A second iteration of the door is planned and may include some design improvements. This next version will be tested as before, minus the destructive aspect. Once complete, the door will go into use on a train to gauge the response of the composite to the subway environment.

As for the all-important goal of reducing the weight, the thermoplastic door is about half the weight of existing metallic ones. Each subway car has multiple double doors, so these reductions in mass add up, particularly when lighter motorsrakes and other follow-on factors are considered.

The thermoplastic subway door demonstration has garnered attention – and prizes. The design won the U.K.’s National Rail Awards Stephenson Award for Engineering Innovation.

“The design has proven that is worth continuing with,” Ive says. “Following further verification of proof of concept it will be worth investing in the tooling and ancillary equipment to mass produce these doors.”