26. Dr. Bennettasked the Minister of Aviation whether he is aware of the breakdown of air traffic control at Idle-wild on 21st May last, with delays or immobilisations of British aircraft for an hour or more; and if he will draw the attention of the International Civil Aviation Organisation to this consequence of their adherence to the VOR-DMET system as against a British hyperbolic system of navigation which would safely provide a much higher frequency of take-off and landing.
§ The Parliamentary Secretary to the Ministry of Aviation (Mr. Geoffrey Rippon)The only delay of which I am aware occurred on 20th May. In this case the Boeing 707 aircraft of B.O.A.C. was No. 24 in the take-off queue at Idle-wild and suffered a delay of 1 hour and 7 minutes. I do not think any conclusions can be drawn from this incident on the merits of the VOR-DMET system.
Dr. BennettIs it not a fact that on this occasion—on the date of which I stand corrected—the delay to aircraft was such that by the time an aircraft got to the front of the queue it might 22 have had to go back to refuel? Was that not a direct consequence of inadequate traffic control facilities, which are lacking there but which we have in this country? Will not my hon. Friend advocate the introduction of a far more sophisticated system? Does not the opinion of international airline pilots support that view?
§ Mr. RipponAs I said, I do not think that any conclusions can be drawn from this incident about the merits of the two systems of navigation, but we believe that in areas of dense traffic something more advanced than the VOR-DMET system will be needed. It is also true that the international pilots' organisation favours an area coverage system with pictorial presentation.
31. Dr. Bennettasked the Minister of Aviation what are the comparable costs to the Exchequer of the installation, and the maintenance, of a VOR and DME beacon system in this country, and of a hyperbolic area-coverage navigation system.
§ Mr. RipponIt is not yet possible to estimate the cost to the Exchequer of the VOR/DMET stations that will be required as a result of the recent decision of the International Civil Aviation Organisation. The Decca hyperbolic area coverage system is already being commercially operated in this country and reliance upon this system would naturally involve little additional outlay.
Dr. BennettCould my hon. Friend give the House some idea of which would be the cheaper system to operate?
§ Mr. RipponToo direct a comparison of cost is difficult because one has to have regard to the extent to which the existing systems are already developed. As I have said, we believe that in an area of high traffic density the Decca system is not only more efficient but cheaper.