Britain’s first full scale rail crash test in more than 20 years drew stakeholders from across the rail industry to the Motorail Logistics site at Long Marston, where vehicle engineering specialist MIRA performed a live impact demonstration on 14 May. The event showcased technology transfer opportunities between road and rail ahead of new EU safety regulations targeting the crashworthiness of modern trains.
|Cutaway after impact. Click to enlarge.|
The high-energy collision mimicked an impact scenario set out in the European Standard for crashworthiness (EN15227). Propelled by a heritage DMU travelling at 22 mph (35 km/h), the test pitched a 32 tonne Mk 2 coach into a stationary class 86 locomotive, weighing in at 82 tonnes. During the impact, around 1.5 megajoules of energy dissipated to provide 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 a faithful assessment of occupant kinematics. 50th percentile dummies are designed to represent the average (50%) male in both dimensions and weight and provide a realistic biofidelic response when seated. Each dummy weighs the precisely average 78.4 kg (173 lbs).
Accelerometers recorded the coach’s deceleration pulse at the moment of impact, while 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. 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 frontfacing passengers launched forward during impact. Broken limbs and head injuries were very likely, reinforcing how vital occupant protection is, even in relatively low speed collisions.
Externally, damage was at a minimum. Damage to the coach included a fractured buffer. The loco also had its buffers bent, but otherwise stood up the pounding well. Clear indication that the design did little to cushion the effects of the impact, passing high levels of deceleration directly to the occupants with devastating results; an issue the EU legislation aims to tackle head on.
Although a full-scale crash like this hasn’t been performed here in the UK for over 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. We’ve been crash testing since the early 1950’s and performed thousands of tests over the years, but never a entire loco and carriage, so we were all keen to examine impact zone and high speed film.—Joanne Gleave, MIRA’s Safety Development Manager
For the event, MIRA partnered with Motorail Logistics which operates an ideal, off-the-network site at Long Marston in Warwickshire. With 20 miles of track, around 1,000 rail vehicles are currently stored there awaiting maintenance and/or refurbishment in Motorail’s workshops. The two parties joined forces with help from The Rail Alliance, a national body providing a networking forum for member organizations, encouraging collaboration and innovation.