Author Topic: Airplane passengers only going one way  (Read 386 times)

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Offline passengerpigeon

Airplane passengers only going one way
« on: June 18, 2017, 07:41:33 AM »
Dear community,
Recently, I built airports in several major cities on my map (20,000+ inhabitants) and linked them to the downtown train stations, and hence the city transit networks, with non-stop double-decker buses. However, every flight I tried to run was packed for the journey from A to B and empty for the flight back to A, which prevented me from making any profit, and when I set the plane to wait for a full load at B, it took several months to fill and A airport was overcrowded by the time it landed there. How can I make sure flights are full in both directions? Do I need to link several cities to a central hub?
Thank you,
Passengerpigeon.

Offline Ters

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Re: Airplane passengers only going one way
« Reply #1 on: June 18, 2017, 12:58:15 PM »
For every passenger going from A to B, there will be a passenger going from B to A. I the stop at B is overcrowded, that passenger is however unable to start the journey and will die.

Another problem causing uneven passenger flow on a line is having even-edged loops (A-C-B-D-A) in your network. If there are two possible links between A and B with an equal number of transfers, you may find that passengers select one link (A-C-B) for the journey A to B and another link (B-D-A) for the journey B to A. I therefore try to keep the loops in my network odd-edged (A-B-C-A).

It might also simply be that many of the passengers going A to B is going much further than to B. The majority of the return passengers simply haven't made it to B yet.

Offline passengerpigeon

Re: Airplane passengers only going one way
« Reply #2 on: June 18, 2017, 01:49:59 PM »
OK, so I started two air routes and monitored the airports to make sure that none of them became overcrowded. On my first air route, I initially got enough passengers to fill a Concorde in both directions, but then the passengers mysteriously petered out despite neither my airports nor the shuttle buses to the train station being overcrowded. On the second air route, my RVG 747D still flew almost empty one way and full the other. Do all cities with over 20,000 people generate enough passengers between one another to support an air route, or do I have to look for specific city pairs?
Also, with regards to connections, all of my air routes duplicate a direct (but obviously slower) train service - is this really drawing away passengers? I just noticed your point about passengers travelling onwards and will try the air routes again for a longer period of time - since the only way to get to the airport is via the train station, are the overcrowded train stations eating returning passengers?
« Last Edit: June 18, 2017, 02:16:30 PM by passengerpigeon »

Offline Ters

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Re: Airplane passengers only going one way
« Reply #3 on: June 18, 2017, 02:43:41 PM »
Overcrowding only causes passengers to "die" when it is the initial stop that is crowded. At least with default settings. (I think passengers also die if you send the vehicle they are on into a depot.)

Having a train line serving the same route as the airplane sounds like an even-edged loop situation. You should then see a corresponding asymmetry on the trains.

As long as you wait for a full load, any size should do. Passengers both ways are generated simultaneously, so when every other problem is eliminated, there will be just as many passengers waiting to board as just arrived.

Offline DrSuperGood

Re: Airplane passengers only going one way
« Reply #4 on: June 18, 2017, 06:09:53 PM »
Quote
For every passenger going from A to B, there will be a passenger going from B to A.
Only for long distance or industry passengers. Local passengers do not spawn return traffic.

A big cause of asymmetric traffic is the black hole transfer problem when no transfer restrictions are in place. Potentially millions of passengers can be swallowed by such a transfer stop meaning that millions are missing from one direction of a journey. A black hole transfer occurs when more people are being put into a stop by transfer than are being pulled out of the stop. Very common in multiplayer games when someone who mismanages their passenger network ends up with a transfer holding millions of passengers destined for a public stop.
« Last Edit: June 18, 2017, 09:42:57 PM by DrSuperGood »

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Re: Airplane passengers only going one way
« Reply #5 on: June 18, 2017, 06:39:28 PM »
Local passengers do not spawn return traffic.

I've never heard that before. But the asymmetry in industry-generated mail also came as a surprise. However, I assumed A and B to be different cities, and that isn't local traffic, or is it?

A big cause of asymmetric traffic is a black hole transfers when no transfer restrictions are in place. Potentially millions of passengers can be swallowed by such a transfer stop meaning that millions are missing from one direction of a journey. A black hole transfer occurs when more people are being put into a stop by transfer than are being pulled out of the stop. Very common in multiplayer games when someone who mismanages their passenger network ends up with a transfer holding millions of passengers destined for a public stop.

Doesn't this give warnings about crowded station? And I got no indications that this question was about a multiplayer game. In any case, it is sort of a case of delayed passengers.