[said Larry] > > [log in to unmask] wrote: > > >This is of interest for Amtrak fans - the new "Acela Express" trains > >have TGV-based locomotives, but traditional separately-coupled > >coaches of Canadian design. Current Amtrak plan is to start operating > >these trains (at 150 mph max) in November between Boston and Washington. > > Speaking as someone who lives at the opposite end of that run from Mike, > I would like to point out that in 1999 this service was also supposed to > start in November (and several months in between). In November 2001 I > do have to go to Washington, so maybe by then... > Yeah, Amtrak is having some teething problems with the new trains. I think they are serious about the November startup, though - see http://www.amtrak.com/news/archive/atk00125.html Delays like this are very common with this kind of new RR technology - happens in Europe all the time. In the US it is so rare to introduce new RR technology that we tend to overreact to break-in problems. We also live in very impatient and politically poisonous times that any glitch in anything Uncle Sam touches is cause for terrible invective. AFAIK the teething problems have not been software-related, but more with mechanical type things like wheel and brake wear. From the safety-critical point of view, though, they did have one really interesting computer+mechanical design flaw. The coaches are about 4" (~10 cm) too wide. Normally this would not be a problem, but these trains have an active-tilt mechanism for going faster around curves. GIven the fixed distance between the 2 tracks in opposite directions, one must do a worst-case analysis to be sure the whole system is safe. The on-board computers control the tilt mechanism. Suppose that, in a worst-case scenario, on a certain curve the train on the _inside_ track is tilted (erroneously) toward the _outside_ track (instead of toward the center of the curve). And suppose a train is going by, simultaneously, on the outside track and tilts properly. In this unlikely, but theoretically possible, scenario, the trains would not touch IF they were the right width. But because of the 4" extra width, they could collide. As I recall, this analysis was based on theory and simulation. This analysis caused a HUGE flap between Amtrak and the contractor. Needless to say, each blamed the other and the situation remained fuzzy. In the end, it was decided to simply adjust the mechanism so the trains tilt a bit less. But this will also slow them down a bit, which is why the NY-Boston timings will be just a few minutes slower. From what I read, once the trains are running regularly they'll have empirical data on the basis of which they can decide whether to notch up the speed. My big problem with the new service is the _price_. It looks like they are setting it quite high to test what the market will bear. They can always lower it later, I guess. Mike