First, airbags protected drivers in frontal crashes. Then they protected bodies hit from the side. Now BMW will add side-impact protection for the head.
BMW will offer its Head Protection System - an inflatable tube that stretches diagonally across the window - on the 5 series and the 7 series for 1998.
The 7 series goes on sale in the US in July and in Europe a couple of weeks later. The system will be an option in Europe, priced at about $330, said Thomas Zauber, a spokesman for BMW of North America Inc. It will be standard in the US.
Head injuries are a major concern in side impacts. The National Highway Traffic Safety Administration in the US says that in a side impact, 50 percent of all occupants are injured, and almost half of those injured have head injuries.
BMW said two years ago it would use the new safety system. The heart of the system is a plastic tube 1.5 meters long stored beneath the A-pillar trim and the edge of the headliner.
The head protection system is offered in conjunction with side-impact airbags in the doors.
BMW may make offer the head-impact system on the next-generation 3 series, Zauber said. Side-impact airbags are a $385 option on 1997 3 series sedans and coupes in the US. The new 3 series is scheduled to be introduced in 1998.
BMW may also install the Head Protection System for rear-seat passengers, Zauber said. But engineers have not determined how to mount the forward anchor of the rear system so it does not interfere with the front head restraint.
The system was developed in the US by Simula Inc. of Phoenix, using crash technology it originally developed to protect military helicopter pilots, said Robert Messenger, Simula's business development manager. The inflator is supplied by Autoliv GmbH, the Swedish supplier of seat belt and airbag systems.
Simula will assemble the restraint at a facility in Arizona and ship it to Germany for installation, Messenger said.
Although BMW is scheduled to be first to market, other suppliers are working on inflatable head-protection systems. Some systems are incorporated into the side airbag that protects the thorax.
Competitors include TRW Inc., General Motors' Delphi Automotive Systems, and Autoliv, which has been working with Mercedes-Benz to develop a side curtain restraint that would deploy from the edge of the headliner and cover both front and rear windows.
Within a year after BMW's launch, another automaker will begin using the same system, Messenger said. He would not identify the automaker, but he said Simula has not yet sold its system to any of the US-based automakers.
Because the Head Protection System is anchored to the vehicle body, the separate system provides better protection than a combination head/thorax bag, Messenger said. With a combination bag, the person's head pushes and moves the bag, he said, but the BMW system restrains a person's head and becomes a structural member of the vehicle.
Cost is an issue
BMW and Simula would not reveal the cost of the Head Protection System. But the system is more expensive than a combination side-impact airbag, said an industry source. A combination side airbag costs about the same as a front-impact airbag.
Several automakers are debating whether the tube system provides more protection than a combination bag to justify the price, the source said.
BMW is taking pains not to call the restraint an airbag, partly in response to concerns raised about deaths and injuries caused by front-impact airbags.
When the tube inflates, it pulls down from the headliner rather than blowing out toward the driver or passenger, Zauber said. And unlike an airbag, which inflates and deflates quickly, the Head Protection System remains fully inflated.