Collision course

Britain’s first full-scale rail-crash test in more than 20 years has been performed by vehicle engineering specialists MIRA.

The demonstration at the Motorail Logistics site at Long Marston in Warwickshire was designed to test the crashworthiness of modern trains ahead of new EU rail safety regulations.

The high-energy collision mimicked an impact scenario set out in the European Standard for crashworthiness (EN15227). Propelled by a heritage DMU rail car travelling at 22mph, the test pitched a 32 tonne Mk 2 coach into a stationary class 86 locomotive, weighing 82 tonnes.

MIRA engineers determined that around 1.5 megajoules of energy dissipated during the impact. This, they said, gives a graphic demonstration of the devastating effects felt by rail passengers when collisions occur.

On board were four 50th-percentile Hybrid III crash test dummies to provide an assessment of occupant kinematics. The dummies are designed to represent the average male in both dimensions and weight - in this case, 78.4kg.

Accelerometers recorded the coach’s deceleration pulse at the moment of impact. An array of stills cameras and high-frame-rate digital video cameras recorded the crash dynamics as dummies and interior furnishings flew in all directions.

MIRA’s report of the event explained that dummies with their backs to the direction of travel would have suffered chest and abdominal injuries as they absorbed the weight of tabletops, ripped off by the front-facing passengers launched forward during impact. The result would have likely been broken limbs and head injuries. This, the report stresses, reinforces how vital occupant protection is, even in relatively low-speed collisions.

The external damage to the coach was at a minimum and included a fractured buffer and the loco had its buffers bent. The report said this indicates that the design did little to cushion the effects of the impact, passing high levels of deceleration directly to the occupants with devastating result. The EU legislation hopes to tackle this issue.

‘Although a full-scale crash such as this hasn’t been performed here in the UK for more than 20 years, automotive crash testing is a daily occurrence for us at MIRA, so we were confident the demonstration would run to script and right on cue,’ said Joanne Gleave, MIRA’s safety development manager. ‘We’ve been crash testing since the early 1950s and performed thousands of tests over the years, but never an entire loco and carriage, so we were all keen to examine the impact zone and high-speed film.’

For the event, MIRA partnered with Motorail Logistics, which operates from an off-the-network site at Long Marston in Warwickshire. The site, which has 20 miles of track, has approximately 1,000 rail vehicles stored there awaiting maintenance or refurbishment in Motorail’s workshops. MIRA and Motorail Logistics worked with the Rail Alliance, an organisation that encourages networking for collaborative and innovative projects.

‘This event clearly demonstrates that the facility here at Long Marston is a perfect venue for this sort of safety development and we look forward to playing our part in delivering safer rail travel to passengers throughout the UK and mainland Europe,’ said Colin Flack of the Rail Alliance.

‘MIRA provided a unique opportunity to witness first hand the energies involved when two substantial masses come together, dispelling any illusion that the UK lacks the ability to undertake full-scale crash tests. The stage is now set for the UK to act as the European test bed for safety development.’