The Abbots Ripton rail disaster occurred on 21 January 1876 at Abbots Ripton, then in the county of Huntingdonshire, England, on the Great Northern Railway main line, previously thought to be exemplary for railway safety. In the accident, the Special Scotch Express train from Edinburgh to London was involved in a collision, during a blizzard, with a coal train. An express travelling in the other direction then ran into the wreckage. The initial accident was caused by:
The accident (and the subsequent inquiry into it) led to fundamental changes in British railway signalling practice.
Overview
A coal train preceding the Flying Scotsman on the main East Coast up (south-bound) line was normally scheduled to be shunted into a siding at Abbots Ripton to allow the much faster Scotsman to pass. Because of a very bad snowstorm, both the coal train and the Flying Scotsman were running late and the signalman at Holme, the next station north of Abbots Ripton, judged that the coal train needed to go into sidings at Holme if it was not to delay the Flying Scotsman. He therefore set his signal levers to danger so as to stop the coal train, but it continued on the main line until it reached Abbots Ripton, where as expected the signalman waved it on to his box with a hand lamp, and directed it to shunt. The goods train had nearly completed shunting into the Abbots Ripton siding when the Scotch express ran into it at speed. The wreckage obstructed the down (northbound) line and a second collision occurred some minutes later when a northbound express to Leeds crashed into the wreckage. Thirteen passengers died in the collisions, and 53 passengers and 6 traincrew members were injured. Among the deaths was Dion William Boucicault, the eldest son of the prominent Irish-born actor-playwright Dion Boucicault.
The Great Northern was operating on the block system, which was supposed to eliminate such accidents, so the accident caused considerable alarm. It was soon established that the main problem was with signals and snow:
- the weight of snow on the semaphore arm and/or snow and ice on the wires by which the arm should be moved had meant that when signalmen had put levers to the 'danger' position from the normal 'all clear' the signals did not fully move to 'danger'
- in normal conditions, signalmen could see the signals they were controlling – in a snowstorm they could not
The coal train had therefore seen nothing to make it stop at Holme, and the Flying Scotsman whilst catching up with it had run through a number of signals which were showing 'clear' although their levers had been set to 'danger'.
Narrative
Great Northern Railway equipment and practices
Geography
Abbots Ripton is about 4.5 miles (7.2 km) north of Huntingdon (and 12.8 miles (20.6 km) south of Peterborough) on the East Coast Main Line, which handled both fast passenger trains and slow goods (largely coal) traffic. North of Peterborough passenger and coal traffic took different routes. South of Peterborough, they shared the same route; this was twin track in 1876, but stations with 'shunting sidings' were provided at frequent intervals to avoid slow goods trains, typically travelling at 20 mph (32 km/h), obstructing fast trains such as the prestigious 'Scotch express', which averaged 45 mph (72 km/h) (hence its unofficial nickname The Flying Scotsman), A slow train being caught up by a faster one would stop at such a station and reverse into the shunting siding, taking about four minutes to clear the main line. After the fast train had passed, the slow train would resume its journey. Abbots Ripton station had a shunting siding; for a south-bound ('up') train the previous siding was 5.8 miles (9.3 km) further north at Holme, 7 miles (11 km) south of Peterborough.
Block working
Traffic along the line was regulated by block working. Abbots Ripton and Holme had signal boxes and between them were two intermediate boxes. All controlled 'home' signals near the box and 'distant' signals about half a mile (c. 800 m (2,600 ft)) before the home signals. The line was thus divided into three blocks, each roughly 2 miles (3.2 kilometres) long; entry to each block was controlled by the signal box at the start of the block. Shunting into the siding at Abbots Ripton took place in a fourth block. The 'home' signals at Abbots Ripton were interlocked with the siding points, so that whenever the points were open to the main line the Abbots Ripton home signal lever had to be at 'danger'.
All boxes could communicate with adjacent boxes by their block telegraph. Signals were normally kept at 'all clear' but were set to 'danger' to protect trains as follows. When a train entered a block by passing a home signal, the signalman would set the home signal to 'danger', thus preventing a following train entering the same block. The distant would also be set to 'danger'. Trains were required to stop at a home signal at 'danger', but were allowed to pass a distant signal at 'danger' as this merely warned an approaching driver to moderate his speed to be ready to stop the train at the home signal. Both signals would be returned to 'all clear' when the next box telegraphed 'line clear'. Normally, as soon as a train was past a box's home signal, the signalman would telegraph 'line clear' to the preceding box. During foggy or snowy weather, however, when a train stopped at a station 'line clear' was not sent until the train had restarted, or been shunted into a siding. In good weather therefore a goods train being shunted into a siding at Abbots Ripton should have been protected against another train running into it by the Abbots Ripton 'home' and 'distant' signals; in falling snow, the home and distant signals of the previous box should have given further protection and the fast train should always have been at least one full block away.
Signal boxes serving stations/sidings had, as well as the block telegraph, 'speaking telegraph' instruments. These were not telephones, but Morse code senders, used for messages (for example how late a train was running).
Signals
On the Great Northern Railway, the signals used in conjunction with the block system were lower quadrant semaphores. They were connected to a lever in the signal box by a wire under tension, which passed over intermediate pulleys to a counterweighted arm on a signal post.
To set a signal to "all clear", the signalman pulled the appropriate lever in his signal box, which caused the wire to pull the signal arm down and into a slot on the signal post, against the force of a counterweight. When the lever was moved to set the signal to "danger", it did not positively elevate the signal to the horizontal danger position, but caused the wire to become slack, allowing the counterweight to raise the arm to the horizontal position.
During the day, the signal arms were normally visible from the signal box from which they were worked, so the system had no repeater in the signal box to confirm that a signal was actually showing the aspect corresponding to the position of the lever.
In an emergency, the signal could be set to "danger" by cutting the wire, but a heavy weight lying on the wire might pull on it, incorrectly keeping the signal at "all clear". Since the signals were normally set at "all clear", anything which stopped the arm moving out of the slot in the signal post would lead to the signal incorrectly indicating "all clear".
At night, or in poor visibility, an oil lamp displayed a white light when the signal was at "all clear" When the signal arm was raised to the horizontal “danger” position, a red lens was moved in front of the light, so that a red light was displayed to oncoming trains. Also in poor visibility, GNR regulations called for warning detonators to be laid, if possible, on the track at the home signal when it was set to danger. At stations where platelayers were available, detonators were also to be placed on the track at distant signals.
Brakes
The express trains were made up of non-bogie non-corridor four- or six-wheel carriages. There were 13 on the Leeds express, giving a weight (including the engine and tender) of somewhat over 200 tons. At this period, other railways often had to resort to using more than one engine to maintain a high top speed; the Great Northern (favoured with the Stirling 8-foot singles) prided itself on not doing so. As with all the other railways, though, it had considerable difficulties in stopping the trains rapidly once they were at speed. To stop a train, the driver could shut off steam, get his fireman to apply a handbrake on the tender and put the engine into reverse. He had no means of applying brakes to the rest of the train; indeed most of the carriages had no brakes. Two or three of the carriages were brake carriages with handbrakes, each with a guard who would apply them when (and if) he heard the driver "whistle for brakes".
In trials carried out after the accident under favourable conditions this was shown to bring the train to rest within 800–1,150 yards (2,400–3,450 feet) when travelling at 40–45 mph (64–72 km/h). The Railway Inspectors considered that much shorter stopping distances would be possible if passenger trains were provided with continuous brakes operable by the driver, and had urged such systems be fitted. This had been resisted by the railway companies as unnecessary, unreliable, expensive and dangerous.
Flying Scotsman
On the night of the accident, the Scotch express had 10 passenger carriages. These were first- or second-class; as customary the train did not carry third-class passengers. Notable passengers included the Russian Ambassador, the deputy chairman and another director of the Great Northern, and a director (John Cleghorn, formerly company secretary) and the chief engineer (Thomas Elliot Harrison, a past president of the Institution of Civil Engineers) of the North Eastern Railway. At the inquest, the coroner's summing up noted that it was a heavy responsibility to stop a train, but did not explicitly suggest the prestige of the Scotch express aggravated the responsibility.
The first collision
On the afternoon of 21 January, the Peterborough–Huntingdon area was experiencing a very bad snow storm; more than one witness at the Inquiry said they had never known worse: "freezing blowing and snowing ... bad for seeing signals". Crucially, the snow/sleet fell onto already cold ground and equipment, freezing on them.
The southbound coal train had left Peterborough about 18 minutes late, and therefore with about 12 minutes less lead on the Flying Scotsman than normal. It progressed steadily to Abbots Ripton where it stopped by the signalbox (at about 6.41) and on the instructions of the Abbots Ripton signalman began to shunt into the siding, as normal, to let the Flying Scotsman overtake. The signalman urged the driver to hurry up, as he was "keeping the Scotchman standing at Wood Walton [the previous signal box]".
The signalman at Holme had been concerned that, because the coal train was so late, if it went on to Abbots Ripton before shunting into a siding the Flying Scotsman would be delayed. To avoid this, he had decided to stop the train at Holme and put it into a siding there. He set his signal levers to put his signals to danger, but when the coal train arrived at Holme at 6.21 pm it did not stop. He telegraphed to Abbots Ripton that the train had run past the signals, and told the stationmaster at Holme that the train had disobeyed the signals. As the Inquiry report noted "The evidence as to what then happened at the Holme station was unsatisfactorily given, and is not clear".
The Holme station master told the enquiry that he then sent for the platelayers; whilst waiting for them he checked the up line home signal and saw it to be at 'danger'. However, when a down express went through he noticed that one of the signals did not go to 'danger' after it had passed. This appeared considerably at variance with other testimony.