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being maintained by the Civil Aviation Branch. The siting and detailed planning of the radio beacons to be installed at Ohura and Pahiatua has been completed, and these beacons should also be in operation in the near future. Radio Ranges The Ministry of Works has repaired the breakwater around the Wellington (Porirua) radio range site, and the site has thus been stabilized. A series of flight checks and ground checks has shown the courses to be stable. However, multiple splits exist on the portion of the south leg south of Rongotai and on the west leg of the range over the Marlborough Sounds. This trouble is not entirely due to the site chosen, but is due to the geographical configuration of the area to be served by the installation. It is probable that the trouble can be reduced by swinging the range legs on to new courses, and preliminary trials with new courses have already been carried out. The radio range has been in use as a radio beacon since Ist June, 1948. In order to provide navigational assistance on the proposed new air route Auckland-Ohura-Wellington, the south leg of the Whenuapai Radio Range has been experimentally swung on to that direction, and operational trials are being made of the new alignment. If the trials prove successful, the new alignment will be retained and the fan-marker now sited at Mangere will be replaced by a fan-marker on the new course. A new site has already been selected in the Titirangi area, and work is progressing on the planning of the new fan-marker. Direction Finding Stations The medium-frequency direction-finding stations were closed down on the 20th December, 1948, simultaneously with the change-over of the communications channels to high-frequency. On the 30th September, 1948, the high-frequency direction-finding station at Waiuku was opened to take the place of the station at Musick Point operated on behalf of the Civil Aviation Branch by the Post and Telegraph Department. A new highfrequency direction-finding station has been installed at Nadi and will be brought into service after flight-checking. Co-operation With Australia In May, 1948, the Senior Radio Engineer of the branch visited Australia in order to obtain information regarding 200 megacycles per second radar (Distance Measuring Equipment) (D.M.E.) and to arrange for the experimental installation of such equipment in New Zealand. The opportunity was taken to observe the progress in the development of radio navigational aids by the Australian Council of Scientific and Industrial Research, and in the application and operation of radio navigational aids by the Australian Department of Civil Aviation, and to study the organization of the Australian Airways Engineering Section. The radio manufacturing potential in Australia was also investigated from the aeronautical point of view. Research In order to provide more exact engineering and operational performance information regarding low-frequency radio beacons, the Inter-departmental Radio Research Board has, at the request of the Civil Aviation Branch, agreed to support a programme of research into the fundamental radio propagation characteristics throughout New Zealand in respect of these frequencies. These characteristics have never been previously investigated at frequencies below the broadcast or medium-frequency band.

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