“The sole purpose of RAIB investigations is to prevent future accidents and improve railway safety,” the Rail Accident Investigation Branch reminds as it publishes its findings into last year’s Audenshaw derailment. The 83‑page report, released on 24 December 2025, lays out how a routine freight movement turned into an eight‑week closure in Tameside.

At about 11:25 on 6 September 2024, nine of the train’s 24 fully laden wagons left the rails on a small bridge carrying the railway over a public footpath in Audenshaw, Greater Manchester. Nobody was injured, but the track, bridge and several wagons were badly damaged and repairs kept the route shut for around two months.

Investigators say the track gauge spread as restraint between the rails was lost, allowing right‑hand wheels to drop into a widening gap. This bridge used a longitudinal bearer system-rails fixed to timber bearers via baseplates and screws-rather than conventional sleepers and ballast.

RAIB’s metallurgical work found fatigue failures in screws securing the baseplates to the timber bearers. Some had already failed before the train arrived, with evidence of previous screw failures at the same spots. Records confirm at least three earlier failures, including one before 2020, but many required documents were missing.

Vehicle dynamics analysis showed the screws, in this configuration, were never expected to achieve endless fatigue life-even though train forces were below the limits in Network Rail standards. Installed in 2007, the bearer system then faced busier traffic from 2015 onwards, accelerating wear on the fixings.

Inspections didn’t spot the danger. RAIB found both automated and manual regimes could not reliably detect failing or failed screws. Regular dynamic track geometry readings sat within permitted limits, so no intervention was triggered. Staff managing the asset did not fully appreciate the significance of previous screw failures.

Two deeper problems are highlighted. Network Rail lacked effective processes for managing longitudinal bearer systems-covering design assurance, installation, inspection and maintenance. And the local track team failed to record and report screw failures, a gap that went unchallenged by Network Rail’s assurance regime over several years.

Eight actions are set for Network Rail: tougher component assurance; clearer guidance for design, installation, maintenance and failure reporting; stronger staff competence; closer working between track and structures teams; better understanding of how the supporting structure affects track behaviour; a review of how traffic changes alter risk and the response needed; complete records of LBS assets; and tighter internal assurance so inspections and maintenance are properly documented.

For Greater Manchester, where rail freight keeps factories, warehouses and ports supplied as much as it carries commuters, the lesson is plain: oversight outside the capital must be watertight. An eight‑week shutdown on a short span in Tameside carries real costs for local firms and communities.

RAIB stresses it does not apportion blame; its role is prevention. A short video summary accompanies the report. Network Rail is expected to respond to the recommendations. The Northern Ledger will track what changes are delivered on this bridge and across the North.