SEPTA is replacing its oldest train cars, the Silverliner II and III, with new Silverliner V cars from the Hyundai-Rotem Corp. assembly plant in South Philly.

The Silverliner V cars have a trapdoor mechanism similar to the Silverliner IV cars, which remain in service. But on the Silverliner V, the latch that pops the door is under a divider, which SEPTA officials expect to reduce the chance of someone triggering it by accident.

SEPTA's chief counsel, James Jordan, said the Silverliner V cars have not been in service long enough to know if trapdoor claims are less frequent than on the earlier Silverliners.

-William Bender