Improved airports

[jamespetts]

I have been working on some improvements to airports this week-end whislt I am waiting for Bernd to finish working on tracking down network desyncs related to the braking physics code. The results are on my -devel branch (and see the Pak128.Britain-Ex Github repository for the compatible pakset).

The new features are:
(1) aircraft all have a minimum runway length in meters, and cannot take off/land from a runway shorter than that length; and
(2) all airports must have control towers.

The second feature is disabled by default, as many paksets do not define control towers (is_control_tower=1 in the .dat file for an extension building). This feature is enabled by setting allow_airports_without_control_towers = 0 in simuconf.tab. Airports without control towers show a purple status colour and have [NO CONTROL TOWER] appended to their names in the schedule and information windows.

As to the first feature, the minimum runway length for each type of aircraft is set by specifying minimum_runway_length=[a number in meters] in the individual aircrafts' .dat files. The figure is displayed in the depot/replacer window (only when it is dealing with aircraft, however). The runway length is measured using the meters per tile setting.

These changes involve changing the pakset and saved game formats, so this is incompatible with previous -devel builds (as ever, this does not affect release builds).

I hope to see some rather more realistic looking airports in the next server game! Incidentally, as to the difficulties encountered previously with airports not having enough capacity, this has not been fixed with changes to the code, but the following pakset changes should between them alleviate the issue:
(1) larger aircraft (thanks to Giuseppe);
(2) a lower passenger factor; and
(3) a lower proportion of passengers travelling long distances;
and the following user tips should likewise assist:
(1) do not use aircraft for short journeys (approx. 150km); and
(2) for large airports, have multiple terminals (each a separate stop, linked with land transport), with its own runway.

I should be very interested in any thoughts on these matters, and anyone who is able to compile from -devel to test.

[ӔO]

Nice work!
Multiple terminals and avoiding short hops sounds like a good idea.


Were one way signals were added to the pakset? I've realized that you can totally jam an airport if there is only one runway and too many airplanes trying to take off or land.

[jamespetts]

Thank you!

Do you mean one way signs for runways or taxiways? Taxiways I don't think enforce collision detection/occupancy, and runways are inherently one way for taking off/landing. How would you imagine one way signs working in airports?

[ӔO]

One way signs for both, although just on the taxiway is fine.
You can designate landing only and takeoff only if the taxiway to the runway is one way only. This would improve traffic flow, as the airplanes tend to just use the nearest runway possible.

For reasons that I don't really understand, sometimes an airplane can queue itself on the runway for a parking spot at a terminal. This causes the runway to become occupied and any airplane that wants to take off, can't. This would never happen if there is one runway for landing and one for take off.

There's already quite a good one way sign in pak128 that fits in just fine with pak brit.

[jamespetts]

Ahh, I see what you mean, a landing only runway and a takeoff only runway - isn't that what they do at Heathrow? You don't happen to have a link to the sources of the Pak128 one way sign, do you...?

[ӔO]

hmmm, I think you might have to ask fabio for the link to the sources.

All I know is that it's part of a "airports.misc.pak" and needs to be extracted.
The easily identifiable double arrows should be "roadsign.airport_oneway.pak".

[isidoro]

Giving a game function to control towers is very nice.  But make them compulsory is a bit too much imho.

Other possibilities:

   
• Make them compulsory only after certain date (they need radio, don't they)
• Make them compulsory only for big airports (big may mean with several runways, with at least one of the runways longer that a certain length (which, btw, would allow to indirectly connect this to point 1 if you force heavy planes from a date on to use longer runways))...
• Make them optional but, if there, waiting time for landing/taking off is shorter
• ...

Regarding the length of the runways topic, how would you mark that an airplane cannot take off/land due to the runway being too short?  Or would this be calculated when routing only?

[jamespetts]

AEO -

thank you for that. Is there a screenshot of it somewhere that might tell me whether it really fits in properly with Pak128.Britain colours?

Isidoro -

why is it too much to have control towers compulsory? After all, they are in real life! Note also that the feature can be disabled.

As to the second question - I have only been able to make it work calculating at the routing stage, so aircraft get an orange tooltip, "runway too short" when they try to take off/land. I'd like to be able to have a more sophisticated method of doing this, ideally enabling the runway length to be shown in the airport's information window, but I'm not sure how it might be done at present.

[ӔO]

here is what it looks like in pak brit.

[jamespetts]

Thank you - that is helpful!

[dom700]

Whats the typical runway length you are having in mind? Im just wondering how this change would look like for pak128 with the A380 having HUGE runways.

[greenling]

Jamrespetts
You want build in zones for Landing and Starting?

[jamespetts]

Whats the typical runway length you are having in mind? Im just wondering how this change would look like for pak128 with the A380 having HUGE runways.

I try to find the real runway length for the actual aircraft in question, and then use Simutrans-Experimental's meters per tile setting to translate that into tiles.

[ӔO]

The runway length required at full load for the larger aircraft is typically 3500m.

An-225 needs 3500m at full load.
747 series needs slightly less than that. Typically around 3200m to 3300m
A380 needs even less than that. Its lifting capabilities just outperform 747 by a wide margin.

For sizes of the larger airplanes, you can see here: http://upload.wikimedia.org/wikipedia/commons/5/52/Giant_planes_comparison.svg
A380 is very stubby with an advanced wing design that allows it to have some impressive lifting capabilities, which also keeps runway length to a minimum. Boeing 747 and An-225, on the other hand, are built with 70's technology, which are not as good, and require the extra length.

Your typical short runway is under 2200m, while the longer ones can range from 3400m to 4000m.
Most of the major airports were rebuilt with 747 in mind, since that came about in the 1970's. Quite a lot of them only have runways that are 3200~3500m long. Quite a lot of airports do get modernized over the years and one thing they do is add runway length to add a margin of safety.

Runway lengths over 4000m should, typically, not be necessary for commercial aircraft, but they do exist. For instance, high altitude airports. Since the air is thinner higher up, the runway length needs increase to compensate for the lack of performance. I don't think it's necessary to program altitude and air thickness, but I only mention it for the sake of completeness.

[jamespetts]

AEO,

interesting information. May I ask - where do you find the information on these minimum runway lengths? I ask because the lengths seem to be greater than my research has so far indicated.

[ӔO]

@james

There is usually a specification publication on various airplanes floating around.
except for airbus, who don't seem like they want to publish their data too much.

Boeing is pretty good about that: http://www.boeing.com/commercial/airports/plan_manuals.html
Just select an airplane and then select "airplane performance"

What I do know about A380 is that they had to design it so that it would work with most airports without too many modifications, which means it had to perform just as well or better than a 747.

[prissi]

Looking at those specs (like for the 707) you find all length between 2300 and 4500 (extrapolated) for wet and dry wether, different engine types and airport elevations.

Maybe a range is gamewise rather better to implement and easier to research.

[jamespetts]

Interesting information - thank you!

[Milko]

Hello James

I can help? 
I have a lot of information on aircraft that I designed (typically data will ricavavo technical manuals).
I read that you mean to use the track length in meters and turn it into tiles, you are not likely to have slopes that are too long?
For example, with m / = 200 tiles, a 3.5km long runway was made ​​of 17 tiles, are a little too much?
You have a makeobj windows for testing?

Giuseppe

[Carl]

Since the new default value for meters per tile in pak.britain will (IIRC) be 125, even a 2.5km runway would be 20 tiles. That sounds like a lot, but it sounds perfectly acceptable to me. Requiring proper airport infrastructure will help to balance air travel in relation to other modes of transport (and why shouldn't airports be realistically sized?)


I had only one small comment on your initial post, James. I think that flights of <150km are relatively common in the USA as part of hub-and-spoke systems. For instance, Boston airport has flights to nearby Barnstable, Vineyard Haven and Provincetown -- all of which are about 100km away.

[el_slapper]

<150km air transport is really special.

I like the idea of correct runway sizes. 20 squares will force me to think harder. At the same time, I already imagine the newbie hordes swarming the forum & complaining that air transport is broken. The runway size should be clearly visible from many screens, on the main screen(maybe a tooltip), the depot, etc..... interface has to be extremely friendly, on that one.

[jamespetts]

Interesting discussion. I ought to note that 150km was a very approximate figure, and there may well be exceptions to general rules in any event, but the basic point that aircraft ought be used only for long distances still holds, I think.

It would indeed be most interesting to see realistically sized and designed airports - much more fun than a two tile long runway with no control tower, I think!

[wlindley]

The 150km figure ought to be derived from some ratio of maximum, average, or speedbonus speeds... so it will change with technology as the game progresses.

Should the same sort of minimum distance calculation hold also for maglev trains?  Or indeed for horse-drawn omnibus when compared to the speed of walking... isn't there already something like that? perhaps simply generalize it.

[ӔO]

I would suggest checking some of the high traffic areas.


The only one I know of, which has quite a fierce competition on rail, air and road, is Tokyo to Osaka. That's around 500~520km.
It is approximately 3hrs by train, 1hr by airplane and 7hrs by bus.

-3hrs by train. Quite obvious and this is already programmed inside experimental. Next to no waiting time. Fair is slightly cheaper than airplane.
-1hr by airplane. Around 1hr of waiting time, and another 1hr of traveling to get to and from the airports to major rail hubs. That's 3hrs total. What's more, there is a limit to how many flights can be flown in a day.
-7hrs by bus. This is the slightly mysterious one for experimental. What it is, is a cheap, usually overnight, ride. It's very cheap compared to the other two, but the time consumed traveling is done while sleeping. It is quite popular, despite its long travel time.

For britain, I'm guessing London to Edinburgh or London to Paris? I'm not entirely sure where all the airports are for UK, nor do I fully understand where the high speed trains run.

[Carl]

The only "official" highspeed line in the UK is the one to Paris -- though the west coast/east coast main lines (and others?) run at 125mph.

While it's true that there's a limit to the amount of flights that can be run in a day, the limit is pretty high. You can run an hourly air service -- I believe this more or less exists on routes like Heathrow to New York -- and there's no reason in principle why you couldn't double that, if demand were there.

[jamespetts]

We can't do cost comparisons in Experimental because that would be a bit too complicated (to code, for the computer to do quickly enough for good performance in large games, and for players to do without the game ceasing to be fun), but a the journey time based computations of rail versus air are well set out. London to Edinburgh, London to Glasgow and London to Manchester (as well as London to Paris) are good examples of similar journey time comparisons, although in the Anglo-Scottish routes, the rail journey is considerably longer than three hours, and for the London to Manchester route, the flight is shorter than an hour, I think.

[kierongreen]

Unless you are connecting to other flights, London - Paris is now dominated by Eurostar (TGV train). By air it's a bit under 3 hours (45 minutes flying, 2 hours checkin and getting to airport), Eurostar is a bit over 2 hours. Coach isn't really competitive, maybe 7 hours or so as the coaches have to go via Eurotunnel (checkin time 30+ minutes) or via the ferry (checkin time again, and longer crossing of the Channel).

London - Edinburgh or Glasgow is more balanced. The journey as the crow flies is further than to Paris, the railways are slower speed, but they are more direct. Flying is about 3 hours with travel and checkin, train is 4 1/2, coach is 8 hours. Coach is extremely cheap, plane is often cheaper than the train, but not always. As with the example given in Japan, coach travel can be done overnight on this distance. All are used extensively to cater for different types of passengers, and all run regularly (at least hourly for trains and planes during the day). Coaches are more bunched up in terms of timetables, lots leave London or Edinburgh/Glasgow late at night and arrive early in the morning, and again, lots leave early in the morning and arrive early evening.

Elsewhere, across England the vast majority of public transport is split between coach (very cheap) and train (usually expensive, but some cheap tickets). Comfort is usually far better on trains than coaches though, unless you happen to get stuck on an overcrowded train of course (these actually aren't that common and are usually predictable). Air travel doesn't compete on the high traffic routes within England (e.g. London - Birmingham or Manchester) as the distances are too small (only lightly used routes from North East to South West are worth flying).

Intercity lines in the UK run mostly at 100mph or more - a lot of the Great Western, East Coast and West Coast have been upgraded to 125mph. There is a prospect that conventional lines could be relatively easily upgraded to 140mph also (this has been tested before). Due to relatively high speeds on conventional railways High Speed Rail within the UK is unlikely to drastically reduce journey times, on the longest journeys to Scotland for example it will probably only reduce them by 1 hour. However congestion is a major problem on British Railways - during the 1960's severe cutbacks left a network now unable to cope with todays levels of traffic.

The transatlantic routes don't have an hourly service - the flights tend to all run at more or less similar times, so there will be maybe 20 flights leaving late morning from various airports in the UK over the period of about 2 hours, getting into various airports in the US in the mid-afternoon. Hence you don't really get a choice as to what time of day you fly at, just where you are flying to and from (and with which airline).

[jamespetts]

Hello James

I can help? 
I have a lot of information on aircraft that I designed (typically data will ricavavo technical manuals).
I read that you mean to use the track length in meters and turn it into tiles, you are not likely to have slopes that are too long?
For example, with m / = 200 tiles, a 3.5km long runway was made ​​of 17 tiles, are a little too much?
You have a makeobj windows for testing?

Giuseppe

Oops - almost forgot to reply to this. I don't think that the runway lengths would be too long: as Carl says, long runways are realistic. In fact, the next version of Pak128.Britain-Ex will have 125m/tile, so the runways will be even longer: a 3.5km runway will be 28 tiles long. This will, as Carl points out, force people to put down realistic airport infrastructure, and make airports more resource intensive (and less suitable to be placed very near cities) than they have been in Simutrans in the past. This is a good thing, I think.

Yes, your help in adding minimum runway lengths would be very welcome! You don't actually need a -devel makeobj to code the values into the .dat files, as the standard release makeobj will simply ignore the strings. Adding the minimum runway length settings from your information for all aircraft (and replacing my values if I have got them wrong) would be very useful indeed (especially if you could do it on your Github branch so that I can simply merge your changes).

If you want to test it, however, you will need not only the latest -devel makeobj, but a binary build from the latest -devel branch, as the existing release candidate is too old to be able to read files written. I can upload these for you if you'd find that helpful?

[kierongreen]

Another interesting side effect of forcing runways to be 30 tiles or so long is that planes take over half a minute of real time to taxi down this length of runway. Even time taken to take off and land (demanding full use of runway) will be 10 seconds or so at least. That's ontop of the taxiing time of course. Capacity at airports will be very much dependent on having parallel taxiways to keep the main runway clear. Maybe two runways will minimise need for taxiing but I'm not sure. Of course, all this extra time will add to total journey time as well. For comparison, a two track railway in simutrans can support high speed trains running every five seconds (in standard simutrans anyway, I'm not sure whether braking distances change this for experimental?), and those trains will also be carrying more passengers each than any airliner.

So, capacity will be vastly reduced from at present, while maintenance costs and land required will be much greater. Looking at it just now it would seem that late on in the game air travel will also be restricted to extremely long distance routes as effectively they will start off with over 100 tile extra to travel over trains, and added to this is the time taken to travel this distance. So for distances of less than around 600 tiles (75km) planes will take longer than high speed trains to cover this distance. With transfer times and getting to airports you can probably double this. So for map sizes of less than 1000x1000 planes will not be practical, and you'll need to be playing map sizes of well over 2000x2000 (once you take into account positions of cities) for there to be a significant advantage of having any air routes at all. I'm not sure how friendly this is to people wanting to play smaller maps...

In a way this is all realistic of course (and I agree that having to build huge airports is good), but rebalancing will be essential to ensure that there is a place for air travel within simutrans-experimental.

[ӔO]

28 tile runway will be quite something to see in action.

Although, there should still be a possibility for smaller airports for commuter turboprops and regional jets. These kinds of airports would only require, approximately, 16 tile or 2000m runways.

[sdog]

With 125m per tile, any maps below 2000 tiles length would be a very tiny sandbox anyway. It is also a good idea to have very oblong maps, to allow long distances, without having too much area.

>20 tiles runways still seem quite a bit extreme. That's about 1/6 of the size of a typical map size when simutrans started.

I wonder if simutrans' approach is still effective with such large map sizes, and such a narrowly spaced grid.

-7hrs by bus. This is the slightly mysterious one for experimental. What it is, is a cheap, usually overnight, ride. It's very cheap compared to the other two, but the time consumed traveling is done while sleeping. It is quite popular, despite its long travel time.

This likely only works due to the incredible ability of japanese to sleep anywhere and for any time, when they have a chance to do so.

[dom700]

Another interesting side effect of forcing runways to be 30 tiles or so long is that planes take over half a minute of real time to taxi down this length of runway. Even time taken to take off and land (demanding full use of runway) will be 10 seconds or so at least.

Well, you should still place the runways in such a way that the aircrafts only taxi one field on the runway after landing and before take-off.
Even though I am heavily using city airports in my games, airports which typically just take 9 fields, and some industries even have their own airports because they are so extremely cheap (compared to a 100 tile railway track), I am actually looking forward to this

This likely only works due to the incredible ability of japanese to sleep anywhere and for any time, when they have a chance to do so.

Hmm, Ive been doing this on a rather regular basis. All those bus companies apparently have customers, who dont care how they get around in europe as long as its cheap. The only problem with sleep Ive had, was the police

[Carl]

FWIW, here's what a realistically-proportioned Heathrow looks like on my 118-meters-per-tile GB map. Given the similarity in scale, this is the kind of scale airports will have to be on in the new version of pak128.Britain. The runways are 3.9km -- 30 tiles -- long.

[Milko]

Oops - almost forgot to reply to this. I don't think that the runway lengths would be too long: as Carl says, long runways are realistic. In fact, the next version of Pak128.Britain-Ex will have 125m/tile, so the runways will be even longer: a 3.5km runway will be 28 tiles long. This will, as Carl points out, force people to put down realistic airport infrastructure, and make airports more resource intensive (and less suitable to be placed very near cities) than they have been in Simutrans in the past. This is a good thing, I think.

Assuming that the size (in tiles) of the airport does not vary with change in km / tiles while the length of the runway would vary with the variation of parameter, it would better define the minimum length of the track using the tiles in place that km?

If you want to test it, however, you will need not only the latest -devel makeobj, but a binary build from the latest -devel branch, as the existing release candidate is too old to be able to read files written. I can upload these for you if you'd find that helpful?

I only need yhe makeobj.

Thank's
Giuseppe

[el_slapper]

125m per tile? mmmh, if I want to simulate my favorite travel, Paris to Wroclaw(family of my wife), 1400km, it would be, errr, 1400*8=11200 tiles. that's not even a big travel. Buses do the travel in 18 hours for a 70 €uro ticket. Wizzair makes it slightly costlier, but that's only 2 hours of flight(plus one hour to get to Beauvais airport from Paris).

Of course, I guess the idea is to simulate Britain alone. Are there many flights other than London-Manchester-Edinburgh-Glasgow-Dublin in British islands?

Google maps tells me London-Glasgow is 402 miles - 643 km. That's already more than 5000 tiles. I need to repair my 8-cores computer if I want to play that..... and the map does not even link northern scotland. Isn't 125m/tile a little overkill, at least with current computers?

[jamespetts]

Interesting discussions, although this is now rather more about scale generally than airports per se!

Firstly, on airports themselves: SDog's screenshot is quite something - it would be most exciting to see something on that scale actually being used for real in an online game. As to the timings within an airport, that should all be realistic enough if aircraft taxi at realistic speeds (which I think that they do - if not, that can easily be fixed). Don't forget that, with every reduction in the meters per tile setting, the game minutes (for travel time purposes) per real life seconds reduces proportionately so that the same number of game meters is covered in the same number of game minutes.

As to map sizes generally, to simulate both local urban transport (which ought not be forgotten in all this discussion about airports - urban rail and 'bus networks with a high scale setting are very fun!) and air/sea transport properly at the same time, large map sizes are indeed required. Large maps are more practical than people seem to think, however. The current Simutrans-Experimental server game has a map with dimensions of 1724x2816 (using 250m/tile, the then default setting) and 675 towns (I think that a player manually founded a new one, as the total is now 676). Once a number of bugs/issues had been fixed in Experimental, performance was perfectly acceptable on that map for all but quite elderly computers even when it got to a very high level of intense development in the 1970s and onwards, and that was with the physics engine as it was in 10.11: Bernd has made the physics calculations (which were previously one of the more demanding elements of the game) much more efficient for the new release.

What really makes a difference to performance is not the raw size of the map (which only affects memory consumption, rather than processor use or memory bandwidth, and memory is not expensive these days), but the intensiveness of the network, which, in turn, depends on the number and size of towns and industries and the number and level of activity of the players. So, doubling the map size whilst retaining the same number of cities will not significantly adversely affect performance except during the initial map generation, which is done once and need not be repeated. Indeed, for an online game, this is done once by the server administrator, so is entirely transparent to the end user in any event.

There are two further tricks for maximising the distance of long distance travel whilst not putting too much demand on peoples' CPUs. One is, as SDog suggests, to have a long and thin map, which is two or even three times as wide as it is high. The other is to have a large area of ocean in the middle of the map, enabling long journeys (by sea or air) but without having much that consumes CPU cycles or memory bandwidth for large areas of the map that have to be traversed.

For example, map no. 1532 (on Experimental) with a West to East dimension of 5,632 tiles (704km) and a North to South dimension of 2048 tiles (256km) and a water level of -1 or even 0 gives a good "ocean in the middle" effect. One could similarly try map no. 68 with dimensions of 5760 x 2048 (720km x 256km) with a water level of -1. (Both have mountain height set to 160 and map roughness to 4). Incidentally, the size in memory shown is the uncompressed size - one need not worry about having to send over a gigabyte down the network: the compressed size is a mere 8.7Mb (and this is with a full complement of trees - I need to thin out the forests a little, I think). Map no. 680 also looks promising with a water level of 0 (this is my favourite so far, I think).

Getting the map generator reliably to produce maps with large central oceans is a rather hit and miss business, so another approach might be to get a very large height map either of an actual region in the world that is appropriately configured or create one with the appropriate shape(s) of land mass(es) to suit the requirement.

Giuseppe - are you sure that you want just Makeobj? No version of Simutrans-Experimental ever released in binary form can read the files generated by the latest -devel version of Makeobj, and the latest -devel version of Simutrans-Experimental is required to read them. I have put both Makeobj and the executable into this .7z file for you.

Edit: With no trees at all, the 5760 x 2048 saved game (with no infrastructure and 16 cities) is reduced to just over 1Mb in compressed size.

[kierongreen]

Great Britain at 125m/tile needs in the region of 8000x4500 tiles (if you rotate it a little - you get some islands on it as well, but not all of Ireland). At least in simutrans standard maps should have less than 16.7m tiles, and at 36m tiles this is too big for standard. This limit is mainly imposed by how labels are stored and rotated I think, so if you exceed it then as long as you are prepared to deal with this it's not a huge problem. You will notice this if you rotate the map, or if you mange to build two stations such that y1*map_width+x1 = y2*map_width+x2. Of course, you could alter the way labels are stored to get round this in experimental.

Playing a map 5000 tiles long isn't a problem, as long as the overall tile count isn't too big, e.g. 5000x1000 should be perfectly playable on an 8 core machine (with standard 4000x3000 or so is just about playable later on in the game on a dual core atom).

Of course, just because physics are by default set to 125m/tile doesn't force you to play at exactly this scale though. You can adjust this value, or just use a smaller map to represent the same area anyway.

Having tested the size of airports myself (and seen carlbakers excellent screenshot) I have to say large airports do look nice though

Are there many flights other than London-Manchester-Edinburgh-Glasgow-Dublin in British islands?

Great Britain to Ireland (most airports in Great Britain to Dublin or Belfast) has a fair few flights and is generally the quickest and most convenient way to travel. London - Scotland is the only major traffic route within Great Britain where air travel has a real advantage, though if you are connecting to onward flights at Heathrow or Gatwick then flights from Manchester, Leeds or Newcastle to London might make sense.

[jamespetts]

I have known people flying from London to Manchester.

Things rather do all have to be to a consistent scale, however, as all the distances between stops, the journey times and the waiting times (and journey times, in turn, are linked to appropriate comfort levels) are all linked into the meters per tile scale as well as the actual physics (stopping/accelerating distances, etc.), so that the relationship between things like dwell time and journey time or airport minimum waiting time and speed, etc., are all fixed to the scale. The whole point of having a larger map is to enable simulation of long distance as well as short distance journeys in the same map.

One way of allowing larger ocean areas would probably be to tinker with the map generation settings so as to alter the scale there: this has already been done once for Experimental, and could without much difficulty, I think, be done again so as to have less fussy maps on that larger scale which would have a greater chance of having a large central expanse of (nearly free, in computational terms) ocean to allow for long distance journeys as well as local transport.

[kierongreen]

I have known people flying from London to Manchester.

Likewise I've known people fly from Manchester to Scotland. Over these sort of distances train travel makes more sense really though, unless you happen to be near the airport in both places. Mind you, most people would probably drive these days anyway :(

[Carl]

Likewise I've known people fly from Manchester to Scotland. Over these sort of distances train travel makes more sense really though, unless you happen to be near the airport in both places. Mind you, most people would probably drive these days anyway :(

Depends where in Scotland! Manchester -> Aberdeen is 1.25 hours by plane, but can be 7 hours by train! And often similar costs...
(sorry, off-topic!)

[kierongreen]

This was Manchester to Glasgow! If you are travelling from anywhere north of the central belt in Scotland to England you are usually better off flying in terms of time, assuming there are flights available. Also flights from Aberdeen (I'm thinking Eastern Airways here) can be very expensive

[prissi]

Also flights shorter than 150 km are very common on islands, like in the caribbean (for instance Purto Rico to American Virgin Islands), or between the Hawaii islands. One of those company used really vintage 737, which were still not logging enough flight hours to be disposed, because they only flight less than 40 min for each leg.

Wikpedia say: "Aloha Airline's longest inter-island route was 216 miles, while the shortest route was a mere 62 miles. Average travel distance per inter-island flight was 133 miles."

[Milko]

Also flights shorter than 150 km are very common on islands, like in the caribbean (for instance Purto Rico to American Virgin Islands), or between the Hawaii islands. One of those company used really vintage 737, which were still not logging enough flight hours to be disposed, because they only flight less than 40 min for each leg.
Wikpedia say: "Aloha Airline's longest inter-island route was 216 miles, while the shortest route was a mere 62 miles. Average travel distance per inter-island flight was 133 miles."

Finding (google) "aloha airlines flight 243", contains a description of a plane crash due to excessive number of departures per day that the aircraft suffered. Too many daily flights of short duration ...

@James
The airplanes will rise from the ground after covering the tile set in the file ".dat" or the aircraft will walk accross the runway?
The acceleration of the aircraft will be phased in starting and take-off or a good part of the track will be flown at a constant speed?

Giuseppe

[jamespetts]

Giuseppe,

I have not done anything with aircraft physics yet, but I do plan to make what looks like it will be a simple modification of making the aircraft's rotate point when taking off the same as its minimum runway length, so that players are not baffled when they are forced to lay a long runway, but aircraft only appear to use a small part of it.

Edit: I have been doing some tinkering on the -devel branch - map no. 2147483642 works quite well with the new settings.

[Milko]

Hello

The new features are:
(1) aircraft all have a minimum runway length in meters, and cannot take off/land from a runway shorter than that length; and
(2) all airports must have control towers.

Next step: Airplane Range?

Giuseppe

[jamespetts]

I have considered range; however, it is a tricky issue. It would apply not just to aircraft, but rail and road vehicles, too, as well as ships, and, indeed, almost any non-electrified vehicle. The trouble is that it is not an easy thing to communicate to a player: whilst actually stating the range in the depot/replacer window is easy enough, players actually being able to work out whether any route will be in range of suitable vehicles before planning it is not an easy task. I suspect that people would find this feature a bit too awkward and fiddly.

I might take a different view if there seems to be overhwelming support for it, but it would also be much more tricky to programme than runway length restrictions, and would fall to take a lower priority to a number of important outstanding issues such as increases in vehicle maintenance with usage, overhauls, way upgrading costs, and so forth.

[kierongreen]

Also on the scale of simutrans maps range isn't an issue as it would be larger than the map...

[sdog]

it would be also a bit difficult to decide what to do with a plane, when it runs out of fuel.

limiting the routefinding before it starts is also not an easy option, since waypoints might be very exploitable in this regard. Short flights and endless circling would also not be covered.

I don't think it would be uncalled for if only planes would be limited in range by fuel.

It is a non issue for ships, you can just pack enough to reach any destination port. Road vehicles could just fill up unnoticed, as could diesel or steam trains. The infrastructure required is minimal.

[Vladki]

refilling of trucks and trains, could be done as special station extension. It was this way in railroad tycoon, whre you had to build water tower and sand tower at least in hub stations. If you didnt your trains ran out of steam and sand and moved veeeery slooowly.

[ӔO]

One thing that might be worth consideration: variable running costs with acceleration/deceleration and constant velocity.

[el_slapper]

Range is really somthing that would kill the gameplay for not much impact. Especially on Experimental where the scale is small, & the biggest you can simulate is the British Islands. Truck stops & refuels, other vehicles have far more autonomy than the size of the map.

having refueling stations would horribly clutter the map with little impact on realism or gameplay experience. I vote no. Interesting problems are worth solving, like infrastructure size depending on the vehicles used - and that's exactly the purpose of long runways.

Railroad Tycoon had far less things on the maps, and far less things to do for the player. Lay tracks, add refueling stations, run the train. Even like that, it was rather boring to add refueling stations in the middle of the sahara. You are dead if you don't add them, but there is not much strategy in adding them : you put them when the loco runs out of steam/sand. Not an interesting decision. Choosing wether I will use airplanes or trains between London & Manchester, and building according airport/railroad IS interesting, OTOH.

[isidoro]

Well, there was some strategy involved in placing sand/water stops since they cost money.  Similar to placing depots in ST.

[sdog]

It is a little different for planes though, as it might restrict the choice of some planes for some conexions.

What would be the shortest range any of the planes included or planed for the pak has?

The longest distance would be less than 1000 km. Going diagonal on a 6000 tile square map (6k*1.4=8k) would provide that, or a 8000 tile elongated map. That is quite a lot at this time.

A Cesna 172 has about 1000 km range. That's about as small one could get with a modern aeroplane.

It might matter for historic planes, early Hadley-Page 'planes were flying Croydon to LeBourget, 350 km. I should guess they were designed specifically for this and it might be about the maximum possible. On the other hand, the customer would have changed the requirements, so the range always would have covered the distance required.

[o_O]

No matter how big the map gets, realistically most large aircraft traffic would still be to and from off map locations.  It might make sense to add abstract international destinations to allow realistic airport sizes, passenger levels and transportation requirements while only modeling a smallish region.  So you schedule your Airbus A380 to fly to Shanghai twice a month, but really it just flies off the map then re-appears a while later with new people who want to go someplace.  This way you could have huge, busy airport hubs without specially designing gigantic maps or fudging the airplane numbers.

Although I don't know how well the code could accommodate this. 

[jamespetts]

o_O,

actually, I have been considering this idea recently. The way that it might work, I think, is to have special tiles that, when set as a destination, allow a ship or aircraft to travel a designated distance off map, load and unload passengers/mail/cargo of specified types in a fixed time, and return to the point again in a calculated time. The vehicle itself would calculate its speed and loading/unloading time as normal, and the distant port/airport would be represented as an actual stop, but the actual distance between it and the special tile would not be represented by part of the actual game map. These special tiles could be highlighted red (for example) and be restricted to being water tiles on the map edge. Players could see all vehicles in transit on the relevant overseas route by clicking the tile, and would be able to see the convoys as normal, just with a black background instead of an actual slice of the map in their pictorial window. This would indeed allow simulation of international transport within sensibly sized maps.

This should be reasonably possible to accommodate in the code, but would still probably be a rather large amount of work. It is not currently a priority for my coding work, as I am concentrating on balancing (and possibly merging the latest Standard features) for the release after next (the next release being a matter of bug fixing and testing) of Experimental, but this is something to bear in mind, I think, for one day in the future.

However, if anybody else would like to code this, that would considerably expedite the process.

[ӔO]

one could just paint up a complete airport as an attraction.

[jamespetts]

Yes, that's another method that I've considered in the past. Both have their advantages. The advantages of the airport as attraction method are that it takes far less work to code (although actually producing a graphic for a full sized airport would be quite a challenge).

The main advantage of the overseas transport tile method is that it allows actual simulation of long distance travel, which is not currently possible in Simutrans (practically), and is an interesting thing to simulate, especially with a good range of aircraft. It's really a matter of balancing one against the other.

[isidoro]

Conceptually speaking, what is the difference between such special tiles and industry or attraction stations with an increased loading time (simulating the round trip off the map)?

I say that because maybe that is a not so difficult way of programming it...

[jamespetts]

Conceptually, the difference is that, with the special tiles, players actually have to manage and control international transport. With attractions/industries coded as ports/airports, international transport is assumed, rather than simulated.

[Carl]

Yes, that's another method that I've considered in the past. Both have their advantages. The advantages of the airport as attraction method are that it takes far less work to code (although actually producing a graphic for a full sized airport would be quite a challenge).

The main advantage of the overseas transport tile method is that it allows actual simulation of long distance travel, which is not currently possible in Simutrans (practically), and is an interesting thing to simulate, especially with a good range of aircraft. It's really a matter of balancing one against the other.

I don't see these methods as mutually exclusive.

[ӔO]

personally, I don't see a need to allow players control over international, off map, transport.

[sdog]

The airport attraction method is too much of a hack. Possibly unbalancing the attraction system, by having one mega-attraction. Also if there was only one, a single player could effectively claim it in multiplayer, gaining a massive advantage.

Have you asked simutrans standard, if there was a desire to have a long-range connection point on the edge of the map? I wouldn't be too surprised if there was a strong desire, (and a steep potential barrier of opposition to overcome) but it might be sensible to ask at least. Some brainstorming on how this would have to be implemented, such a sink/source needs proper self balancing attributes, might also be helpful.

[Carl]

The problems sdog raises don't seem insurmountable. The passenger level could easily be balanced relative to other attractions in the pakset. And in network games there could be a rule that airport stops/stations must be public.

[jamespetts]

Whilst the two methods are not technically incompatible, it seems to me that it would be very odd and confusing for players if two very different ways of representing the same thing were used simultaneously in the game; I don't think that that would be desirable at all. It would be fun indeed to simulate long distance overseas transport, but the question is one of practicalities.

Aside from the issues as to the coding of it, a further thought has sprung to mind as to a potential difficulty: in the days of sailing ships, it could often take many months to reach a destination. On the basis that there are 720 hours in a month, a four month journey would last 2880 hours. On the basis that there are just under three and a quarter travelling hours in every Simutrans game month, the journey lasting four months in real world time would take just over 886 years in compressed Simutrans time, which would clearly not work. For aircraft with journey times of not more than 24 hours, this would be less of a problem, but even a 20 hour journey would last over six game months in Simutrans-Experimental.

[Carl]

Whilst the two methods are not technically incompatible, it seems to me that it would be very odd and confusing for players if two very different ways of representing the same thing were used simultaneously in the game; I don't think that that would be desirable at all.

One need not think of them as representing the same thing. Most pertinently, airports generate high levels of retail and service employment, which generates a lot of traffic to and from airports. As such we should not expect travel to airports to be exhausted by those who are getting on planes. If simulated off-map air travel were to be introduced, one could think of the "attraction" role of airports to be limited to traffic of airport staff, etc.

[jamespetts]

Wouldn't that be even more confusing, as players would expect that people would go to international airports for both reasons? Indeed, it's rare for people to go to airports if they don't actually want to use the airports as airports - the shops and things are generally no better than on a high street and are intended for and used by air travellers.

[Carl]

I was mainly talking about employees, not shoppers. Employment levels at and around airports are such that there are often transport links which are put on especially for the purpose of getting workers there. Even commercial links owe a significant portion of their ridership to airport employees. Whenever I've used the East Midlands Airport buslink from Nottingham, for instance, a significant amount of passengers were airport workers with season passes rather than travellers with suitcases.

An example: a quick search reveals that Stansted employs over 10,000 people. That's a lot of non-flying traffic.

[jamespetts]

Ahh, I see what you mean about employees. Still, I do think that it'd be confusing and counter-intuitive to have airports as attractions just for their employment rather than their international passengers.

[jamespetts]

The airport improvements discussed herein are now in version 10.12 of Simutrans-Experimental, released to-day.