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Busses get tiny subsides in the US. It’s a large percentage of total bus revenue by design, and a significant expense for some local governments. But the num

by Retric 8mo ago

Busses get tiny subsides in the US. It’s a large percentage of total bus revenue by design, and a significant expense for some local governments. But the number only look large because of how we split the vast majority of government spending into federal and state budgets with local budgets being relatively anemic by comparison.

iamcalledrob 8mo ago
The farebox recovery ratio in the US is awful. Most cities are somewhere between 5-25% of operating expenses coming from fares. Perhaps the tiny subsidies (in absolute terms) are because the bus systems are just so small? SFMTA's farebox recovery is around 25%. London Underground is about 130%. Osaka Subway is 209%. https://en.wikipedia.org/wiki/Farebox_recovery_ratio https://en.wikipedia.org/wiki/Farebox_recovery_ratio
philwelch 8mo ago
Buses are implicitly subsidized by road maintenance spending. Road wear and tear occurs according to the fourth power of axle weight, which effectively means almost all of the wear and tear is incurred by the heaviest vehicles, which include buses.
- Retric 8mo ago
  Roads still need maintenance even if nobody uses them, so a significant portion is split evenly across all traffic. Busses are light compared to 18 wheelers and other heavy equipment, they also replace many cars and SUV’s which keep getting heavier. Finally that rule of thumb isn’t really that accurate, “A 1988 report by the Australian Road Research Board stated that the rule is a good approximation for rutting damage, but an exponent of 2 (rather than 4) is more appropriate to estimate fatigue cracking.” Rutting really isn’t that significant in most cases, but can instantly destroy road surfaces when fully loaded construction vehicles etc drive over something once.
  - philwelch 8mo ago
    > Busses are light compared to 18 wheelers and other heavy equipment, they also replace many cars and SUV’s which keep getting heavier. They don’t replace nearly enough cars and SUV’s to make up for the difference in fourth power of axle weight. But yes, 18 wheelers are worse.
    - xnyan 8mo ago
      >They don’t replace nearly enough cars and SUV’s to make up for the difference in fourth power of axle weight A modest bus holds 40-50 people. Most commuter traffic is single driver, single vehicle. I don't know to which power the difference in axle weight would have to be to surpass the efficiency gains of replacing 40 to 50 American sized SUVs with a city bus, but I suspect it's more than four.
      - XCabbage 8mo ago
        At the heavy end, SUVs weigh about 3 tonnes, while at the light end buses weigh about 12, a 4x difference. 4^4 = 256. So if the claim about the fourth power is true, you'd need to replace 256 SUVs to break even on wear, which is obviously impossible. (I don't really understand how the fourth power of axel weight thing can possibly be true, though. Why would joining two vehicles together into a mega vehicle with double the weight and double the wheel count suddenly cause the combined vehicle to inflict 16x more wear than before you joined the two together? It makes no sense.)
        rkangel 8mo ago
        Joining two vehicles together with double the weight and double the axle count does not change the load on each axle. So, scenario A: 4 ton vehicle, 2 axles load per axle is 2 tonnes. 2^4 is 16 2 axles - so load is 32. Another vehicle the same - also loading 32 Total: 64 Scenario B: 8 ton vehicle, 4 axles load per axle is 2 tonnes 2^4 is 16 4 axles - load load is 64 Total: 64
- adgjlsfhk1 8mo ago
  Axle weight and vehicle weight aren't the same (or even very closely correlated). A bus will weight ~3-4x more than a car, but has wider tires, and carrying far more people. As such the weight of a bus is likely similar to or lower than an equivalent number of cars.
  - coryrc 8mo ago
    Wider tires do not reduce axle weight. Here in Seattle, the busy roads with older lanes used for buses are obvious, because they have two deep canyons while the lane next to them is fine. In fact King County Metro has to pay millions in fines to the state because the buses are excessively heavy. No roads without bus traffic have the same type of damage.
    - adgjlsfhk1 8mo ago
      > Wider tires do not reduce axle weight. Which is part of the reason to know that axle weight alone isn't a sufficient scale. If you connect 2 cars axle to axle, they won't start doing 8x as much damage. What matters is axle weight divided by tire width.
      - coryrc 8mo ago
        Nope, that's not correct, except that two cars would be spread across two lanes. PSI is not the only factor. Take, for example, our concrete road panels here in Seattle. The weight on one end forces that side of the panel down, stressing the connection to the previous panel, and also lifting the panel from the front. That force is not significantly changed by tire width. I wish you did a little more studying before talking so authoritatively.

by Retric 8mo ago

iamcalledrob 8mo ago

The farebox recovery ratio in the US is awful. Most cities are somewhere between 5-25% of operating expenses coming from fares. Perhaps the tiny subsidies (in absolute terms) are because the bus systems are just so small? SFMTA's farebox recovery is around 25%. London Underground is about 130%. Osaka Subway is 209%. https://en.wikipedia.org/wiki/Farebox_recovery_ratio https://en.wikipedia.org/wiki/Farebox_recovery_ratio

philwelch 8mo ago

Buses are implicitly subsidized by road maintenance spending. Road wear and tear occurs according to the fourth power of axle weight, which effectively means almost all of the wear and tear is incurred by the heaviest vehicles, which include buses.

Retric 8mo ago
Roads still need maintenance even if nobody uses them, so a significant portion is split evenly across all traffic. Busses are light compared to 18 wheelers and other heavy equipment, they also replace many cars and SUV’s which keep getting heavier. Finally that rule of thumb isn’t really that accurate, “A 1988 report by the Australian Road Research Board stated that the rule is a good approximation for rutting damage, but an exponent of 2 (rather than 4) is more appropriate to estimate fatigue cracking.” Rutting really isn’t that significant in most cases, but can instantly destroy road surfaces when fully loaded construction vehicles etc drive over something once.
- philwelch 8mo ago
  > Busses are light compared to 18 wheelers and other heavy equipment, they also replace many cars and SUV’s which keep getting heavier. They don’t replace nearly enough cars and SUV’s to make up for the difference in fourth power of axle weight. But yes, 18 wheelers are worse.
  - xnyan 8mo ago
    >They don’t replace nearly enough cars and SUV’s to make up for the difference in fourth power of axle weight A modest bus holds 40-50 people. Most commuter traffic is single driver, single vehicle. I don't know to which power the difference in axle weight would have to be to surpass the efficiency gains of replacing 40 to 50 American sized SUVs with a city bus, but I suspect it's more than four.
    - XCabbage 8mo ago
      At the heavy end, SUVs weigh about 3 tonnes, while at the light end buses weigh about 12, a 4x difference. 4^4 = 256. So if the claim about the fourth power is true, you'd need to replace 256 SUVs to break even on wear, which is obviously impossible. (I don't really understand how the fourth power of axel weight thing can possibly be true, though. Why would joining two vehicles together into a mega vehicle with double the weight and double the wheel count suddenly cause the combined vehicle to inflict 16x more wear than before you joined the two together? It makes no sense.)
      - rkangel 8mo ago
        Joining two vehicles together with double the weight and double the axle count does not change the load on each axle. So, scenario A: 4 ton vehicle, 2 axles load per axle is 2 tonnes. 2^4 is 16 2 axles - so load is 32. Another vehicle the same - also loading 32 Total: 64 Scenario B: 8 ton vehicle, 4 axles load per axle is 2 tonnes 2^4 is 16 4 axles - load load is 64 Total: 64
adgjlsfhk1 8mo ago
Axle weight and vehicle weight aren't the same (or even very closely correlated). A bus will weight ~3-4x more than a car, but has wider tires, and carrying far more people. As such the weight of a bus is likely similar to or lower than an equivalent number of cars.
- coryrc 8mo ago
  Wider tires do not reduce axle weight. Here in Seattle, the busy roads with older lanes used for buses are obvious, because they have two deep canyons while the lane next to them is fine. In fact King County Metro has to pay millions in fines to the state because the buses are excessively heavy. No roads without bus traffic have the same type of damage.
  - adgjlsfhk1 8mo ago
    > Wider tires do not reduce axle weight. Which is part of the reason to know that axle weight alone isn't a sufficient scale. If you connect 2 cars axle to axle, they won't start doing 8x as much damage. What matters is axle weight divided by tire width.
    - coryrc 8mo ago
      Nope, that's not correct, except that two cars would be spread across two lanes. PSI is not the only factor. Take, for example, our concrete road panels here in Seattle. The weight on one end forces that side of the panel down, stressing the connection to the previous panel, and also lifting the panel from the front. That force is not significantly changed by tire width. I wish you did a little more studying before talking so authoritatively.