Omega Report Tabled EXCLUSIVE USE IN WAR TIME DOUBTED

Press, Volume CVIII, Issue 31753, 9 August 1968, Page 1

Omega Report Tabled EXCLUSIVE USE IN WAR TIME DOUBTED

It was estimated that Omega signals could be received and used by submarines operating with submerged aerials, down to 40 feet at least, but probably not more than 100 feet, saidareportof a special committee of the Royal Society of New Zealand tabled in Parliament yesterday.

The committee said it was theoretically possible and probably practical in a submarine with on-line computers to correct for wave motion and depth, and use the Omega navigation system with a submerged aerial without significant loss of accuracy as compared with use above the sea surface.

The committee said it had insufficient information on all possible measures and counter - measures to say that the system could be used by the United States and allies exclusively in time of war; but it believed the system was susceptible to jamming and doubted if it would be rea’ly useful exclusively to one side in war time.

An Omega station in New Zealand would be of no use to internal airlines or coastal shipping, and would cause serious interference to New Zealand’s very low frequency research programme, said the report The committee consisted of a fellow of the society. Dr M. C. Probine, as chairman, with the following members of the society’s national committee for radion science: Professor R. L. Dowden, of Dunedin, Dr H. A. Whale, of Auckland, Dr G. A. M. King, of Christchurch, and Messrs G. McK. Allcock and G. Burtt of Wellington. The committee’s summary said that the Omega system was in an advanced state of development, and was expected to give world-wide coverage using only eight transmitting stations. It was proposed that ii would become fully operational in 1975. “A good, long-range navigation system should be useful to New Zealand because of its isolation, its long sea and air routes, and its widespread

national interests from Antarctica to its island territories near the Equator,” the report said. “The system is independent of weather conditions and is relatively independent of ionospheric disturbances.” Simple receiving equipment could be relatively cheap—about U.S. 32000 —but fully automatic "nd more accurate equipment could be much more expensive, the committee said. Catalogues of commercially available American equipment had prices up to S3O,COC and in one publication prices up to $65,000 were mentioned. British companies were interested in making Omega receivers, and the committee understood that British commercial interests took the view that there was need for only one global VLF navigation system and were refraining from further development on othei systems until the Omega system had been thoroughly tested. Several air and shipping lines from a number of countries were interested in or actually making trials uf the system. Antarctic Use There seemed to be no reason why the Omega system should not be a useful navigation aid in the Antarctic if it was remembered that appreciable loss of range to some of the beacons would occur if the path was over a significant amount of the ice-cap. The United States Navy had said that when the system became fully operational, central control and operation of stations under United States control wo ’d be

handed over to the Coast Guard. “As far as we are aware, i it has not been proposed that i the system should eventually i be operated by an intema- i tional agency such as some i branch of the United Na- < tions,” the committee con- i tinued. “This may well be < desirable. On the other hand. 1 it may be that no such agency as at present constituted has the resources to enable it to ( carry out the required con- ( trol of time and frequency.” j WITHIN 600 MILES < Omega signals from a par- 1 ticular station were subject < to gross errors if used within i about 600 miles of the station, the committee said I Thus, the establishment of a < station in New Zealand would 1 not be- of direct benefit to i coastal shipping or internal 1 airlines. The needs .of those 1 interests could better be > served by siting the station t so it was at least 600 miles < away from New Zealand. 1 New Zealand had an inter- 1 national reputation in radio < research in the VLF band I used by the Omega system. ’ The country was ideally situ- s ated for studies of very long 1 distance propagation of VLF I transmissions from Europe 1

and North America. Work in New Zealand had contributed vitally to the total research data that proved that a worldwide VLF navigation system such as Omega was feasible. Transmission from a local station would be useful for studying the propagation of VLF radio waves over relatively short paths under the ionosphere. In the long term, such studies could assist in solving some of the outstanding problems of high frequency radio communication associated with anomalous effects in winter, which might be of meteorological origin. INTERFERENCE A disadvantage was that an Omega transmitter could cause serious interference to broad band VLF radio receivers used in the study of VLF propagation and natural emission in the magnetosphere. “If an Omega station is not to produce serious interference it must be sited several hundred miles from the VLF receiving sites in Otago and Wellington, preferably not in New Zealand at all, although interference from an Omega station at say North Cape or the Chatham Islands may not be too serious,” the committee concluded. “At this distance the research advantages of an Omega station would still apply. An Omega station in the South Island, however, may make some important aspects of present VLF research impossible.