wjm@whuxl.UUCP (MITCHELL) (07/16/84)
<gulp?>
Personally, I would class BART as a heavy rail system, since it has all the
characteristics of heavy rail, including
1) High platform operation only (no provision for street level loading)
2) Third rail power supply (a sufficient although not necessary condition -
some heavy rail systems use trolley wire or catenary power , e.g.
Boston's BLUE Line from Maverick to Wonderland)
3) Totally separated right-of-way (a necessary although not sufficient condition)
Actually, I believe the terms heavy and light rail, refer to the weight of the
RAIL used in the system, rather than the weight of the cars, since the classic
heavy rail systems (eg. NYC) use rail that is as heavy as mainline railroad rail
(132 lb/yard) while light rail systems (back when they were called streetcars)
use much lighter rail (on the order of 60lb/yard).
Regards,
Bill Mitchell (whuxl!wjm)