The LMS Ro-Railer

The following article appeared in Railway Wonders of the World published on 21st June 1935. Darren Kitson provides a word warning when using archived material from such sources. He points out that most articles are not objective assessments of the item being reviewed as they are often published at the time of their launch and consequently the claims of achievements and benefits are provided unchalleged by the relevant PR department.

COACHES FOR ROAD OR RAIL

Experimental Services Designed to Speed-up Travel

Introduction

If a broad view is taken of the transport conditions of most civilized countries having the usual road and railway facilities, it must be agreed that the road motor vehicle, whether it is used for passenger carrying or for goods conveyance, has some definite advantages over the rail vehicle. It is not limited to a single track between two fixed stations. The motor vehicle can carry its loads over a network of roads from door to door, without the necessity of transhipment. Further, its use is generally independent of any other ordinary road traffic, and it can start at any convenient time without affecting other road services. The railway goods or passenger vehicle, on the other hand, must keep to its own track and also to a timetable arranged to keep the track clear at certain specified times only. Moreover, the railway station or goods depot is often a considerable distance from the destination of the passenger or goods, and some supplementary form of transport becomes necessary. With goods traffic, the usual procedure is to load the goods intended for transit on to a motor lorry, convey these to the railway depot, and unload them on to the railway trucks or vans. After reaching the nearest station or depot on the railway line the goods must be unloaded from the railroad on to another motor vehicle, conveyed along the roads to their destination and then unloaded once more This method of goods conveyance not only involves an appreciable loss of time in transit, but also necessitates two loadings and unloadings, with the added risk ot damage during these processes ; moreover, it necessarily adds to the cost of transport.

In view of these disadvantages it might be thought that to use the railway at all is a doubtful policy where small quantities of freight of, say, two to four tons are concerned, when the goods could be conveyed from door to door without employing the railway. The answer to this is that in partly developed districts, and in areas where the roads are either bad or are congested, it is very much quicker to send goods by rail. The speeds employed on railways are normally much higher than those on the roads. For long distance work, also, the advantages of rail transit are indisputable ; moreover, the transit costs are lower. In many undeveloped or partly developed countries there is generally a railway joining the main towns or industrial areas, and a network of roads leading to the railway stations and depots but there are few long distance main roads And it is here that the railway scores over the road vehicle ; for the latter cannot be used without suitable roads. From these considerations it seems that in its own sphere of operation the motor road vehicle and the railway vehicle each possesses definite advantages.

With a knowledge of these facts it is not surprising that transport engineers have considered the possibility of designing a new type of vehicle that will combine the advantages of each type while avoiding its drawbacks. After a careful study of this problem, combined with a good deal of research work, a suitable vehicle, known as a "road-railer," has been evolved. This can run equally well on either the road or the railway track. It can thus begin its journey by road from the loading place to the nearest railway station, and then transfer to the railway lines, becoming for the being a rail-coach. At the end of its railway journey it is once again transferred from the railway track to the road and thence driven off, just as any other motor vehicle, to its destination. It may be of interest to point out some of the more important uses of this combination vehicle. Its particular application is on branch lines and, especially, on those branch lines where towns and villages lie some distance from the railway. Passengers or goods may be taken on at any convenient place, wherever there is a suitable road. New or partly developed districts lying some distance from the railway can thus benefit materially from the use of the road-railer. Further, the possibility of using this vehicle for week-end and other abnormal traffic must not be overlooked. Road congestion, leading to both slow and dangerous travel, has often created a problem which this new type of vehicle at once solves. Both types of vehicle-passenger and goods-can be attached to trains, with the added advantage that they can be detached when required to proceed to their destinations as ordinary road vehicles.

Apart from its advantages to the railway authorities, the road-railer may be used in various Government services. Its utility in countries where, during certain periods of the year, the rains are so heavy that the roads become impassable, will undoubtedly be recognized, for it will then be possible for journeys to be made over the permanent way. On the other hand, should a portion of the track be destroyed, or under repair, it is then possible to divert the road-railer on to the road and return it later to the track at the other side of the part which is out of commission. It may even be an advantage to use the vehicle over long distances by rail, and then to cut across country and afterwards connect up with another railway, without having to unload and transfer the goods, as must be done with conventional vehicles. Perhaps the greatest advantage of the road-railer for use in developed countries, such as Great Britain, is the rapidity and economy with which passengers and goods can be transported over medium and longer distances, from sources and to destinations remote from the railway station.

From the point of view of the passenger service, the low tractive effort necessary to propel the vehicle on the rail results in much lower running costs, due to the reduced fuel consumption and absence of pneumatic tyre wear ; this should involve lower passenger fares. Again, when on the railway track the road-railer is capable of travelling, with safety, at higher speeds than it can attain on the roads ; thus, with the Karrier road-railer speeds up to sixty miles an hour are well within the engine's capacity. Further, it is much safer and easier to drive a road-railer on the railway lines than on the roads, for there are practically no obstructions on railway lines. From the point of view of the passenger's comfort, the road-railer has the advantage, well-known to users of motor-coaches, of combining first-class seating with third-class fares. Again, where the railway is the shorter distance between two towns, a certain amount of time is saved. As a goods vehicle the road-railer not only avoids duplicate loading and unloading, but also, owing to the lower fuel costs on the railway track, and to the absence of tyre wear, proves to be more economical than other types of road vehicles.

The LMS Karrier Road-Railer

The various advantages outlined above are embodied in the Karrier road-railer about to be described. This vehicle represents the results of over two years' experimental work. The first production model was delivered to the London, Midland and Scottish Railway. It was in the form of a twenty-six seat passenger coach, and complied with the Ministry of Transport's Regulations, as well as those of the railway authorities. Large capacity double-deck passenger vehicles can also be built. The range of road-railer freighters is from 30 cwt. to 8 tons, if complying with the Ministry of Transport's Regulations, but for service abroad they are available from 30 cwt. to 20 tons. The vehicle which ran experimentally on the LMS. is fitted with a six-cylinder petrol engine of the usual commercial motor-vehicle design, rated at 37.2 hp, It has a wheel-base of 17 feet 1 inch, and road wheel track of 6 feet 3½ inch The rail track is the standard 4 feet 8½ in. gauge. The transmission has a top-gear ratio of 7 to 1 for road use, and 4.2 to 1 for the railway track. These ratios give maximum speeds on the road and rail of 60 and 75 m.p.h., respectively. The petrol consumption on the road is 8 miles per gallon ; on the railway track it is 16 miles per gallon. The total weight of the vehicle, unloaded, is 7 tons 2 cwts ; 3 tons are allowed for the weight of the passengers, staff, and luggage.

The following is the method employed in this ingenious car for converting the wheels from the pneumatic road type to the steel-flanged railway pattern. Flanged rail wheels are fitted to the vehicle's axles ; on the outside of these are placed pneumatic-tyred road wheels, each of which is mounted on eccentrics fitted to an axle extension through the rail wheel. When on the road, the road wheels are locked concentrically to the rail wheels, which, being of smaller diameter, are quite clear of the road. The wheel changing operation is as follows. For road to rail transference, the "road-railer" is driven on to the rails at any place where the road has been made up level to the rail tops. Then, with the rail wheels directly over the lines, it is driven forward a few yards until it reaches a point where the made-up road is tapered off. The rail wheels now gradually come into contact with the rails, and take the weight of the machine off its road wheels. The road wheels, which are mounted on an eccentric device, are then raised above rail level by the action of the driver, who rotates them on their eccentrics and locks them to the chassis frame by means of a pin. The road wheels, therefore, do not rotate when the vehicle is moving on the rails. The "change-over" operation is, of course, reversed when returning to the road.

The same principle holds good for both the front and rear wheels of the vehicle. The components are generally interchangeable on all four wheels. Two eccentrics per wheel are employed in this particular design, which enables as much lift to be obtained as is allowable by the wheel rim diameter. The operation of lifting a wheel of the necessary dimensions requires little manual effort. Further, when the road wheel is in a lifted position there is only one bearing in the mechanism which possesses any velocity relative to the main hub. In other words, all the road wheel mechanism remains stationary while the road wheel is out of action. The rear wheels are driven by a propeller shaft in the same way as an orthodox road vehicle, and the drive is cut off from the road wheels by disconnecting two pins which are utilized to secure the road wheels in an eccentric position to the slipper block structure. This structure-one for each wheel-is a device which provides support for the road wheels in their raised position while permitting vertical relative movement between the axle and the frame when the vehicle is on the rail. The structure is hinged in two places, and folds into the body when the vehicle is used on the road. It also offers, due to its radius from the centre of the axle, the required resistance to overcome the static friction between the wheel hub and the inner eccentric bearing. There is no load either on this slipper block structure or on the pins, except that immediately required to overcome static friction between the inner bearing of the inner eccentric and the driving hub when beginning to move on the rail. The pins, however, are of ample dimensions, for they are the medium through which the road wheel drive is taken when the vehicle is running on the road.

It is impossible to insert these pins in the wrong position when raising the road wheels, as the horn block slipper covers up the driving pin hole which is not required and exposes the one into which the pin is to be inserted. The construction of the horn block slipper is unique. It has in its body an automatic lock which prevents the pins from becoming loose when any small vibration is experienced. While this object is satisfactorily achieved, the construction is such that with a minimum of effort, applied sharply, these pins may easily be withdrawn. A similar device is incorporated on the driving hub flange when the pins are inserted for road work. Very long pins ensure that the drive is distributed over wide centres, and their diameter is such as to render wear on the pin bearings highly improbable, on account of the small intensity of pressure to which they will be subjected. When the road wheels are driving, the rail wheels also are revolving, the connection being made through the outer portion of the hub end which is keyed on a taper to form a connection between the hub and the driving wheel. The wheel bearings are of the adjustable taper roller type. Another interesting feature is the adoption of the Lang-pattern laminated wood wheel, which possesses both resilience and exceptional strength, and assists greatly in the elimination of track noise. Detachable and renewable steel tyres are employed on these wheels.

As the vehicle runs up to the rail it is impossible to guarantee the position that the driving pins of the road wheel will occupy in relation to the holes in the slipper block. Provision is therefore made whereby the inner eccentric may be positioned in relation to the slipper block. Having established this position it then becomes necessary to ensure the correct relationship between the inner and outer eccentrics. For this reason two slots are provided in the inner eccentric into which the single plunger may operate. After the position of the inner eccentric is located the wheel may be swung round the periphery of that portion of the mechanism. And, when the outer eccentric has assumed its correct radial position in relation to the inner eccentric, the plunger, which has previously been withdrawn automatically from its original slot, now becomes engaged with. a slot. This slot has been correctly positioned by its relation with the lower slipper-block pin. This ensures that the two pin holes are in line one with the other, and also in a correct relationship with the holes in the slipper block. It will be seen, therefore, that it is impossible to swing the outer eccentric past its correct centre. The condition is now one in which the inner eccentric is prevented from rotating by the lower pin, while rotational movement of the outer eccentric is also prevented by the upper pin and the spring plunger. It should be made perfectly clear, however, that the two pins substituted in the slipper block are in a position which definitely has disconnected all the drive from the hub to the road wheel of the vehicle in question.

The chassis of the road-railer generally follows conventional commercial vehicle practice. The gear-box, however, is provided with an additional over-speed arrangement to permit of a higher top gear (4.2 to 1), when travelling on the railway, than that used on the road (7 to 1). The braking system serves equally well for both road and rail operation ; on the railway, of course no skidding is possible when the brakes are applied. The vehicle may be stopped in a very short distance from speeds of forty to fifty miles an hour without the danger of wheel-lock. The tractive effort is ample, and permits the towing of other vehicles. The rear rail wheels are provided with sanding gear. Buffers are provided at both front and rear, special supports for these being anchored to the main chassis frame. There is also a spare wheel carrier fitted at the rear of the chassis. This is mounted on rollers, and it slides automatically to the ground upon release of the attachment fittings. Automatic lubrication is arranged for all the working members of the chassis.

The LMS Ro-Railer

The following article was originally published in Stratford upon Avon Transport Notes - Volume 02/04 by J R Jennings SMJR line archivist

I have been researching and lecturing on the Stratford upon Avon and Midland Junction Railway for over forty years. It is incredible how many times I am asked about the “Ro-Railer”. This vehicle only served in revenue service for a few weeks. It has taken on almost mythical status and although it deserves a place in history its main contribution to Stratford is that it put the station at Old Town and the LMS railway as an alternative route clearly in front of a much wider public than it had ever previously enjoyed. Not since the days of the “Harvard” special trains in the pre-Great War era did so many people crowd onto the 'other' Stratford station as on the morning of 23rd April 1932. I estimate that more photos were taken of the Ro-Railer (and certainly more survive) than of any other ex-SMJR line subject. If only the unique Fairlie engine had enjoyed similar status! This short volume has been edited over the years as new data has come to light. It draws together information that appears in many sources elsewhere.

The Stratford upon Avon and Midland Junction Railway and the LMS Railway that took it over in 1923 made various attempts over the years to offer a through connection between Stratford and London. The rival GWR route with a change at Leamington Spa was longer than either the Stratford - Marylebone or Stratford - Euston possibilities that existed using the SMJ route. In the early 1900s a through service was provided by a coach that was worked over the SMJ line before being attached to a Great Central Railway London service at Woodford. This involved the coach being 'trip worked' from Byfield to Woodford and back. Its progress over the SMJ line to Stratford was slow because it was attached to a normal all stations stopping train. The Railway 'grouping' of 1923 put the Great Central Railway in the LNER camp with the SMJ becoming part of the LMSR. This really ended any future cooperation on through coaches via Woodford. The 'gateway' from the SMJ line to London had always been via Woodford because when the GCR London extension was built the need to generate traffic was paramount and the layout at Woodford took account of interchange traffic with the SMJR. The LMS could direct traffic to its West Coast Main Line at either Blisworth or Roade. The connection at Roade had never been fully utilized even for freight but the interchange at Blisworth was one of the better used parts of the ex SMJ system and although passengers would need to walk through to the main platforms a reasonable connection to the capital could be achieved. The authors of the various books on the SMJ have never effectively explored why the Roade connection was not developed for passenger through traffic. In mileage terms it was very attractive but the most plausible explanation is that the LMS (and LNWR before it) did not want to stop express trains at a relatively unimportant station to attach/detach through coaches of dubious commercial benefit to them. Some authors have suggested that the track layout at Roade dating from the 1840s and the lack of a shunting engine at all times were also considerations.

During the 1920s competition from road transport was becoming a big problem for all of the railway companies and they explored ways of cutting costs and developing new traffic on loss making lines. The LMS were aware that Stratford upon Avon was an increasingly important destination with the attractions of the 'new' theatre and their own investment in the Welcombe Hotel. Ways of providing a passenger service of reasonable journey time were considered and it was decided to trial a new concept of vehicle that could run on both rail and road. If successful this would have great potential to win traffic for lightly used lines. In the case of the Stratford service it would be possible to convey passengers and their luggage directly to and from the Welcombe Hotel via the SMJ line as far as Blisworth where with just one change of train they would be conveyed directly to Euston. The journey time would be enhanced by the vehicle running non-stop from Blisworth to Stratford although the constraints of a difficult single track line often meant waits at Towcester and Kineton.

The LMS Ro-Railer UR7924 was ordered by the LMS carriage division at Wolverton in Feb 1931. The supplier Karrier Motors of Huddersfield was a surprise to some as they were running down their bus production having earned a poor reputation for reliability in the 1920s. The chassis was a standard Karrier Chaser powered by a 6 cylinder engine with a maximum rating of 120hp. The Chaser was the last serious bus design by Karrier. The body was built by Cravens to their B26C design and featured 14 front facing seats in the forward vestibule and 12 longitudinal seats in the rear smoking saloon. Luggage space was provided on the roof or by folding up some of the seats in the rear vestibule. It weighed 7 tons 2 cwt and was fitted with railway sanding gear, lamp irons and emergency drawgear for locomotive haulage. Loco haulage was limited to 20 mph although apart from the presumed rescue on its demise there is no record of loco haulage taking place. The pneumatic road wheels and traditional flanged rail wheels were mounted on a manually set eccentric arrangement and could be switched from road to rail in under five minutes by one man whilst the vehicle stood over a sleepered crossing. The technical arrangements are dealt with fairly comprehensively in most of the books that have been published about the ex-SMJR line.

After delivery and acceptance at Wolverton it was put on trial on the Hemel Hemstead – Harpenden branch where it was photographed in late 1931 by H C Casserley. In an attempt to gain publicity the LMS decided to allocate this first experimental vehicle to the ex SMJ section and the service was launched at Stratford upon Avon on 23rd April 1932. This is an important day for the town as it is the birthday of William Shakespeare and there would be many influential people and pressmen around on the day. As previously mentioned the LMS had converted a mansion at Welcombe into a Hotel and the Ro-Railer was charged with conveying passengers directly to it without the need to transfer themselves or their luggage at the railway station. There was a minor skirmish with an omnibus company who held the local carriage license and objected to the LMS in effect providing a service on their territory although they did not offer a route from Stratford LMS to the Welcombe hotel! This was resolved by the LMS agreeing to charge a flat rate fare of sixpence (6d) for any intermediate fare stage if passengers were picked up in the town. There were few takers.

The Ro-Railer suffered from the same problems as many early road bus conversions to rail in that it was too light for efficient rail adhesion particularly on a line like the ex SMJ which had the gradient profile of a switchback. It struggled to maintain progress uphill and was then driven hard on the downhill to compensate. (The author experienced a very similar vehicle still in use in Chile in 1993 and the ride qualities were not for the faint hearted!) The lack of effective suspension and springing meant that the hammer blow from rail joints and crossings was transmitted to both machinery and occupants. Early failure of some vital part was inevitable and after a few weeks of operation the Ro-Railer broke a front axle component whilst in service near Byfield. It was removed to Wolverton and never used again as a rail vehicle although the fact that its road registration was renewed for a number of years after suggests disposal for use as a road vehicle. The LMS did have plans to order more including goods/passenger convertible versions for branch line use. These plans were abandoned by virtue of a short minute at an LMS board meeting in late 1932.

In view of its novelty and the launch on 23rd April there is a wealth of photographic material of the vehicle. In addition to the railway coverage the odd shot of it on the streets of Stratford keeps coming to light as residents come forward with a photograph taken by a relative of this 'unusual vehicle' as the local paper had described it. Apart from Casserley's efforts not too many photos of it exist outside of the Stratford area or in any other SMJ l ine station. The launch of the service drew a large gathering of contemporary railway enthusiasts many of who can be seen in the photographs that have been well published over the years. Some cine films of the vehicle have survived and at least one copy is held in the archive collection administered by Rob Foxon of Leicester.

One Ro-Railer story that has recently surfaced was that it was alleged to have been sent out to substitute for an unavailable loco and coach on the Stratford - Broom Junction scheduled service one day. The turntable at Broom was unavailable (the East to West connection forming a triangle was 10 years in the future) so the Ro-Railer returned backwards!