starrymarkb
Established Member
Would the VAL style of metro system be suited to any UK cities?
Think he's on about this...
http://en.wikipedia.org/wiki/Véhicule_Automatique_Léger
Personally I wouldn't like a raised railway anytime soon, I find them a bit ugly.
wikipedia said:Advantages of rubber-tyred metro systems (compared to steel wheel on steel rail):
- Smoother rides (with little jostling around)
- Faster acceleration[1]
- Shorter braking distances, allowing trains to be signalled closer together
- The ability to climb or descend steeper slopes (~gradient 13%) than would be feasible with conventional rail tracks so gradient conventional rail tracks would likely need a rack.
- Quieter rides in open air (both inside and outside the train)
The higher friction and increased rolling resistance cause disadvantages (compared to steel wheel on steel rail):
- Higher energy consumption
- Possibility of tyre blow-outs - not possible in railway wheels.
- More heat generated
- Weather variance. (Applicable only to above-ground installations)
- Losing the traction-advantage in inclement weather (snow and ice)[2]
- Heavier as steel rails remain for switching purposes to provide electricity to the trains and as a safety backup[3]
- Tyre replacement cost[4]
[edit] Notes
^1 Modern steel-on-steel rolling stock using distributed-traction with a high-proportion of powered axles narrowed the gap to the acceleration/performance found in rubber-tyre rolling stock.
^2 To reduce weather disruption, the Montreal Metro runs completely underground. On Paris Métro Line 6, upgrades of tyres (as used with cars) and special ribbed tracks have been tried out.
^ 3In effect, there are two systems running in parallel so it is more expensive to build, install and maintain.
^4 Rubber tyres have higher wear rates and, therefore ,need more frequent replacement. Although steel wheels set is more expensive than tyres, the frequency of their respective replacements makes rubber tyres the more expensive option. Rubber tyres for guidance are needed.
I was refering to the concept of the automatic light metro 
Any such decision is a compromise for circumstancesI was refering to the concept of the automatic light metro
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In France the main home of rubber tyred trams is also the home of Michelin, coincidence?
In France the main home of rubber tyred trams is also the home of Michelin, coincidence?