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The reconditioning of equipment obtained as war surplus has continued. With the growth of the organization it has been found necessary to acquire dispersed stores buildings, but this has not provided adequate space for the efficient functioning of the central maintenance and repair depot, and an urgent requirement exists for still more space. Considerable difficulty has been experienced in obtaining, issuing, and bringing up to date the necessary technical publications to support the wide distribution of the varied war surplus equipment, but generally speaking the field organization is now effectively supported by the necessary technical instructions and literature. (c) Medium-frequency Radio Beacons Two new medium-frequency beacons have been erected as permanent installations, one at Pahiatua, the other at Ohura. The Pahiatua beacon will improve navigational facilities for flying over the Manawatu Gorge, and Ohura for flying through the centre of the North Island. A temporary installation has also been erected at Waitaki. Considerable difficulty was experienced with the Ohura installation. It was at first difficult to find a compromise between conflicting operational and technical requirements, but when this had been done it was found that bearings of the quality obtained were useless for flying, due, probably, to disturbances caused through reflection of signals by the mountains and to unknown variations in earth conductivity. Unfortunately no basic information is available as to propagation characteristics over most of New Zealand, and is particularly lacking in such remote areas as the Kingcountry. Experience has shown that the geology of New Zealand presents unusually difficult problems to the radio engineer. The Ohura beacon is now giving satisfactory service during hours of daylight using a frequency in the " high frequency " band. (d) Radio Ranges The northern leg of the Wellington (Porirua) radio range was declared operational on 14th June, 1949. This leg provides track guidance on that part of the trunk air route between Wellington and Wanganui. Alignment and flight checks of the western leg, directed over the Marlborough Sounds, are to be undertaken shortly, and it is anticipated that this leg will be brought into operation at an early date. This leg will be used by the trans-Tasman flying-boats using the Wellington terminal. Realignment of the Whenuapai (Auckland) and New Plymouth radio ranges to provide navigational assistance over the new air route Auckland-Ohura-Wellington was carried out, and a fan marker on the new alignment of the southern leg of the Whenuapai range was installed in the Titirangi area. A similar installation has been commenced at Muriwai on the western leg of that range which, when commissioned, will considerably facilitate the approaches of the Tasman flying-boats to the Auckland Harbour. (e) Direction-finding Stations The installation of a high-frequency direction-finding station afrNadi was completed and the facility brought into operation on the 15th July, 1949. In conjunction with Tasman Empire Airways, Ltd., and New Zealand National Airways Corporation, tests were recently carried out on the degree of accuracy of bearings obtained from stations in the South Pacific area. The results obtained are now being analysed to ascertain the degree of reliability obtainable from the stations by aircraft flying over various sections of the South Pacific air routes.

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