THE LIFE-BOAT FLEET Motor Life-boats, 138 :: Pulling & Sailing Life-boats, 29 LIVES RESCUED from the foundation of the Institution in 1824 - 65,396 to November 30th, 1937 Radio Telephony in Life-boats.

By Engineer-Captain A. G. Bremmer, O.B.E;, R.N., Superintendent-Engineer to the Institution.

WIRELESS ' has now been in use in life-boats of the Institution for eleven years, but the severe limits of its use, and the great difficulties of its use, in life-boats are hardly understood by those who have seen the spectacular results of wireless in bringing help to vessels in distress on the high seas, and who think that, as a matter of course, all the Institution's life-boats should be equipped with it.

The use of wireless in life-boats is solely for the purpose of keeping them in touch with the shore when they are out at sea and are too far away for visual signals to be seen. They have not the duty of picking up messages from vessels in distress. That duty belongs to the shore stations, of which the General Post Office now has thirteen round the coasts of the British Isles.

There are also a number of lighthouses and light-vessels, offices of Harbour Authorities, and a few coastguard stations, which have radio-telephony sets both for transmitting and receiving.

It is the shore stations which receive signals of distress. These messages are passed through the coastguard to the life-boat stations, which act upon them.

In the same way, if a life-boat station wishes to communicate by wireless with its life-boat at sea, it does so through the shore station.

A Fifty Mile Radius.

The first limit on the use of wireless by life-boats is that there must be shore stations which can communicate with them, and the shore stations have low-power transmitters. At first they had to be within fifty miles of the life- boat station if they were to be able to get into touch with its life-boat.

Now, with more modern sets ashore and in the life-boats, it has been found, in some cases, that considerably greater ranges are possible.

Again, those who are able, with simple receiving sets in their homes, to hear distant broadcasting stations without any difficulty can hardly realize the difference of taking messages in a life- boat at sea, when it comes, not from a powerful broadcasting station working on 50 to 200 kilowatts, but from a trans- mitter with a power of only a fraction of a kilowatt, and when that message has to be heard in the midst of the noise of wind and waves and the life- boat's engine. The difficulties of re- ceiving are also increased by electrical interference from the engine and by the impossibility of having on a life-boat masts sufficiently high to carry really effective aerials.

The First Experiment—1927.

The Institution began its experiments with wireless by installing a wireless- telegraphy receiving and transmitting set in the Rosslare Harbour, Co. Wex- ford, cabin motor life-boat, in 1927.

This life-boat might be at sea for a long time standing by local fishing boats.

The purpose of the wireless was to inform her while at sea of vessels in distress elsewhere. If such a message reached the life-boat station, it was telephoned across the Irish Sea to the wireless station at Fishguard in Wales, and wirelessed by that station to the life-boat at sea. This station has since been closed, and messages for the life- boat now go by way of Land's End Radio. This is the only life-boat which has been equipped with wireless tele- graphy. It has not been used in other life-boats, because of the necessity of carrying a fully certificated operator.

In 1929 the next step was taken when the motor life-boats at Dover, Storno- way, in the Island of Lewis, and St.

Peter Port, Guernsey, were equipped not with wireless telegraphy, but with radio telephony, and a little later the motor life-boats at New Brighton, on the Mersey, and Barra Island, in the Hebrides, were also equipped with it.

These five life-boats had both receiving and transmitting sets with a range of fifty miles.

At that time the Post Office shore stations had wireless telegraphy only.

There were very few shore stations at all with radio telephony, and these were of very low power. Then, in 1931, the Post Office equipped its shore stations with radio telephony of low power.

The Difficulty of Protecting from the Sea.

The six life-boats which had by this time been fitted (one with wireless telegraphy and five with radio tele- phony) were the only life-boats which fulfilled the necessary conditions. They were within fifty miles of a shore signal station, they were life-boats with cabins, and they lay afloat. Those second two conditions were as necessary as the first.

T?hey kad to lie afloat, so that the mast and aerial could be kept up for regular testing. This could not be done when the life-boat was hauled up into a boat-house and the mast had to be lowered, and without this it was not then found possible to maintain the apparatus. They had to have cabins to protect the delicate apparatus from the sea. Even with cabins the damp caused great difficulties in the first three life-boats in which radio telephony was installed, and the sets had to be refitted and rebuilt. They have since proved very efficient. Such were the severe limits imposed on the first use of radio telephony in life-boats.

The Problem of Housed Life-boats.

As other motor life-boats were built which fulfilled the three necessary con- ditions they were equipped with radio telephony. Up to the end of 1936 nine more had been so equipped. One of these boats (Yarmouth, Isle of Wight) was destroyed in the fire at a building yard last June, where she was re-fitting.

Like the first five, these nine were all cabin life-boats lying afloat, with the exception of Cromer—a cabin boat kept in a house.

In 1936 experiments were carried out with a radio-telephony set in the Cromer boat, to see if, with improved apparatus, it could be used in a cabin life-boat which did not lie afloat.

These experiments were made with a substitute aerial in the boat-house, with which the apparatus could be tested each week. The results of this experiment, though not entirely satis- factory, have been sufficiently good to justify the Institution in deciding to fit with radio telephony all cabin life- boats which are kept in boat-houses, provided, that is, that they are within fifty miles of shore wireless stations.

This has added another thirteen to the number of life-boats carrying both transmitting and receiving sets. These have all been fitted during 1937.

Experiments with Non-Cabin Life-boats.

There remain the motor life-boats which have not cabins. Receiving sets built by amateurs are being tried in the Hythe and Hastings life-boats (both without cabins), and the Institution is now testing in the Aldeburgh life-boat a smaM receiving set, the radio part ofwhich has been built by the Evrizone Radio Company to the Institution's requirements, while the arrangements for making it water-tight have been designed by the Institution. There is no space for transmitting sets as well in the non-cabin life-boats, but the chief importance of radio telephony to life-boats is that they shall be able to receiv e messages from the shore.

Watertight Loud-speakers.

In 1937 a number of cabin life-boats have been fitted with water-tight loud- speakers on deck, so that the cabin has only to be used in sending messages, and these loud-speakers will eventually be used with all sets in the cabin boats.

They are, however, too heavy and cum- bersome for general use in the non- cabin boats.

The types of receiving and trans- mitting sets which the Institution is using in its cabin life-boats are those made by the Marconi International Marine Communications Co., Ltd., the International Marine Radio Co., Ltd., and Coastal Radio, Ltd. It proposes also to test sets by Gambrell Radio Communication Co., Ltd. These sets, instead of being bought, are now rented, the makers undertaking to maintain them. Receiving sets made by Invicta Radio, Ltd., are also being fitted to replace, where necessary, the re- ceivers in the earlier sets, which had been bought outright.

The present position is as follows : Of fifty-three cabin life-boats in the In- stitution's fleet, one has wireless tele- graphy for receiving and transmitting, twenty-six have radio telephony for receiving and transmitting, and another ten will be fitted with it during 1938.

Five cabin life-boats now under con- struction are to be fitted with it and eight more which are to be laid down during 1938. Of the motor life-boats which have no cabins, two are now fitted with amateur experimental re- ceiving sets and another with the Institution's experimental receiving set.

Upon the result of the experiments with these three sets will depend the exten- sion of wireless to other motor life-boats without cabins which are within range of shore stations..