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(/) Pacific Stations In the Pacific tlie major developments have been the commissioning of the new combined administration and aeradio communications stations at Rarotonga and the commissioning of the new high-frequency direction-finding station at Nadi. Much rebuilding and consolidation work is still required in the Pacific, and preliminary plans for this programme have been prepared. (g) Meteorological Radar The Branch has accepted the responsibility for the engineering and maintenance of the radio and radar equipment used for meteorological observations. It has installed a high-powered radar unit at Nadi, and the engineering of the Invercargill installation in conjunction with the new aeradio station there has reached a stage where construction work can start as soon as a contractor can be found to carry out the work. The fourth and last of the sets produced by the Dominion Physical Laboratory is available for installation, and four war surplus 10 cm. 200 kW. anti-aircraft gun-laying sets have been purchased from the United Kingdom. The Meteorological Office will use the radar equipment to follow the flight of special balloons, obtaining both their plan positions and heights. They will thus obtain information on the wind velocities at various heights to enable them to provide more accurate forecasts of the conditions to be expected by aircraft. The new jet-propelled aircraft that maybe expected to operate on the international routes in the near future will fly at heights greater than 20,000 ft., and information on the air turbulence and wind speeds at these heights is urgently needed. (h) Research and Development In view of its interest to this Branch, close liaison has been maintained with the progress of the investigation being carried out by the Department of Scientific and Industrial Research in the procurement of the basic propagation characteristics of New Zealand's soils, particularly at medium and low frequencies. This work was sponsored by the Radio Research Board at the instigation of this Branch. With a long-term view towards planning the technical facilities required for the solution of the difficulties of Air Traffic Control at the new Rongotai Airport, practical analysis has been made of overseas mathematical data associated with the general problem of the control of traffic at busy airports. Original work of fundamental value has also been carried out, in conjunction with the Department of Scientific and Industrial Research, in the mathematical analysis of existing traffic in the Cook Strait. Theoretical coverage and propagation calculations and graphs have been made for the introduction of very-high-frequency techniques for all air-to-ground communication. The introduction of very-high-frequency techniques for air-to-ground communication on the airways is an urgent operational requirement which is long overdue. Now that _ the preparatory theoretical work has been carried out, the newly recruited technical staff should be able to proceed with the practical development of this scheme, and it is hoped to take effective strides towards its innovation during the coming year. (i) Staff General comments have been made above regarding the shortage of staff. An intensive recruiting drive was made during the year which yielded a fair response for technical staff, but there is almost a complete absence of professional engineers with the proper training and experience in radio and telecommunications, and it has therefore been necessary to initiate recruitment overseas to obtain professional staff of the required calibre.

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