[4][5][6] The LNER introduced The Coronation express service in July 1937, which ran between King's Cross and Edinburgh, calling only at York (southbound trains also called at Newcastle), so it was necessary for the A4 Pacific locomotive to pick up plenty of water at water troughs in order to avoid unscheduled stops.

It was arranged that on 8 October 1937, both the northbound and southbound Coronation trains would carry a railway inspector on the footplate in order to observe the water pick-ups.

4491 Commonwealth of Australia) had lowered their scoop to its limit, which when the water filled the tender, was unable to be retracted because of the force holding it there.

4492 Dominion of New Zealand) causing widespread damage, but critically, it forced out the glass from the locomotive's windows.

Several measures were taken in order to avoid a recurrence: a 60 mph (97 km/h) speed restriction was imposed on the Coronation service at Wiske Moor troughs; the tenders were modified so that any overflow was carried down through pipes, and armoured glass was fitted instead of Triplex toughened glass.