Bringing Vessels Safely Past N.Z.'s Rock-Bound Coastline

Radio Record, Volume VIII, Issue 29, 25 January 1935, Page 14

Bringing Vessels Safely Past N.Z.'s Rock-Bound Coastline

Radio Beacons Aid Mariners During Fog

a ship to keep afloat; fifty miles from the nearest sound signal through a thick, grey pall. ... Even as little as ten years ago this would mean "dead slow" until the fog lifted. To-day it can mean only the slightest delay,"if any, in those parts of the world where radio beacons have been provided. Now New Zealand is following the latest in navigation aids, and within the next year it is expected that the, proposed radio beacon at Baring Head, outsid2 Wellington, will be operating. ‘At present there is only one radio beacon in New Zealand, that at Cape Maria. As experiments are made and improvements are perfected, the Dominion’s coastline will become as completely provided with beacon stations as the irregular nature of the coastline on the main shipping routes may watrant. Masters of overseas vessels have for years remarked upon the inadequacy of the existing charts of New Zealand’s coast, and the rocky traps into which occasional. big ships have fallen prove a reason behind these com-. plaints. Outside of the individual harbour limits the charts for many parts of the coast are admitted to be out of date-a dangerous factor in navigating large craft in fog or heavy weather. Only radio can reach ships in such circumstances, aud this science has been so well developed in the last six years that it is possible to navigate in such dangerws waters as the English Channel at normal speed without fear of grounding. Nearly a dozen radio beacons on both side of the channel have enabled navigation to be carried out with a remarkable degree of accuracy, owing to the chain of cross-bearings by which to pilot their course. On the New Zealand coast ‘the first consideration is that of finding ports and rounding capes in thick weather. It is understood that after Baring Head beacon has been. completed arrangements will be made for the transmission of direction-finding:signals from Stephen’s' Island also, at four-hourly periods, on request through Wellington from vessels ‘coming from Australia and the north-west coast. This will be a useful supplement to the regular service from the eastern side of Cook Strait. If an area near the radio beacon is well sounded, a navigator may combine the radio and the :chart to round the coast, a schedule to keep to, and

find an almost exact position by the reception of two or three signals from different points along the route. The further away the ship may be from the beacon, the greater the liability of error in position .calculations, but generally speaking the: radio beacon service even to-day is an invaluable aid to.strangers on a strange coast. pa rn Experimentation has‘opened up a wide field of study in this department of radio science, and the several types of practical radio fog signals so far evolved suggest that within’a few years the work of investigators will be finished. An ingenious installation has -been made on Little Cumbrae, at the ‘mouth of the Clyde, in Scotland. A blast on the air-fog signal is given simultaneously with a signal from the radio beacon, and the sound signal is timed precisely by a gramophone record, which counts out the sound in cables’ lengths instead of seconds. So the navigator listening-in hears the radio flash indicating that the sound signal has been: made, and when the air-fog signal: reaches the ship he notes the count in distance being made over the radio, thus having an almost instantaneotis calculation of both direction and distance in relation between the ship and the beacon, if his ship has a radio direction-finder. The only other set of the same design at present is in the China Bakir River, at Rangoon, for although this equipment sounds sufficient to the layman, technical met: consider it to be still-in the experimental stage, ~ This type is not thought suitable for New Zealand. however, as it requires more attention than it is worth under our conditions. Another effective type is fitted with a rotating frame aerial. A signal is made when the directional beam is due north, and the subsequent series of longer signals provides the direction. of the beacon to ships in a complete circle as they time the steady rotation with special stop-watches. The Orfordness radio beacon on the English coast is of this type, signalling for four minutes and remaining silent for eight. "Half the worry in navigating is to know what line you are on," said a Wellington master mariner. "With the combination of beacon and soundings ships will know just where they are. One of the ‘beauties of the Baring Head beacon will be that when coming down the coast ships will be able to get a bearing on the head and know when they are past (Continued on page 50.)

Radio Beacons Aid Mariners in Fog (Continued from page 14.) Cape'Palliser. On the other side theywil be safe from Cape Terawhiti, and those coming from the south will have no fear of running into Palliser Bay. Air-fog signals will always be required, © of course, and ships will still have to keep a look-out for one another, but one ‘might say that navigation by a radio beacon in, thick fog will be as easy and simple as navigating by a lighthouse at night." So radio hds added a still: greater margin of safety to trayel by sea, for it has all but laid for ever the "menacing spectre-"‘fog in the fairway. 7.