a future for very very long buses?

I've repeatedly said that if you need a high capacity vehicle with just one driver, over a sustained period of time, you probably have a good reason to build rail.  Rail's ability to expand vehicle size through multiple cars, without adding staff, is one of the ways it works well on the bottom line.

But now we're seeing some really, really long buses:


Are there limits to the length of the bus that do not apply to rail?  Yes, though it's easy to imagine cases where they wouldn't apply, such as median busways where the bus never has to weave to access a stop.  In ordinary operations with curb stops, I suspect that we won't see buses grow much longer, and there is even interest in replacing the articulated (single-bend) bus with double-deckers, in the London manner, to use urban curb space more efficiently.  

24 Responses to a future for very very long buses?

  1. fozzy September 26, 2012 at 2:56 pm #

    In France there are some BRT with 24m long busses with two articulations (18m for a single articulation bus, 12m without articulation). The one on the picture might be 30m long.
    However, I doubt there is a big future. Alstom and CAF launched small tramways (Citadis Compact and Urbos3) that are also only 24m long.
    New tram projects are getting quite cheap in small french cities (arround 15M€/km), so the price gap between a properly separated bus corridor and a tram is getting smaller, even for lines with less than 20’000 passengers/day.
    I’m curious to see what will

  2. Neil September 26, 2012 at 3:36 pm #

    Anybody have experience with double articulations in traffic? Seems like a good idea for BRT applications with at least dedicated lanes (ideally a separated corridor) and pay-at-station ticketing, but wouldn’t have enough maneuverability for use on busy city streets (and way to slow to load if you insisted on having the driver collect payment.)

  3. Michael D. Setty September 26, 2012 at 4:52 pm #

    Also, does anyone know how the French manage to keep their prices down for new tram projects, particularly in contrast with new U.S. projects, which seem to average 50%-150% more per mile/kilometer?

  4. NCarlson September 26, 2012 at 5:00 pm #

    I’d definitely like to see some kind of demonstration of double artics in an American environment. I agree that in general their applications are fairly limited, but can think of several instances where for one reason or another rail just doesn’t make sense (or work at all) but the capacity would be very useful. They aren’t something I would expect to ever see all over the place, but I don’t think the niche for these things is necessarily all that small either.

  5. Miles Bader September 26, 2012 at 8:22 pm #

    There are no doubt places where it makes sense, but while getting longer may give buses some of the advantages of rail, it also gives them some of the disadvantages of rail.
    In particular, very long buses won’t have the routing flexibility of shorter buses.

  6. JJJ September 26, 2012 at 8:33 pm #

    “but wouldn’t have enough maneuverability for use on busy city streets” Why not? The swiis maneuver their bi-artics on very narrow roads. Thats the whole point of the articulation…if the front section if 40 feet long, then its just as easy to maneuver as any 40 foot bus.
    The only issue is that bus stops must be longer.
    “and way to slow to load if you insisted on having the driver collect payment.”
    Only an american transit system would be foolish enough to do this. Most european systems let you board through any door.
    Id like to see this bus from the other side…wonder how many doors it has. American transit systems are terrified of doors for whatever reason.

  7. Oliver September 27, 2012 at 12:43 am #

    Zurich has bought some trolley buses with double articulation for their high traffic volume lines.
    They carry 128 passengers and run on normal streets. Drivers have to do an additional training due to the close to 25 meters length.
    The two lines needed some adaptions for stops and curves (e.g. moving signals), but these were minimal.

  8. teme September 27, 2012 at 4:40 am #

    In most cases, I fail to see the point. Rail vehicles are not expensive because there is something inherently costly about manufacturing them, but because building it is a low volume niche business. Just as building double articulated buses is. Special busses have special prices. Why not just build rail if there is sufficent demand?

  9. Philip September 27, 2012 at 4:44 am #

    I’d add that biarticulated motor buses are also used on at least one route in Luxembourg, but I think that route runs only over relatively wide/straight roads.
    But I agree that for most cities, buses of that length will be limited to totally segregated busways, and if you’re going to build one of those you might as well go with the superior ride and lesser rolling resistance of rail.

  10. Philip September 27, 2012 at 4:47 am #

    I’d also add that the problems with very long buses aren’t just down to curves and the kerb length taken up by stops. The articulated buses in London also had problems in heavy traffic at crossroads, when the green phase of the traffic light sometimes wasn’t long enough for a space on the other side of the junction long enough to contain the bus to form, so the drivers were faced with either never getting across the crossroads, or obstructing traffic crossing the junction at 90 degrees.

  11. Tom West September 27, 2012 at 6:28 am #

    Are there any double-decker articulated buses in general use?

  12. Jonathon September 27, 2012 at 7:05 am #

    Take note of Ottawa’s situation- having a grade-separated busway system that relies on street-running HOV lanes through the city core, bus congestion is so bad (approximately 200 buses/hour in each direction) that the city is buying double deck buses instead of articulated buses to conserve road space until the LRT tunnels are built.

  13. Eric Doherty September 27, 2012 at 10:21 am #

    The City of Vancouver has asked the provincial government to change the regulations to allow longer buses (They have already been changed to allow longer trucks, even on crowded city streets).
    I think these longer buses have a big future, particularly in combination with dedicated transit lanes and full on bus rapid transit lines. And if it a line is busy enough to justify big buses, then it is probably busy enough to justify using electric trolley buses to reduce noise, pollution, GHGs, and to increase acceleration.
    In Canada a big question is snow performance; the Swiss deal with this issue with multiple electric drive units on double articulated buses and I assume the German bus referred to in the link does too. Snow performance might be better with these double articulated buses than with the existing diesel single articulated buses with only one drive axle at the back.

  14. Max Wyss September 27, 2012 at 3:24 pm #

    The main problem with such big (and heavy) buses is to provide sufficient power for traction, but also for auxiliary equipment (air condition etc,). Therefore, having such a vehicle as trolley bus would be preferable.
    However, the original article claims that the vehicle can run on battery power, which makes me assume that the drive would actually be diesel-electric. Under this premise, it would be possible to use a higher rated diesel engine (there are truck engines with 500 kW and more), and have electric propulsion.
    As it has been stated, Zürich (and Genève and St.Gallen) have 25 m long double articulated trolleybuses in regular street operation (with some rather tight curves). There seems to be not much of a difference to the standard articulated (trolley)buses.
    Why a high volume double articulated bus and not a streetcar? Such a bus can become operational within months, whereas a streetcar line will take a few years to become operational.

  15. al September 28, 2012 at 9:27 am #

    The bus prototype is built with multiple steerable axles. The wheels follow one another around a curved virtual track. The builders, Fraunhofer IVI, have another vehicle that demonstrates this capability as well.

  16. Dexter Wong September 28, 2012 at 4:14 pm #

    As for double-decker articulated buses, I don’t know of any today, but thirty years ago, the German firm Neoplan had quite a few models. One toured the USA being demonstrated as a rolling hotel.

  17. Henry September 29, 2012 at 4:11 pm #

    Yikes. That thing looks like it would get in serious trouble in the event of a crash.
    This is probably when it starts making more sense to install a tram.

  18. Marco September 30, 2012 at 3:24 am #

    I rode bi-articulated bus (both diesel and electric) in Geneva, and they seem to turn quite easilz even in narrow roads with sharp turns!

  19. Nathanael October 4, 2012 at 5:41 pm #

    There are permanent and unavoidable disadvantages to really long buses, the biggest of which is fishtailing.
    There’s a reason that the longest trucks/lorries have only three trailers after the tractor, and they don’t even have people riding in the trailers.
    The only way to fix this is to put the bus on tracks, and at that point you have a train and you might as well use steel wheels and steel rails.
    In contrast, trains can be really arbitrarily long (300 cars is not unheard of for freight trains).

  20. Nathanael October 4, 2012 at 5:43 pm #

    “The bus prototype is built with multiple steerable axles. The wheels follow one another around a curved virtual track.”
    So, it’s a train, but ten times more expensive to build than steel wheel – steel rail – passive stabilization technology.
    This is what ALWAYS happens with “buses are the future!” claims — they reinvent the train, only more expensive and less reliable. Sigh.

  21. Nathanael October 4, 2012 at 5:45 pm #

    Judging by what happens with trucks (lorries), bi-articulated buses are pretty much the limit for bus length. Tri-articulated simply won’t work unless you effectively put them on rails.

  22. Dennis Hindman October 25, 2012 at 11:51 pm #

    Two advantages that rail has over buses that are often overlooked is modularity and being able to drive it from either end (no need to turn the vehicle around). Train cars can be added for peak hour demand and subtracted on off peak hours. This Fraunhofer Institute idea for a modular bus incorporates the ability to detach a section and also drive the articulated bus from either end.
    This reduces operational cost by converting the buses to a shorter length during off-peak hours. It would also allow a transit agency to buy one bus model that could be used articulated or un-articulated. This Increases its flexibility by being able to use it on any route and reduces the need for stocking multiple parts for different bus models.

  23. Daniel April 5, 2013 at 10:09 pm #

    These are actually popping up increasingly often, I know of at least four Swiss cities where they are in regular service. As others have pointed out, their maneuverability is very appropriate. Usually there are no adjustments necessary for even seemingly tight city street corners. They’re a sight to get used to at first, but experience seems to show no noteworthy problems with city streets or traffic. They don’t usually run on separate lanes, and don’t need to.
    Niche vehicles are costly, yes, but at the rate that they are being put into service, I don’t think they can even be considered a niche product anymore. I’d assume they’re giving comparable tram or train vehicles a run for their money in terms of building and maintenance cost.
    One other advantage of a bus over trams that no one seems to have mentioned is that they, obviously, don’t run on rails. The transport company can divert them, and offer special service for bigger events at locations where there is no regular service.
    In my hometown of Lucerne, we haven’t had a tram service for more than 50 years. It was shut down in favour of bus service, mainly due to increasing dissatisfaction of the population regarding space the stops took away from roads and pavements. We had a vote on it in the 50s, and the citizens chose to get rid of the tram lines. Considering the immense initial investment, years of construction in a congested city centre, and yes, how well changes such as introducing bi-articulated buses have allowed us to cope with changing requirements so far, people just don’t see a return to rail-based transport within the city having any real payoff. Plans in that direction have repeatedly been smashed by the public. People aren’t bothered by bi-articulated buses, but there is very little interest for rail-based inner-city solutions around these parts, from both the population and the transport companies.

  24. Mrs.Santos August 6, 2014 at 9:19 am #

    I’m doing a thesis about this kind of transportation thing.

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