What is the Best Forn of Urban Transport
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Merits of Motorbuses, Trolleybuses, Trams and Underground Railways Compared
THE subject introduced by Mr. it. .Courson, Chef du Service Cornmercial de la Regie Autonome des Transports Parisiens, was "The Relationship of Buses, Trolleybuses, Tramcars and Underground Railways in Urban Transport."
The author asked if we could look upon the problem of passenger transport in cities as having been solved. He wondered whether it would even continue to be set. The amazing development of the car may lead us to think that private transport may eventually supersede public conveyance. Even if the cost of running a car could place it within the reach of the great majority, however, the problems of traffic control and parking would, in cities, remain to be solved. Short of gigantic public works, no solution to them can be visualized.
-Road traffic increases more rapidly than streets are Widened and various transport media tend to offer equal comfort for about equal expenditure,
hence the choice of the solution is E the more critical.
The author considered the . vario forms of public service urban transpe from the angle of:—(a) The extent which they can Cope with traf requirements 4capaeity, passenger flo. transport potentiality).
(b) Advantages and disadvantages f the user and operator.
(c) Cost,
Dealing. with (a), capacity is ii number of fares (seated and standin that can be taken by each unit (sing vehicle, vehicle plus trailer, trait Maximum capacity may depend 4 several factors: legislation limitii
dimensions, structural possibiliti restricted only by maximum axle loa method of collecting fares (if this on board) and standard of comfo The capacity for a given size of vehic actually depends on the ratio of ser to standing room.
The following figures indica average normal capacity:— • Taxi 4, coach 25 to 30, bui or irolle bus 50-65, tram 100, train plus trail 200, Paris Metro (five carriages) 7C underground railway (six carriage 1,500, New York Subway 2,700.
Assumed minimum intervals, subte to corrections for particular cities, at a seconds:---Taxi 5, bus or trolleybus 0, tram 30, tram plus trailer 35, Paris 4etro 90, standard-gauge underground ailway 120.
With these figures the passages per our and the corresponding passenger low respectively are: Taxi 720, 2,880; ouch 180, 4,500; bus or trolleybus 180, 0,800; train 120, 12,000; tram plus railer 100, 20,000; Paris Metro 40, .8,000: underground railway 10, 45,000.
The influence of idle periods spent in urn-round is impOrtant, especially Luring rush hours. Each increase in ialts at both termini which equals the espective interval requires an addiional transport unit. Maximum speed, irovided it he not too low, affects Ommercial speed only slightly. Frement stops limit the maximum to 25 to m.p.h. From the economic point of icy./ alone powerful acceleration may ie. worthwhile,
Higher Speed Costs Little
Tests with a European 110 h.p. bus tad an American 170 h.p. bus have hown that the latter can add 5 per ent._ to the commercial speed with 25 ler cent, increased fuel consumption. ks the oil fuel accounts for about 10 ier cent, of total expenditure the latter s, therefore, increased by 2.5 per cent. iowever, wages and other costs are educed by 5 per cent, the total, thereore, remaining practically the same :nd passengers receive better service.
With regard to braking, there are atisfactory solutions for all forms of ransport. The best hill climber is mdoubtedly the trolleybus.
Summing up, the author estimated he transport potentiality in maximum ealues as follows, the first figure being he speed in kiloms. per hour and the ,econd the number of passengers:—
Taxi 25. 72,000; coach 20, 90,000: aus 18. 194,000; trolleybus 20, 216,000; ram 20, 240,000; tram plus trailer 18, 160.000: Paris Metro 22, 616,000; inderground railway 28, 1,260,000.
iome Interesting Comparisons
Dealing with advantages and distdvantages of the various forms of ransport as they concern the user, the author said on the safety aspect, that iehicles on tyres, in spite of their freeloin and availability to skirt obstacles, tre subject to road and weather coalitions thus being more liable to tccidents.
As regards regularity of service, areakdowns are more serious with /aides on rails' for they paralyse !ntire lines. Traffic congestion, ternaorary blocks due to public works, arocessions, etc., may stop trams and wen trolleybuses, Motorbuses alone, 3eing independent, can alter their routes.
On the matter of comfort, there is general progress, but in smoothness in starting, the bus, with automatic gearbox and hydraulic clutch or torque zonverter, is almost as satisfactory as electrical vehicles with their multinotch equipment.
Next the author dealt with the advantages and disadvantages of the various means as they affect the operator. The economical desirability of reasonably high speed had been pointed out, but operators also desire to -compete effectively with private transport and taxis, and not slow down road traffic.
The freedom of movement of buses, allowing overtaking, may usefully he turned to account, particularly on radiating suburban routes. During rush hours, traffic on these may be much heavier in one direction than in the other and may increase continually from the suburban to the urban terminus. A service by zones may be envisaged. Vehicles servicing distant zones making non-stop runs in those nearer the centre, thus improving their rotating velocity.
In smaller cities it may be advantageous to operate buses taking no more than 30-40 fares. It is important, where traffic is slight, to bring in the factor of minimum acceptable interval. Prolonged waiting may make people walk. Also custom should be built up by small vehicles running frequently. The complete independence of the bus may lead to its being preferred, particularly where routes pass through expanding districts where traffic has not become stabilized.
In view of the expense of their fixed equipment, trolleybuses seem to be worthy of consideration only above a certain load. This expense must be spread over a large number of passengers, but they easily compete with motorbuses on hilly routes.
The general oufline of urban transport in a large city may be as follows:— A basic system of railway or trams for rush-hour mass transport, a complementary bus or trolleybus system in the central zone to give the necessary connections, for suburban routes lines leading to the basic system, with trams for heavy traffic routes and trolleybuses or motorbuses elsewhere. Bus services should also be employed for outer service lines.