Riddles 9F 2-10-0 Speedometer

[Wickham Green too]

Maybe someone actually twigged that it might be a good idea to be wary of speed limits before higher C.o.G. locos went into traffic !!?!

[uax6]

On 29/01/2023 at 20:55, Ramrig said:

This is a shot of 92214 at the GCR gala last Friday. Is that a Speedo connected to the first tender axle?

it may be a preservation addition. 
 

Is the leading axle off a class 40, thereby allowing the speedo to be fitted to the tender relatively cheaply? It looks like a very sensible and subtle way of doing it.

 

Andy G

[LMS2968]

The leading - non-powered - axle of Class 40s had inside bearings so couldn't be used in this location. Nor did they have any provision for a speedo drive.

[uax6]

Sorry, I meant the leading axle of the tender! It would have to be the middle CO axle of the class 40 to have the speedo drive...

 

Andy G

[Wickham Green too]

The axle could be off a class 40 - but the wheels aren't as the tender seems to be sitting level !

[eldomtom2]

On 31/01/2023 at 22:20, hexagon789 said:

BR adopted the LNER system, but I believe we would be into the 1960s before all surviving lines were equipped.

BR initally rejected adoption of the LNER system across the entire network on the grounds of cost, but changed their minds after 17 people were killed in the 1955 Sutton Coldfield accident, where a diverted express train derailed while doing 60mph in a 30mph zone. The Recommendations section of the accident report provides a good insight into the thinking at the time:

Quote

75. There is at least a strong possibility that the accident would have been prevented by lineside speed restriction notices or signs, acting either as a direct reminder to Driver Allen on the afternoon in question, or indirectly by impressing the location and severity of the restrictions firmly in his mind as he passed the signs regularly during his working of stopping passenger trains over the route.

76. Speed restriction signs have not heen a general feature of British practice in the past, though some of the former Companies, notably the Great Western, provided illuminated notices of various types at places where it was considered that a speed restriction required special emphasis or where there were no distinctive physical landmarks by which a driver could locate himself accurately. The London and North Eastern Company, on the other hand, decided to mark all permanent speed restrictions by simple "cut out" numerals on iron posts by. the side of the line, but they were not illuminated at night. Before this decision was reached there was some divergence of opinion on the usefulness of these signs, but experience has shown that they are of value to men learning the mad.
No change was made on nationalisation, but the whole question was considered by the Railway Executive in 1949, when it was recommended "that indication signs be provided on the lineside at the commencement of restriction at places (1) where there are no landmarks to identify positions and (2) where there has been experience of persistent excessive speeds"; it was held that the illumination of such signs would improve them but that this was not essential. After consideration of this recommendation it was decided that no action should be taken at that time in view of the prevalent restriction on capital expenditure, but a few illuminated signs have since heen provided to meet special circumstances.
77. This then is the position today, and the observance of permanent speed restrictions in this country has depended in the main on a thorough and intimate knowledge of routes by drivers, as confirmed by their signatures on the route cards, and of the printed instructions such as the Appendices to the Working Timetables which lay down the restrictions to be observed, British railway managements have always been strict in requiring drivers to have a thorough knowledge of all the routes on which they are required to work, and no obstacle is placed in the way of men who may request "refresher runs" over any of the routes. On the whole this system has worked well in practice, as this was the first case for 24 years of a serious derailment caused by disregard of a permanent speed restriction on plain track. The last occasion was at Canal Junction, Carlisle, in 1931, and the only other serious accidents of this type during the present century were at Aylesbury in 1904, Salisbury in 1906 and Shrewsbury in 1907; I exclude derailments caused by excessive speed at diverging junctions or at facing crossovers between parallel lines which are in a different category as they are due in the main to disregard or misinterpretation of the fixed signals.
78. British Railways, however, are now entering an age of more precise working, with diesel and electric locomotives fitted with speedometers, as also are all new passenger and mixed traffic steam locomotives. It should therefore he possible in the future to regulate speeds more closely to permissible limits, and there is little doubt that as a result the civil engineers will be pressed to raise their restrictions as much as possible. Higher maximum and average speeds are also envisaged. Furthermore, the training of the driver in the future will probably he different from what it was in the old steam days, with fewer years of running experience, and engine runs may be longer with a greater strain on memory to recollect all the features of a route. Nor should it be overlooked that, with the more intensive use of engines, drivers are now required to have a knowledge of more routes than in the past. All these factors make it necessary to consider whether the past general practice of relying on memory for the observance of speed restrictions should not be changed, and a uniform procedure adopted for defining clearly the position and degree of speed restrictions by lineside signs. I recommend that this question should again receive the attention of the British Transport Commission, and at the same time I would observe that the practice of the former London and North Eastern Railway of using unlit signs at the beginning and end of restrictions has much to commend it.

 

Edited February 16, 2023 by eldomtom2

[The Johnster]

Smoke deflectors are usually used where the combination of a large diameter boiler and hence smokebox results in a short chimney to keep within the loading gauge, meaning that smoke and steam are liable to hang over the boiler obscuring the crew’s view ahead rather than lifting clear of the loco.  This can happen at quite low speeds, and the headwind created at even 15mph is palpable, as any cyclist will affirm, so deflectors or any form of smoke lifting will be effective at goods train speeds.  And certainly at S&DJ passenger summer timetable speeds!
 

More of a mystery IMHO is that, when some Britannias had the smoke deflector handrails removed following the driver’s claim to the inquiry into the 1955 Milton accident that the handrail had obscured his view of a GW signal sited on the rh side of the track, the Clans, DoG, and 240 9Fs (not the Crostis) retained theirs, with no further signal sighting issues that I know of.   Presumably the Board of Trade investigators must have verified the driver’s claim, surely!  The Thompson and Peppercorn pacifics had similar handrails as well.  The Southern and LMS used handgrab holes, as on the altered Britannias, but some WR Britannias were overhauled after the Milton report and retained the handrails, 70021 Morning Star for one.  I have never read that the LMS and Southern handholes were used because of sighting problems from handrails, but this may have been the case.  If so, the LNER and BR were not following established best practice!  BR continued Southern practice with the rebuilt Bullieds.  
 

Note that, unless the dial is backlit as on Bullied pacifics, a speedometer can not easily be read at night, and if the firebox door is in use, drivers will not look inside the cab unless they have to, in order to preserve their night vision.  Speedometers on steam locomotives without electric lighting are therefore of limited use at night.  Drivers assessed their speed by experience and noting passing times at signalboxes, knowing how long the WTT allowed them through sections on each class of train, easing off a bit if they came in under time and opening up a bit if they were over time, a time-tested and reliable method even at night.  A locomotive with the same load on the same job worked in the same way day in day out is going to turn up at the same time or within seconds of it every day anyway.  
 

Running to time at the required booked speeds is not just safety; running outside these timings, too fast or slow, affects pathing delays other trains, and blocks junctions.  I once heard the job described as not driving the train, but ‘stopping the train at the correct places and times as shown in the WTT’.  When you think about it, this covers all bases; you have to make the train go at the booked speed to be able to reach the correct place at the correct time to stop it at said correct place and time as shown in the WTT!

Edited February 19, 2023 by The Johnster

[45125]

On 15/02/2023 at 17:26, Wickham Green too said:

The axle could be off a class 40 - but the wheels aren't as the tender seems to be sitting level !

The speedo generator is more than likely off a 37, and the drive peg for it will be fitted on a plate that is fitted on the axle end.