Post by Deleted on Apr 8, 2007 22:01:01 GMT
pacific said:
Another thing I thought about emergency brake rates - is there a physical limitation?There's always talk about wheel lockups/flatspotting in rain on the Central Line under ATO so maybe, increasing the deceleration rate is actually not feasible due to physics itself.
Trams (with magnetic track brakes), LIM trains (again with magnetic track brakes) and rubber tyred metro trains can have emergency braking rates of 3-4ms2. The latter two have their emergency braking rates clipped in public service so as to not injure passengers. As trams are sometimes road running they have to have the option of fast braking rates.
From data I've seen published, some conventional metro trains could brake at around 1.8ms2, but are limited to 1.3-1.4ms for safety reasons.
So I don't think physics is usually the reason for the braking rates, it's passenger comfort.
