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The Moorgate tube crash occurred at 8.46am on February 28, 1975 in London, England. A southbound Northern Line tube train crashed into the tunnel end beyond the platform at Moorgate station. Forty-three people were killed at the scene and several more subsequently died from severe injuries, in what was the greatest loss of life on the Underground in peacetime. The cause of the incident was never conclusively determined.

The crash had two further consequences affecting London Underground. Firstly, the southern end of the Northern City Line platforms (where the crash happened) was extensively rebuilt. Secondly, automatic systems for stopping trains at dead-ends was introduced into all dead-ends on the tube, regardless of whether the driver gives instruction to halt a train. These systems are known as Moorgate control.

Details of the incident

The train was on the 8:39am run on the Northern City Line service, a short, 7-minute journey from Drayton Park to Moorgate, terminating at platform nine of Moorgate station. At that time, plans were already afoot for the service, previously known as the Great Northern & City, to be transferred to British Rail (it is now operated by First Capital Connect).

Instead of stopping on arrival, the train appeared to accelerate, taking the crossover at about 35 mph (56 km/h). At the end of the platform was a 66 ft (20 m) long overrun tunnel with a red stop-lamp, then a sand drag, and finally a single hydraulic buffer in front of a brick wall. The sand drag slowed the train but it smashed into the buffer at about 40 mph and then into the wall. The first emergency call was received at 08.53am.

The incident would have not been so bad had the train been in a tube-sized tunnel, but the overrun tunnel was originally built to house mainline units and was 16 ft (4.9 m) high. The smaller diameter of the tube train meant that the second car in the set rode up above the trailing end of the driving car, and landed on top of it. The third car also split apart lengthwise and rode over the end of the second car. The driving car suffered the most damage, buckling at two points into a V shape, crushed between the wall and the weight of the rest of its train piling up behind it.

Investigation into the cause

The cause of the crash was never satisfactorily determined. The 56 year old driver, Leslie Newson, had worked for London Underground since 1969, had been in good health and took no alcohol or drugs. Police investigation showed that he had no reason to be suicidal and in fact had £300 in his pocket, which he was intending to use to buy a car for his daughter after the end of his shift.

When investigated, Newson was shown to have still been holding the dead man's handle, a device that immediately applies the brakes when released. Not only had he not even put his hands up to protect his face from the impact, but he had actually increased the speed of the train.

The autopsy found no evidence of a medical problem such as a stroke or heart attack that could have incapacitated Newson; he did not appear to have taken alcohol, although post mortem testing for this was hampered by the 4½ days it took to retrieve his body from the wreckage. It has been suggested on a TV documentary that Newson was in fact temporarily paralysed by a rare kind of brain seizure; on the other hand, railway writer Piers Connor, himself a former driver who knew Newson slightly, has suggested that his attention simply wandered from his driving at exactly the wrong moment. And of course suicide, while unlikely, cannot be ruled out.

Moorgate Control

As already stated, the accident lead to the introduction of automatic controls to prevent the incident occurring again. The system (known as Moorgate Control) was to be introduced on all dead end tunnels throughout the underground system. It was also installed on the main line trains that use the Moorgate platforms that used to be operated as part of the Northern Line.

Moorgate control consisted of a pair of standard train stop units, of the type used to halt trains that pass red signals. One was installed at the entry to the station platform and one about half way along the platform. The train stops are normally in the raised position. As a train approaches, it moves onto a section of track that initiates a time delay. At the conclusion of the delay, the train stop is lowered allowing the train to pass. The time delay is such that if any train is travelling at more than 10 mph (16 km/h) its tripcock will hit the train stop before it lowers. This exhausts the air from the braking system applying the emergency brakes. Both train stops have to be lowered to allow the train to leave the station.

In the originally proposed scheme, the train stops were augmented by a resistor in the traction current supply that was intended to prevent the driver from accelerating once he had passed either (or both) train stops. The resistor even made it through to the first trial of the system. The first run of the trial (the re-acceleration test) was initially heralded as a success as the driver indeed could not accelerate. One can only guess as to the change of mood, when it was discovered that the train was trapped in the trial siding unable to leave. The resistor was, of course, dropped from the final scheme.

Consequences for Mainline Railways

As is often the case, when these events happen the effects extend beyond the original company affected. British Rail became concerned at the possibility of a similar event happening at a terminus. An early consequence was to change the signalling system so that a colour light signal would not show green on approach to a dead-end terminus. This effectively regarded the fixed stop light at the buffers as part of the signalling system and required an appropriate 'caution' aspect to be displayed at the preceding signals. The displaying of a caution aspect would in turn cause the AWS horn to be sounded if AWS was fitted. This had to be acknowledged or the train brakes would be automatically applied. The eventual adoption of slow speed control when appoaching dead-end platforms as part of TPWS can be traced back to the Moorgate tube crash.

External links

• BBC News account of the 1975 crash
• The Railways Archive web site has a scanned copy of the official accident report in PDF. This direct link seems to work sometimes.

See also

• Croome, D. & Jackson, A. Rails Through The Clay — A History Of London's Tube Railways (2nd. ed. 1993), London, Capital Transport Publishing.

• British railway accidents
• History of London
• London Underground