The RAIB have published a safety digest on this incident from November 2019 where a group of track workers had to jump clear of a Virgin Trains service approaching at 125mph with less than a second to spare:
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Drilling into it it appears that the lookout to the north and the LOWS controller did not come to a clear understanding:
So we have another incident where only good luck and quick reactions prevented a horrible accident with a number of track workers killed following on from the horrific accident in South Wales and other near misses around the country. This one also comes with a flavour of incident at Balham (which occurred before this in April 2019 and had a report published in February 2020) where safety critical communication was not up to standard and contributed to a serious near miss.
At around 09:00 hrs on Thursday 14 November, three members of Network Rail staff had to jump clear of a train travelling at a speed of 125 mph (200 km/h) near Kirtlebridge, Dumfries and Galloway. The staff had just begun a track inspection under the protection of the radio-based Lookout Operated Warning System (LOWS) when the train approached unexpectedly round a bend. The train driver sounded the horn and applied the emergency brake. The staff jumped clear less than one second before the train passed. There were no injuries.
The LOWS equipment they were using at the site of work comprised a receiver unit equipped with flashing lights and a siren intended to warn staff working nearby when a train is approaching. The lights and siren start operating when switches are operated on one or more transmitter units connected to the receiver unit by a secure radio link. A person designated as the LOWS controller remains with the receiver unit while each transmitter unit is operated by a LOWS lookout. The controller and each lookout carry a dedicated mobile phone, provided with the LOWS equipment, to communicate while using the equipment. LOWS is regularly used on the West Coast Main Line in southern Scotland because the combination of high train speeds and curved track often precludes use of a warning system relying on lookouts using flags.
The incident occurred at Merkland, 3.2 km south of Kirtlebridge emergency crossovers, while staff were inspecting the track. The site team comprised nine members of Network Rail staff including a Controller of Site Safety (COSS), LOWS controller and two LOWS lookouts. The system of work required one of the LOWS lookouts to be positioned 1.8 km north of the site of work and the other to be positioned 2.5 km south of the site. The LOWS team were all experienced users of this equipment and had worked in this area on many previous occasions.
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Link
Drilling into it it appears that the lookout to the north and the LOWS controller did not come to a clear understanding:
There is conflicting evidence about the words spoken during the conversation at 08:58 hrs during which lookout (north) and the controller reached a different understanding about whether the lookout duties had already commenced. The controller stated he said “right, that’s you up and running”. The lookout states the controller told him he was going to phone the other lookout and thought the controller was then going to phone him back.
Witness evidence shows that members of the LOWS team were following their normal practice of using informal language, rather than the formal communication protocol mandated by Network Rail. It is certain that their conversation did not result in a clear understanding between the staff involved and it is likely that use of the formal words “you are now looking out” would have resulted in lookout (north) appreciating that the LOWS controller was expecting him to be sending warnings when the incident occurred.
The lookout also stated that he would normally start sending warnings after the system was tested and without a further phone conversation. This is the process described in the LOWS training but, on this occasion, he left the conversation thinking he would be called back.
So we have another incident where only good luck and quick reactions prevented a horrible accident with a number of track workers killed following on from the horrific accident in South Wales and other near misses around the country. This one also comes with a flavour of incident at Balham (which occurred before this in April 2019 and had a report published in February 2020) where safety critical communication was not up to standard and contributed to a serious near miss.