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Capacity of PAT guideways 

Conclusion

The maximum number of PAT vehicles per hour for a single guideway:

 Maximum vehicles per hourSpeed for maximum throughput
No headway1400; -used in models2 m/sec, 7.2 km/hr
0.2 g emergency deceleration14504.5 m/sec, 16.1 km/hr
0.5 g emergency deceleration22507.1 m/sec, 25.5 km/hr

In the grand scheme of things this seems rather small.

Real figures to put this in context

Estimated for 10 rail lines to East London Olympic Park stations320,000
London Crossrail: projected 24 trains p hr78000
Wembly Park Station can now accommodate...37500
National Rail into Charing Cross London33000
Bus lane in New York31000
Cabins on a conveyer belt, 1.2 passengers/cab, 40 km/hr 20000
10 section articulated vehicle (SSAV), 40 passengers, 120 km/hr 17000
20 Eurostar trains per hr, all 800 seats filled16000
Average air travel, UK to Europe7000
Max cars (2800/hr) on one lane of motorway, 1.2 passengers/car2800
Max PAT, 0.5g emergency breaking, 1.2 passengers/cab, 20 km/hr2600
Max PAT, 0.2g emergency breaking, 1.2 passengers/cab, 20 km/hr1700
One person every 3 seconds through turn-style1200
Taxi 2000, case study for Albuquerque, 2006. 702 Cabs/hr, 1.2 passengers/cab847

Ultimate limits of PAT guideways

The ultimate capacity of the guideway feeding the station is set by minimum headway considerations. The figure shows the capacity of a guideway, limited by the "brick wall" criterion, depends on speed and maximum emergency deceleration. The lower value of deceleration of 0·2 g is the estimated maximum breaking effort that can be reliably achieved with rubber tyres on concrete for any weather condition. The higher level is probably the limit for not injuring passengers too much in what is expected to be a rare fault condition.

 

The yellow line represents the speed of the vehicles in the models, set at 2m/s, which is sufficiently low that headway can be neglected. (Note that this is about the same speed as fairground bumper-cars or Dodgems.) The maximum capacity of a station with this speed, vehicles at 5m intervals and ignoring headway limits, is indicated by the blue cross.

Note that the station here is defined as a number of berths at which passengers board and alight. These will be connected by a network of branched tracks with an upper speed limit of around 2m/s to a single entrance and a single exit. These will link to the network via deceleration/acceleration sections.

 Higher guideway capacity can be obtained by more effective breaking. As shown by the upper curve, a 0·5 g breaking effort allows a capacity comfortably greater than station capacity.

It can be seen that there is an optimum speed for which the capacity of the guideway is maximum. For the lower maximum deceleration, the maximum capacity is about equal to the station capacity. If the guideway is operated at a design speed of, say, 40 km/hr, then the station capacity is limited by the guideway.

Even greater capacity can be obtained if the vehicles can move in platoons:

Maximum traffic vs platoon length