved and closer to the green path anyway. the red line is not “as the crow flies”. It would be more fair to show deviation from the actual (great circle) shortest path. Also agree the grid seems coarse.
  - Pinus 11d ago
    Are we looking at the same map? On the one I see, showing western and central Europe, the difference between a great circle and a loxodrome (straight line on a Mercator map) for an intra-European route would be barely visible. And the map is clearly not Mercator — France looks visibly "smashed". Looks like a simple x=longitude, y=latitude projection.
  - bonzog 11d ago
    The red line is the great circle path according to the map legend.
    - cobbzilla 11d ago
      whoa yeah that is weird then
jeremiahsay 11d ago
[flagged]
buildsjets 11d ago
This is the perfect route planning software if you are the only aircraft in the sky, and fuel is your only cost. The commercial solutions exist because they consider not only the winds and fuel costs in their optimization, but also known previously cleared ATC routings, altitude restrictions whether they are charted or only documented by letter-of-agreement, expected delays due to historical congestion, pilot and cabin crew pay, crew duty time limits (your more fuel efficient route may take longer and require an entire second crew), contracted lease, finance, insurance, and maintenance rates as these are also frequently paid by the the hour, and airport arrival curfew times. And probably a few more things too. Also, you say nothing about incorporating ETOPS routing requirements into your application, and looking at the opentop source neither does it, therefore I assume this must mean this is the first time you have seen that acronym and therefore do not understand its criticality in determining aircraft routing. Might want to have your AI agent read this Wikipedia article, because your application generates many routes that are not legal to fly. https://en.wikipedia.org/wiki/ETOPS https://en.wikipedia.org/wiki/ETOPS Should I even ask if this application routes around areas that have been declared active war zones by NOTAM?
- ivraatiems 11d ago
  I don't like to be that guy, but this doesn't read as a particularly well thought-through experiment... I don't think it's as effective an advertisement for OP's consulting as they may have thought, because it suggests an inability to think within relevant context. The truth is that given the legal and ethical constraints available, routing is already relatively well-optimized in many places. (There are some places, like China's hybrid civilian-military airspace, where those constraints are extremely nasty and basically make the problem impossible to solve better than it is.) Aviation tries to solve the fuel consumption problem by designing planes to use less fuel, rather than by flying more optimal routes. There is a massive effort in aviation pretty much all the time to try to use less fuel, for every reason from cost to environmental impact to the relative accessibility of jet fuel now and into the future. It's the reason engines have gotten physically larger; it's a big part of why we don't use supersonic jets anymore as well. The efforts have been pretty sucessful: https://theicct.org/maximizing-aircraft-fuel-efficiency-designing-from-scratch/ https://theicct.org/maximizing-aircraft-fuel-efficiency-desi... There's no hubris in identifying a problem, and fairly little in thinking you might be able to help solve it, but there's a good bit in imagining nobody else has done it.
sccxy 11d ago
Good exercise but as useful as Google maps would implement "ignore traffic rules" option to save fuel.
dmitrygr 11d ago
Grepped TFA for "IFR", "NOTAM", "oceanic", "RVSM", "ETOPS", and "TFR". No results -> no point reading any further -- might as well ask my cat to opine on neurosurgery. - a pilot
- ShinyLeftPad 11d ago
  The author does use VOR/DME navaids
t0mas88 11d ago
Nice idea, but this is not how flight planning works. The optimization algorithms that airlines use consider a broader range of variables than just fuel, since you also have cost per hour that the engine is running, cost per hour for the crew, and overflight fees for different airspaces. And the output still has to be a valid flight plan route. You can't just file a flight plan for "I want this zig zag line at this altitude". Commercial flight planning software does this optimization as well, but it only selects routes that are valid. For example you have to be at a certain altitude to go one way on a route and another altitude to go the other way. ATC can't do their job if you have planes pointing at each other in opposite directions doing 1000+ km/h.
- codeduck 11d ago
  not just cost-per-hour of the crew, but also rest schedules. A more economical flight-path is all well and good, but it's useless if it means that the crew will breach their permitted duty hours.
MiroslavPokorny 11d ago
Stop pretending corporate travel is essential.
drpixie 11d ago
Hi author, where did the aircraft and engine data come from? That data looks to be rather arbitrary. Real aircraft performance is hugely dependent on aircraft weight, altitude, and ambient (air) temperature. And engine performance is very dependent on air temperature and airspeed. So your table of cruise/climb speeds etc might produce interesting results but the results are not going to be at all realistic. To give you an idea of data complexity, all airliners come with hundreds or thousands of pages of closely printed tables giving performance at specified weight, temperature, altitude, etc.
- fransje26 11d ago
  I have no doubt that Dr. J. Sun, tenured assistant professor at the TU Delft faculty of Aerospace Engineering, has absolutely no understanding whatsoever of the impact of temperature on aircraft performance. > To give you an idea of data complexity, all airliners come with hundreds or thousands of pages of closely printed tables giving performance at specified weight, temperature, altitude, etc. Make you wonder about who comes up with the theory on how to write those performance tables.. Scikit-decide, hosted by Airbus.
  - anonymars 11d ago
    Why does that guarantee this open dataset contains the requisite level of detail?
deleted 11d ago
[deleted]
gcanyon 11d ago
We shouldn't just try to save jet fuel, we should also try to avoid contrails -- only about 5% of flights generate them, but they cause roughly half of the global warming caused by flights in general. https://www.youtube.com/shorts/qBPwloCdRKw https://www.youtube.com/shorts/qBPwloCdRKw
srean 11d ago
Is it worthwhile para-droping or glide-dropping excess fuel within airport open grounds reserved for that purpose. I understand that floating into the main theatre will be a serious problem. Current weather should allow making those calls. There's also the aspect of saving money by purchasing fuel where it's cheap and having internal fuel reserves low enough at such airports so that it can be bought in significant quantities. As you can see from my comments, I am a complete newbie, just a curious one.
ryzvonusef 10d ago
A bit tangential but allow me to share an interesting anecdote. My MSc dissertation was on accounting for aeroplane fuel emission... during research I discovered an interesting fact; because of how the EU ETS (airline emissions regulations) works, (fuel consumption acts as a proxy for emissions) you can technically end up with less ETS penalty by adding a stop just before entering the EU. You see the penalty applies for the entire flight and not the portion over EU airspace... so you just have to condense the flight instead. So add a stop just before adding EU, and now you have two flights instead of one, and that second flight has lower 'emission' even though the entire trip was longer, and more importantly the extra stops's landing and take off increases fuel expenditure and thus emissions! Gives you some perspective on how legislation to reduce fuel usage and emissions can act counter to its stated goals. ____ > https://docs.lib.purdue.edu/jate/vol2/iss2/3/ > Another way to reduce the EU ETS charges is to change the route so that the last leg of the flight into or out of the EU is shorter than the current non-stop route. Changing routes to include an additional stop reduces the amount of fuel used for flight segments into and out of the EU, and therefore reduces EU ETS charges because the charges are based on fuel consumption during the entire flight, not just the portion over EU. A major US-based cargo carrier, UPS Airlines, considered adding stops to reduce the EU ETS charges (Cameron & Michaels, 2011). Instead of flying non-stop from between hubs in Hong Kong and Cologne, Germany, the route would be changed by adding a stop in Mumbai, India. While UPS estimates that the route change reduces the ETS charge by 25%, UPS also estimates that the emissions are increased by 33% due to the longer route and added takeoff and landing.
ipdashc 10d ago
The amount of downright hostile comments is insane. HN moment, I guess. Guys, I don't think he said "all the airlines need to drop what they're doing and start using my model". He's clearly just playing around with some rudimentary simulations for fun. Did we forget that we can do things on computers for fun?
- leoedin 10d ago
  Yeah, this isn't "here is a complete solution", it's "here is an interesting package for optimisation, applied in a specific way that you probably haven't heard of". I found it quite interesting. The guy isn't going to start a company around it. United aren't going to drop what they're doing. But now more people know about scikit-decide and that is a good outcome.

50 points by marklit 12d ago

Onavo 11d ago

Anyone down to vibe code a competitor to ForeFlight?

and this would work in real life too, if only we could all climb and descend entirely at pilot's discretion, direct enter enter and never have to worry about all of the other planes doing the exact same thing.

walrus01 12d ago
And never have to intercept certain waypoints when entering different classes of controlled airspace on the correct general heading to line up for a documented runway approach.
scrumper 11d ago
I think the point of this is simply to show off the author's data science and analysis skills as an advertisement for hiring them as a consultant. Certainty I hope it's not one of those intelligent outsider attempts at an obvious-but-very-wrong solution to an established problem in a complex domain (HN comment thread is the appropriate place for those.)
- V-eHGsd_ 11d ago
  honestly you're probably right. I read the post assuming it was going to be about some exciting llm backed research into flight characteristics but it looked like it was written by an llm, or at least an llm turning notes into a blog post, "these are the packages I installed, these are the engine characteristics, these are the way points .. ", etc.

ggm 12d ago

A plot of a larger sample of post-hoc known wind and other constraints over a regular service would help enormously to sell the idea. One point at 45min faster and 25% less fuel is of course huge, but how does it map out over a year of routing?

trillic 12d ago
I have this for sailboat routing: https://leebow.dev/research/how-the-race-to-hawaii-is-won https://leebow.dev/research/how-the-race-to-hawaii-is-won. It solves the optimal route for every Transpac and Pac Cup start since 2011, using each race's own verified wind data (ERA5). Then it compares that route to what the fleet actually sailed. It shows the median hours the fleet gave up, how often the optimal route even falls inside the fleet's own spread (16% of the time), and how much that pattern holds from year to year. A second figure runs the same solve across 108 routes over 70 years, so you can see how much the optimal route itself varies, not just one good example. One difference from the OpenAP/scikit-decide setup: my router doesn't search a fixed grid with A*. It runs a continuous isochrone search that expands a fan of headings against the live forecast each step. That's closer to how routing is actually done for this problem, and it's what both the live product and the backtest above use.

esafak 12d ago

This is pretty cool! https://github.com/airbus/scikit-decide https://github.com/airbus/scikit-decide It's nice to see the scikit brand live on.

walrus01 12d ago

I am not sure how this approach would integrate with the common use of navigating between known/mapped IFR navigation waypoints: https://www.google.com/search?client=firefox-b-d&q=IFR+navigation+waypoints https://www.google.com/search?client=firefox-b-d&q=IFR+navig... https://skybrary.aero/articles/waypoint https://skybrary.aero/articles/waypoint https://www.flyingmag.com/how-ifr-fixes-get-their-names/ https://www.flyingmag.com/how-ifr-fixes-get-their-names/

contingencies 12d ago

It will never work because you have too many human processes in the loop. This HN share by the author is selling the idea of consulting to obtain nominal efficiency on a well established process to human organizations who are structurally opposed to it, subject to human regulators who are structurally opposed to it, in an industry that is famous for aversion to change. Nice try drumming up clients, but realistically you're not going to move the mountain a millimeter on this one. Quicker to wait for AI airports, AI ATC and AI airlines than selling to humans at this point. 20th century humanity just about spitballed together a working system, but making it efficient is not going to happen on our watch. We would do well to admit it.

Dylan16807 12d ago
If you said automated instead of AI that would make sense to me. But why would you want to use AI to control planes?
- contingencies 12d ago
  It's a by-word for expert systems with management conception as well as multi-domain comprehension these days. Reasoning through failures in one sensor domain with limited data from other domains within a fixed period following strict risk protocols at 3:01AM is the sort of thing AI would excel at versus humans.
akoboldfrying 12d ago
Which are these "human processes in the loop"? We are talking about changing flight schedules, and I'm pretty sure that existing flight schedules are not developed by teams of people with pen and paper, but rather by powerful ILP solvers, because of (a) the immense value in optimising every aspect of them and (b) the myriad regulatory constraints that need to be met for, e.g., flight crew scheduling. Aviation is one of the few industries where the largest regular (non-capital) expense is something other than labour, namely fuel. Anything that reduces fuel costs even a little is of obvious interest to every airline. There are still the issues of coordinating flight paths to avoid collisions, and regulation (including international regulation). The former seems like a technical problem amenable to increasingly accurate approximations over time. I don't know about the latter, but I doubt it's as insurmountable as you imply. International air travel has been around longer than ILP solvers, meaning that at some point flight schedules were created by people. Now they're created by ILP solvers, and the regulatory environment successfully adapted to that change.

thenobsta 12d ago

There's a bunch of other interesting flight path optimization work going on at https://contrails.org/ https://contrails.org/. It turns out contrails contribute to 2% of global warming power and is relatively easily avoided. The cost might be a bit more fuel consumption though.

hackernud3s 12d ago
The fuel consumption feels like the bigger problem since contrails last for hours vs co2 that lasts damn near forever.
- ZeroGravitas 12d ago
  They are roughly equal problems at the moment. > Recent estimates show that contrails cause about the same amount of warming each year as all the CO₂ emitted by all flights from 1940 to 2018.
  - hackernud3s 11d ago
    If we're measuring in terms of difficulty, CO2 is a much bigger problem than contrails.
    - ZeroGravitas 11d ago
      Yes, contrails appears to be mostly solvable at a small cost in time and fuel and people have started to take action on that. For most flights today though, if you only count the CO2 produced you're understanding the climate damage by about half.
      - hackernud3s 11d ago
        It's one way to look at it I guess. CO2 is still the half of the damage that's way harder to fix.
        11d ago

subhro 12d ago

This is highly impractical and it is evident that the author has no idea how IFR navigation and oceanic routes work. When flying on oceanic routes and even on land, you have to intercept certain waypoints and vectored into/around airspaces. I hate to be discouraging, but maybe the author should make an attempt to understand navigation before cooking up something like this.

K0balt 12d ago

I have a close family member who flys airliners. He routinely laments having to burn up thousands of pounds of fuel on the ramp to adjust changes to the landing weight projections by dispatch and from over fueling. The amount of waste in a single error (and they are not that infrequent) is enough to heat my house for a year… and I live within 200 miles of the arctic circle. I mean, burning 1000 gallons of fancy diesel once in a while is a rounding error for jetliner operations, but still, it’s absurd that that is the best solution.

grahamburger 11d ago
I just had this happen on a flight yesterday. Exactly as you describe, extra fuel put the plane over weight, so we sat there letting it burn for an hour.
lukeify 11d ago
Aviation is notoriously resistant to change. For both good and bad reasons. Look at how long it's taken to get leaded fuel on the way out for light aircraft operations. It seems like there should be a solution to this though, either battery-electric or fuel-cell auxiliary thrust for ground operations and taxiing, or utilising tractors more to do the full aircraft ground movement, not just pushing back from the gate. Unfortunately it's impossible to suggest such changes without getting a horde of aviation nerds thinking of reasons to tell you why something isn't possible, instead of imagining how it _could_ be possible. So it's exciting to see companies like Heart Aerospace innovating in this area.
- shrubby 11d ago
  Back in the day I was questioning operational tankering in my organization,but to no avail. Not in aviation anymore, but luckily that practice seems to be forgotten now?
  - mschuster91 11d ago
    It's making a resurgence now thanks to the various wars messing with pricing worldwide.

croemer 12d ago

If you look at the "optimal" path here looks completely unrealistic/pathological. How is it optimal to zig zag like this? The grid is clearly too coarse and that's possibly not the only issue: https://tech.marksblogg.com/theme/images/flight_planning/msrdc_MYESEeOOHL.png https://tech.marksblogg.com/theme/images/flight_planning/msr...

cobbzilla 11d ago
I think it’s not a great illustration; the map looks like mercator so the shortest path would be curved and closer to the green path anyway. the red line is not “as the crow flies”. It would be more fair to show deviation from the actual (great circle) shortest path. Also agree the grid seems coarse.
- Pinus 11d ago
  Are we looking at the same map? On the one I see, showing western and central Europe, the difference between a great circle and a loxodrome (straight line on a Mercator map) for an intra-European route would be barely visible. And the map is clearly not Mercator — France looks visibly "smashed". Looks like a simple x=longitude, y=latitude projection.
- bonzog 11d ago
  The red line is the great circle path according to the map legend.
  - cobbzilla 11d ago
    whoa yeah that is weird then

jeremiahsay 11d ago

[flagged]

buildsjets 11d ago

This is the perfect route planning software if you are the only aircraft in the sky, and fuel is your only cost. The commercial solutions exist because they consider not only the winds and fuel costs in their optimization, but also known previously cleared ATC routings, altitude restrictions whether they are charted or only documented by letter-of-agreement, expected delays due to historical congestion, pilot and cabin crew pay, crew duty time limits (your more fuel efficient route may take longer and require an entire second crew), contracted lease, finance, insurance, and maintenance rates as these are also frequently paid by the the hour, and airport arrival curfew times. And probably a few more things too. Also, you say nothing about incorporating ETOPS routing requirements into your application, and looking at the opentop source neither does it, therefore I assume this must mean this is the first time you have seen that acronym and therefore do not understand its criticality in determining aircraft routing. Might want to have your AI agent read this Wikipedia article, because your application generates many routes that are not legal to fly. https://en.wikipedia.org/wiki/ETOPS https://en.wikipedia.org/wiki/ETOPS Should I even ask if this application routes around areas that have been declared active war zones by NOTAM?

ivraatiems 11d ago
I don't like to be that guy, but this doesn't read as a particularly well thought-through experiment... I don't think it's as effective an advertisement for OP's consulting as they may have thought, because it suggests an inability to think within relevant context. The truth is that given the legal and ethical constraints available, routing is already relatively well-optimized in many places. (There are some places, like China's hybrid civilian-military airspace, where those constraints are extremely nasty and basically make the problem impossible to solve better than it is.) Aviation tries to solve the fuel consumption problem by designing planes to use less fuel, rather than by flying more optimal routes. There is a massive effort in aviation pretty much all the time to try to use less fuel, for every reason from cost to environmental impact to the relative accessibility of jet fuel now and into the future. It's the reason engines have gotten physically larger; it's a big part of why we don't use supersonic jets anymore as well. The efforts have been pretty sucessful: https://theicct.org/maximizing-aircraft-fuel-efficiency-designing-from-scratch/ https://theicct.org/maximizing-aircraft-fuel-efficiency-desi... There's no hubris in identifying a problem, and fairly little in thinking you might be able to help solve it, but there's a good bit in imagining nobody else has done it.

sccxy 11d ago

Good exercise but as useful as Google maps would implement "ignore traffic rules" option to save fuel.

dmitrygr 11d ago

Grepped TFA for "IFR", "NOTAM", "oceanic", "RVSM", "ETOPS", and "TFR". No results -> no point reading any further -- might as well ask my cat to opine on neurosurgery. - a pilot

ShinyLeftPad 11d ago
The author does use VOR/DME navaids

t0mas88 11d ago

Nice idea, but this is not how flight planning works. The optimization algorithms that airlines use consider a broader range of variables than just fuel, since you also have cost per hour that the engine is running, cost per hour for the crew, and overflight fees for different airspaces. And the output still has to be a valid flight plan route. You can't just file a flight plan for "I want this zig zag line at this altitude". Commercial flight planning software does this optimization as well, but it only selects routes that are valid. For example you have to be at a certain altitude to go one way on a route and another altitude to go the other way. ATC can't do their job if you have planes pointing at each other in opposite directions doing 1000+ km/h.

codeduck 11d ago
not just cost-per-hour of the crew, but also rest schedules. A more economical flight-path is all well and good, but it's useless if it means that the crew will breach their permitted duty hours.

MiroslavPokorny 11d ago

Stop pretending corporate travel is essential.

drpixie 11d ago

Hi author, where did the aircraft and engine data come from? That data looks to be rather arbitrary. Real aircraft performance is hugely dependent on aircraft weight, altitude, and ambient (air) temperature. And engine performance is very dependent on air temperature and airspeed. So your table of cruise/climb speeds etc might produce interesting results but the results are not going to be at all realistic. To give you an idea of data complexity, all airliners come with hundreds or thousands of pages of closely printed tables giving performance at specified weight, temperature, altitude, etc.

fransje26 11d ago
I have no doubt that Dr. J. Sun, tenured assistant professor at the TU Delft faculty of Aerospace Engineering, has absolutely no understanding whatsoever of the impact of temperature on aircraft performance. > To give you an idea of data complexity, all airliners come with hundreds or thousands of pages of closely printed tables giving performance at specified weight, temperature, altitude, etc. Make you wonder about who comes up with the theory on how to write those performance tables.. Scikit-decide, hosted by Airbus.
- anonymars 11d ago
  Why does that guarantee this open dataset contains the requisite level of detail?

deleted 11d ago

[deleted]

gcanyon 11d ago

We shouldn't just try to save jet fuel, we should also try to avoid contrails -- only about 5% of flights generate them, but they cause roughly half of the global warming caused by flights in general. https://www.youtube.com/shorts/qBPwloCdRKw https://www.youtube.com/shorts/qBPwloCdRKw

srean 11d ago

Is it worthwhile para-droping or glide-dropping excess fuel within airport open grounds reserved for that purpose. I understand that floating into the main theatre will be a serious problem. Current weather should allow making those calls. There's also the aspect of saving money by purchasing fuel where it's cheap and having internal fuel reserves low enough at such airports so that it can be bought in significant quantities. As you can see from my comments, I am a complete newbie, just a curious one.

ryzvonusef 10d ago

A bit tangential but allow me to share an interesting anecdote. My MSc dissertation was on accounting for aeroplane fuel emission... during research I discovered an interesting fact; because of how the EU ETS (airline emissions regulations) works, (fuel consumption acts as a proxy for emissions) you can technically end up with less ETS penalty by adding a stop just before entering the EU. You see the penalty applies for the entire flight and not the portion over EU airspace... so you just have to condense the flight instead. So add a stop just before adding EU, and now you have two flights instead of one, and that second flight has lower 'emission' even though the entire trip was longer, and more importantly the extra stops's landing and take off increases fuel expenditure and thus emissions! Gives you some perspective on how legislation to reduce fuel usage and emissions can act counter to its stated goals. ____ > https://docs.lib.purdue.edu/jate/vol2/iss2/3/ > Another way to reduce the EU ETS charges is to change the route so that the last leg of the flight into or out of the EU is shorter than the current non-stop route. Changing routes to include an additional stop reduces the amount of fuel used for flight segments into and out of the EU, and therefore reduces EU ETS charges because the charges are based on fuel consumption during the entire flight, not just the portion over EU. A major US-based cargo carrier, UPS Airlines, considered adding stops to reduce the EU ETS charges (Cameron & Michaels, 2011). Instead of flying non-stop from between hubs in Hong Kong and Cologne, Germany, the route would be changed by adding a stop in Mumbai, India. While UPS estimates that the route change reduces the ETS charge by 25%, UPS also estimates that the emissions are increased by 33% due to the longer route and added takeoff and landing.

ipdashc 10d ago

The amount of downright hostile comments is insane. HN moment, I guess. Guys, I don't think he said "all the airlines need to drop what they're doing and start using my model". He's clearly just playing around with some rudimentary simulations for fun. Did we forget that we can do things on computers for fun?

leoedin 10d ago
Yeah, this isn't "here is a complete solution", it's "here is an interesting package for optimisation, applied in a specific way that you probably haven't heard of". I found it quite interesting. The guy isn't going to start a company around it. United aren't going to drop what they're doing. But now more people know about scikit-decide and that is a good outcome.