Slip coach
A slip coach, slip carriage or slip portion in Britain and Ireland, also known as a flying switch in North America, is one or more carriages designed to be uncoupled from the rear of a moving train. The detached portion continued under its own momentum following the main train until slowed by its own guard using the brakes, bringing the slip to a stop, usually at the next station. The coach or coaches were thus said to be slipped from the train without it having to stop. This allowed the train to serve intermediate stations, without unduly delaying the main train.
Slip coaches as described above were mainly used in Britain and Ireland from 1858 until 1960; for most of this period there was serious competition between railway companies who strove to keep journey times as short as possible, avoiding intermediate stops wherever possible.
Competition increased as locomotives became bigger and able to haul heavier trains at faster speeds for longer distances, trains no longer need to stop so often, for fuel and water for themselves, using water troughs to fill up on the move, or for facility stops for passengers by providing corridor coaches, dining and sleeping carriages. Faster services were becoming progressively safer as more efficient continuous braking was fitted and the absolute block system installed on main lines. All these led to the use of slip services in some places where there was a financial advantage to the company to provide it.
Disadvantages
There were disadvantages to slip coaches. The slip portion was mostly isolated from the main train and its facilities such as a restaurant car; this didn't matter in the early days, for at that time it was not possible to move through a train from carriage to carriage. Gangway connections began to be used from 1882 and throughout a train by 1892, but most slip connections were not fitted with gangways, even if the rest of the train was. The LNWR seems to have been the only exception, using slips with gangways for a few months before the First World War.The slip service needed additional staff – at least one extra guard for the slip portion and possibly the use of a locomotive and its crew if the slip wasn't able to reach the platform; often the slip portion would be attached to another train or locomotive for an onward journey. While these additional staff requirements were lower than if an additional train had been provided, they were still substantial. If the weather was bad, usually because of snow or fog, it might not be possible for the slip to be safely effected, in which case the train usually halted to detach the coach.
Slip carriages were also confusing to some passengers: there are frequent reports of passengers who boarded the wrong carriage of a train and ended up at an unintended destination. This could occasionally lead to passengers causing trains to stop by using the emergency communication system.
Slip carriages are quiet: they are usually equipped with a horn to sound warnings to people near the track if there is time, but their silence has proven fatal, as in the case of a railway worker whose inquest returned a verdict of accidental death when he stepped into the way of a recently released slip at.
A few examples of slips being used in other countries will be found below. In some countries, such as India, the term slip coach refers to a coach that terminates its journey at a station prior to the final destination of the rest of the train. The coach or coaches are left behind after being detached from the train while it is stationary.
Slipped coaches were often also through coaches in that they often continued to another destination either by having a separate locomotive attached or by being attached to another train.
History
The earliest example of slipping occurred on the London and Greenwich Railway when it opened in February 1836 between and. There was limited space at the terminals; they consequently used a system known as fly-shunting. The system allowed the company to operate three trains with a single locomotive. There were two platforms at each end of the short, line, as a locomotive and its train approached the points before a terminus the driver would signal the guard who would detach the carriages from the locomotive and apply his brakes to slow down while the locomotive ran through the points to another waiting train, the points would be changed after the locomotive had passed and the carriages run into the platform under their own momentum and brakes. The locomotive and its new train then proceeded to the other terminus where the process would be repeated.Samuel Wilfred Haugton, the locomotive superintendent of the Dublin and Kingstown Railway following a visit to the L&GR in September 1849 took the technique back to Ireland, where following alterations to locomotives and installation of semi-automatic points, it remained in use for several years.
Another early example of slip services was on the Hayle Railway which started passenger operations in 1843. The company operated three daily mixed mineral and passenger trains with the passenger coaches at the rear of the train, and the practice approaching Hayle was to uncouple the passenger portion while the train was in motion, let the mineral train negotiate a set of points which were then switched allowing the passenger coaches to coast to the passenger station. These trains were still running in 1850 despite there having been a non-fatal accident in 1843.
The first certain example of slipping coaches off a moving passenger train was at on the London, Brighton and South Coast Railway in February 1858 when the 4 p.m. train from to which ran non-stop from to Brighton slipped a portion for and. The portions were connected with a patent coupling and the instructions to the staff made sure the side chains were not connected. The complete train was to slow as it approached Haywards Heath, the slip to be effected, and the slipped portion to slow itself to arrive gently at the station platform. Once the slipped portion had stopped at the platform the engine to haul it to Hastings was allowed to exit the siding where it had been waiting and attach itself to the front of the new train. The slipping was coordinated by a series of communication bell signals between the guards on the two portions of the train and the locomotive crew.
The Great Western Railway followed suit when on 29 November 1858, carriages were slipped at and off to Birmingham trains. The slip service being introduced in December 1858 with a slip at Banbury off the 9:30 a.m. from Paddington.
The South Eastern Railway was an early user of slip services: there is a possibility that it began this a month before the LB&SCR, in January 1858. That month's timetable contained details of the 4.25 p.m. from to that leaves...passengers at......:''train does not stop at Etchingham. There is a similar note regarding another train and : how the trains left passengers without stopping is not explained, but there is no corroborating evidence to indicate the use of a slip. The SER was using slip services in 1859 when the 12.20 p.m. to slipped a portion at.
The remaining British railway companies adopted slipping with varying degrees of enthusiasm, with 58 daily slips being made by nine companies in 1875, rising to 189 being made by 12 companies in 1914, when slipping was at its peak. During the First World War slip services almost disappeared, for there were fewer staff available to operate any service, and slip services needed an additional guard compared to the train stopping. After the war, slip services did not attract any priority; services were necessarily slower than normal because the railway suffered from a maintenance backlog, there was still a shortage of staff, and companies were uncertain what the future held after the railways had been under Government control during the war. In 1918 there were eight daily slip services; this had risen to 31 at the Grouping, and reached a post-war peak of 47 in 1924.
Slip services gradually fell out of favour, for many reasons. In the south-east the railways were electrified, allowing faster acceleration; elsewhere trains were travelling faster, and hence able to stop instead of using slipping coaches, yet without a later arrival time. Perhaps the most compelling reason, according to The Manchester Guardian'', was the lack of corridor connections to the rest of the train: slip-coach passengers could not access the restaurant car.
Early rope working slip
The London and Blackwall Railway in east London, England, opened in 1840, running from to. It operated as two independent side-by-side railways, each worked by stationary engines and a rope which was wound on and off large drums at each end of the line.The carriages would start off at four stations and the process was as follows:
- Five carriages connected together would leave Fenchurch Street, coasting using gravity to Minories, where they would be stopped.
- The five carriages, and a sixth one waiting here, were attached to the rope; concurrently single carriages would be attached at and.
- When all eight carriages were attached, and the confirmation telegraphed to the destination terminus, the rope would be started.
- As the rearmost carriage approached its destination the guard would release it, bringing the carriage to rest using his brakes. This happened at Stepney,, and, leaving the remaining four carriages to be released shortly before Blackwall, into which they coasted under their own impetus.
- The rope then stopped.
- The opposite then happened: four coaches were free-wheeled out of Blackwall; all eight coaches at the various stations were attached to the rope; a telegraph signal told the engine operator all was attached; and the rope wound in the opposite direction, slipping coaches at Stepney, Shadwell and Minories, at each of which one coach stopped; and five coasted into Fenchurch Street.