In article , David Bradley
writes
In fact in Rome where
a new trolleybus systen has been introduced, part of the route has no overhead
wiring because of a desire to have a clutter free skyline in an area of
particular historical importance. The booms can be disconnected and
reconnected to the wires without the need for the driver [or crew] to leave
the vehicle. Clearly this ability can also be used in the first point that
you made. I don't see too much difficulty in flicking a switch to lower or
raise the booms as required, thus enabling that fabled overtaking of service
vehicles,

The only places where I've seen this de-wiring and re-wiring
arrangement, the re-wiring can only be done at specific locations -
there's a sort of plastic M attached to the wires that guides the booms
into place. This is fine for the sort of situation you describe in Rome,
but it does *not* work for unplanned overtaking.

--
Clive D.W. Feather | Home:
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