SAFETY DEVICES

Evening Post, Volume CVI, Issue 90, 13 October 1923, Page 24

SAFETY DEVICES

FOR BRITISH RAILWAYS

GREATER SPEED ACHIEVED

FEWER LIVES LOST.

The safety of the British railways has long been cause for just pride amongst oar railway engineers, and the confidence •which is. reposed by the travelling public in the railway workers, whoso everyday duties necessitate the shouldering of such heavy responsibilities, is certainly not Misplaced. ..These statements are justified by the annual returns recently published by His Majesty's Stationery Office of the accidents and casualties-reported by the several railway companies in Great Britain during the year ending 31st December, IJJ22, comments the engineering correspondent of the "Daily Telegraph." The statistics there set out deal with passengers and servants of the companies in separate categories. They also -separate casualties caused by the running of trains or the movement of railway vehicles, from those of servants of the companies and contractors killed and injured otherwise than in accidents to trains or by ths movement of railway ■vehicles. From so extensive a system as that of industrial Great Britain large figures may well be anticipated. The returns, however, show some very satisfactory features.. ' ' "

••During-1922 five-passengers were killed and 406 injured, as compared with eighteen killed and 539 injured during 1921, through accidents to trains. From the same causes four servants lost their lives and eighty-three -were injured (injury involving more than, a day's absence from work) in 1&22, as compared with ™n bitted and seventy-five injured' in .}■ From other accidents- connected ■with-the running of trains 203 sei-vants ■were killed and 2864 injured in 1922 as compared with 217 killed and 2755 I"j?'ed in IS2I. As the 217 figure for 1&21 constituted a record figure since returns wore first published in 1871 the figure of 203 for last year most be regarded as eminently satisfactory when it is remembered that there was during that year an increase of 16 per cent in engine miles. ......'.

-Not only is there the increase in engine' miles, but tha modern trend towards greater speed cannot be overlooked. A notable-example from recent history is. that of- the -3.45 p.m. train irom Swindon to Paddington, which is now scheduled to do its 77£ miles in seventy-five minutes, at an average speed of .61.8 miles per hour. On the first run this speed was easily exceeded, "and in fact, 65.28 miles per hour for the whole journey was attained. Again, long-dis-tance trains at high speed are illustrated by that running from King's Crcsa to Leeds, where an average speed of 56 13 miles per hour was attained from King's Cross to Doncastei-, and an average of 53.33 miles per hour from King's- Cross to Leeds. Abroad there is the reported run of a Paris to Boulogne special on the Pans-London service, in which the distance of 159 miles was covered in two hours five minutes, giving an average speed of seventy-six miles per hour In these advances safety first has still to be the. watchword, ami this depends on three chief factors, the highest standard of rolling stock, efficient signalling and lastly, but perhaps most important, the human factor which operates all the controlling and safety devices. THE BLOCK SYSTEM. The fundamental principle of railway signalling m to maintain suitable distances between moving trains, and by a system of telegraphic communication and semaphore control to prevent any "^ faction of such intervals. -the block system as used in double hne workmg practically all over the world ,s the most efficient method S o lv i7lfl° T a<; compli^in S this- Briefly the block system consists of subdividing a^ 6 t retch of railway into convenient sections the length of these "depending on the traffic density A signal-box controls each section, and tions two trains are not allowed in the same section at one time t/on ' enterS> aDd leaV6S the se=This does not infer a moving indicator thgTl *U\ lt poSsiWe reading 8^ instruments in the signal cabin to realise at once if there i s a "train on lino ,n the section, if the "line is clear through the section, or if the indication is «lme blocked." The work ing detail of the block system is simple most porters at wayside stations soon acquire a working knowledge of it by casual visits to the cabins. It requires little more on the part of the signalman than the repetition, of. certain mechanical movements.- This, however, o»]y applies to ordinary through-track workin" The handling of traffic at busy iunc tion s and terminal stations is a-totally different matter, calling for skill, alertness, and sound judgment if delays and minor traffic dislocation are not to occur It is well known that a system of interlocking exists by which the.road and the signals controlling the passage of trains over it are linked together. Thus the signals pertaining to a branch line can only be lowered when-the points are open for the branch. Similarly, no tram approaching a junction can be given, a clear road by signals through the junction if the road is set in sudi a way that a train on the opposite metals' could enter a branch by crossing the junction. ° The locking of the "caution" distant signal with the home signals is intended to prevent a driver reaching a stop signal at danger without previous warning. LOCK AND BLOCK SYSTEM? Becent developments have resulted in the interlocking- of the telegraphic "block instruments with the semaphore control system. This is intended to prevent the occurrence of accidents duo to lapse of memory on the part of signalmen. _ A train delayed at a starting signal is always an item of danger in the old system; it is largely dependent on the signalmen's memory for its safety. To protect such a train collars were supplied which slipped over the catch bar on the home signal lever, thus preventing the home signal at the rear of tho train being pulled off without removing the collar, and. hence recalling the train to the signalman's mind. These devices are too often used as paper-weights, and are frequently entirely neglected for the purpose they are supplied for. An accident caused in the above way occurred at Hawes Junction, on the old Midland' system. Two light engines, ■which had banked a heavy train, were taken off at Hawes and put over on to the south line to return to Hellifield. They were left standing at an advance starting signal, and were run into by an express train from Carlisle with disastrous results.

The new lock and block system protects a train from accidents of this kind by making it necessary to lower the starting signal as well as the home and distant before a second train can be accepted into a section. This means that for each train accepted a clear sig-

nal way must be given throughout the section before another train can be admitted. This prevents a train standing in a section being run into by another train admitted accidentally to the same section.

The second train could not be accepted on the block instrument until the first train had cleared the starting signal, and was, therefore^ proceeding into the advanced section. , This system seefns to approach Ino ideal of. the signalling engineer, insofar as it practically prevents a signalman mishandling traffic without a deliberate intention to do so.

It has one weakness, and that is, whilst protecting the train against errors on the part of the signalman, it affords r.o protection against any mistakes on the driver's part.

The control of any train is ultimately vested in the driver; he operates the throttle valve and brakes, and, whilst automatic devices are available to aid the signalman in his duties, the human factor on the footplate dominates absolutely the practical control of the train. One would anticipate that if, in future, accidents occur, when the installation of the lock and block system and its accessories becomes more universal, the error will lie chiefly with, the driver.

Drivers of express trains carry a greater weight.of responsibility unaided than is often realised. The driving of a modern express locomotive leading a heavy train is a difficult technical task in itself, but when to this must be added the responsibility of ' watching the road signals, one can only admire in silence.

There appears to be- a need for some means of communication between the driver and the signalman. Periodically accidents have occurred where a signalman has had the desperate situation thrust upon him of watching an "express train rush into certain danger and possessing no means of attracting- the driver's attention. Accidents of this type could be enumerated. One occurred recently on the London and North-Eastern Bailway at Betford, where a train failed to draw up at the stop signals and the signalman was unable to warn the driver. It is suggested that here lies one of the main points of weakness' of the present signalling system:" The' possibilities of wireless in this connection may some day offer a complete solution, but until that time the need for some simple device is obvious..

A more extensive use of the fog signal detonator-placing machines would be of much value in this direction. Operated from a. draw-lever in the signal-cabin, these appliances could be fitted near the last stop signal in each section on both sets of metals. Alany British companies have installed those devices to a limited extent principally to facilitate working during fogs. The universal installation of. the appliance would, however, serve both as a means of -working traffic in areas whero foggy conditions may- occur suddenly, and also as a protection against the driver over-running stop signals. .... i

■A monthly test of the device with an entry in the section log-book; would familiariso signalmen and drivers -with its operation, and pave the way for its lisa in an emergency. Such an accident, as that which occurred at Aissrill in 1912 would be prevented, and the fitting of such devices throughout all railways might well have been the lesson of that disaster.- Generally speaking, no railways in the world are worked with a greater degree of safety than those of the British Isles a tribute first to the .engineers and inventors -who have fitted and devised such excellent control appliances, and. secondly i n perhaps a greater degree, to the ability and efficiency on duty of the loco men and signalmen, who are responsible for their working under tho stress of modern railway practice.