§ Mr. Kershawasked the Secretary of State for the Environment to what extent the cost of the Road Information Transmitted Aurally (RITA) depends upon the speed of the vehicle receiving the signal; upon what speed the timing of the signal is based; and what is the cost per mile of the three possible transmitters, namely, wire loops in the road surface, cables, or single roadside transmitters, mentioned by the Minister in the Official Report, column 881, of 26th June 1975.
§ Mr. CarmichaelVehicle speed affects the design of transmission aerials—loops or coaxial cables—and governs the length of message zones. Present thinking allows for zones 1 km. and ¾ km. long in rural and urban areas respectively, which should enable drivers of vehicles travelling at speeds up to 70 m.p.h. to receive at least two complete 10–second messages. Since the use of roadside transmitters is unlikely, costs for these have not been closely investigated. Costs for wire loops and coaxial cables are each estimated to range from £6–8,000 per site. It would suffice if these sites were placed 3 km. and 1 km. apart in rural and urban areas552W respectively, in which case the average cost of adding the road element of RITA to the present matrix system would be about £5,000 motorway mile.
§ Mr. Kershawasked the Secretary of State for the Environment what costs will be entailed in suppressing interference with radio signals caused by operation of the "Aware" system, especially in heavy commercial vehicles; what it will cost to provide a dimmer on the panel so that the signals may be seen both by night and by day; and what steps he intends to take to prevent interference from and with local radio sets.
§ Mr. CarmichaelThe design of AWARE effectively guards against interference from outside, and Home Office regulations prescribe that a frequency allocation would be made, to avoid interference between AWARE and other radio transmissions. Brightness in the panel is controlled through a simple automatic device in the car. It is not practicable to identify the cost of either of these two features of AWARE's design.
§ Mr. Kershawasked the Secretary of State for the Environment, in view of the fact that each separate carriageway signalling point for the traffic control system Advanced Warning Equipment (Aware) will cost £60,000 and that cost and installation charges in a vehicle will be between £40 and £50, how many will be required per mile of road.
§ Mr. CarmichaelTransmitters for AWARE could probably best be located at about the same intervals as the present matrix signals. On this assumption, each separate carriageway signalling point, and each dual site serving two carriageways, is estimated to £3,000 and £5,500 respectively to the costs of the present matrix system. Optimum distances between sites are still under investigation, but a likely order is about 3km. in most rural areas, and between ½ and 1 km. on roads with heavy traffic. The cost of receivers, installed in vehicles, is expected to be about £15–£20 each.