§ 58. Mr. Onslowasked the Postmaster-General what estimate he has formed of the probability that, if the planning of microwave communications systems within the United Kingdom is based on the assumption that the radio radius of the earth equals its true radius, the performance of such systems will be impaired by unfavourable propagation conditions for more than a total of 60 seconds in any two year period.
§ Mr. MasonThe performance of such systems would be impaired by unfavourable propagation conditions for about 5 per cent. of the time. This is why we do not base the planning of our microwave communications system on this assumption.