SOUTHERN California Regional Rail Authority is planning to replace its 42 Metrolink push-pull driving trailers with new cars, following a number of collisions with road vehicles on level crossings, one of which killed 11 people in January 2005.

Part of an order for 80 to 100 cars likely to be placed this month, the new driving trailers will be designed to spread collision impact forces along the train. The design was still being developed in December, but FRA approval is expected early in 2006.

Five test collisions have already been staged, the most successful of which caused severe damage to just the first 0·9m of a car compared to 6·1m of a conventional coach. Structural improvements include stronger end elements and energy-absorbing zones outside the passenger compartments, while interior fittings and tables may also be redesigned. The cost of these measures may reach $500000 per car. Older driving trailers will be converted into standard coaches.

The order may include an option for 59 more cars to expand Metrolink services using funding from Orange County Transportation Authority, and a further option for southern Florida's Tri-Rail.