ntt@dciem.UUCP (Mark Brader) (07/18/84)
On Sunday I took one of the preview rides on the Scarborough RT line. Since then I've been failing to remember to bring along the brochures they handed out, but never mind, I will write this up from memory. This system has characteristics of both light and heavy rail transit and the working name before they settled on RT was ICTS - Intermediate Capacity Transit System. The tracks are on their own right-of-way, mostly on the surface beside a railway, plus some elevated route and a short tunnel section. The stations are spaced like subway stations and have high platforms. The trains are capable of running at 50 mph but service speed will be 43. The conversion from the originally planned line, running with streetcars but designed for eventual upgrade to subway, to ICTS, was supposed to cause a year and a half's delay in the opening, and the now-planned date is next spring, a further half year behind. As I said, there was politics here. The motors are *linear induction*; that is, coils fixed to the bottoms of the bogies (trucks) react with a flat, foot-wide aluminum strip set in the center of the track, called the "reaction rail". This, combined with welded track, makes for a very smooth and quite quiet ride. And the only moving part in the motor is the train itself, which should help with maintenance - but it also means that track maintenance is more critical. The motor can be used for braking, either regeneratively or by reversing; this is supplemented by disk brakes and in an emergency by track brakes. The power supply is 600 volts DC, same as the TTC's subways, streetcars, and trolleybuses. But it is delivered by *third and fourth rails* - no return current through the track. The live rails appear to be aluminum and they use the side-contact system...one is set a couple of inches above the other on the same side of the track. Above them is a protective cover which appears to be aluminum also. (The TTC subway uses a conventional top-contact third rail with return current through the track, and a wooden protective cover over it. Using an insulator for the cover seems more sensible to me.) So we have tracks consisting of, from top left to bottom right, a protective cover, two power rails, one running rail, one reaction rail, and the other running rail. (Running rails are set at standard gauge). But even that is not all... About four inches to each side of the reaction rail we see a black cable maybe a centimeter in diameter. These form a series of loops which are used for communication between the train and the computer controlling it. I was informed that the driver has to do nothing at all; I asked, "Not even push a go-button at stations?", and the reply was, "I don't think he has to." (Other automated systems such as London's Victoria line and BART have retained this requirement, I understand.) Manual control is also possible, of course. As on some other computerized lines, there are no visible signals, and the trains do not accelerate directly from zero to full speed, but go by stages, which I find slightly annoying. The other rare feature of the system is that the *axles* of the cars are individually steerable, which enables them to take tight curves smoothly. Accordingly, the route includes at least one tight curve. The cars are about the size of buses, with two sets of sliding doors on each side. They seat 30 and are supposed to have standing room for 80 at a crush. Each car has a cab at one end and they will run in coupled pairs, which in turn can form trains of up to 6 cars in total, giving about the equivalent of half a subway in crush carrying capacity. There is equipment under the seats, so the seating plan is fixed. Passenger emergency alarms are fitted, much as on the TTC subway cars. The car bodies are aluminum and fiberglass. I thought they ran very nicely in the preview (which continues each Saturday and Sunday until August 14, 10 am - 4 pm). I do not care to predict how well they will stand up in regular service, though. Mark Brader