Another year, another airbag. In 2009, Ford introduced inflatable seatbelts; four months later, Toyota debuted a Scion iQ with airbags for the seat bottoms and rear window. In late 2012, GM announced the industry's first airbag between the front seats, and Volvo followed six months later with the world's first pedestrian airbag in the not-for-America V40.
Ford, it seems, has restarted the cycle. The automaker says the redesigned 2015 Mustang will debut an active glove box — a trick glove-compartment door that uses an embedded airbag that pops forward and acts as a knee blocker for the front passenger. It joins seven other standard airbags on the Mustang coupe, including a conventional driver knee airbag.
So, uh, why didn't Ford go with a conventional passenger knee airbag?
Space and weight, the automaker says. Knee airbags have to inflate downward and forward. They also have to absorb a concentrated impact from your knees. The active glove box uses an airbag to spring the glove-compartment door forward, and the panel acts as a knee cushion that distributes the impact across a wider area than a conventional airbag.
All of it requires less inflation pressure, so Ford says the inflator is 65 percent lighter and 75 percent smaller than a conventional fabric knee airbag. The active glove box's hidden airbag isn't even fabric; it's an inflatable plastic bladder that's sandwiched between the inner and outer panels of the glove-compartment door.
"This bladder is part of the glove-box door inner [panels] and the door outer [panels]," Ford safety spokesman Ed Signs said. "It's the same plastic that your glove-box door outer would normally be made of, and in the context of the forces that we're talking about, it's relatively pliant."
That means it's more of a springboard than a rigid surface against your knees. Since it only pops the door forward, it doesn't affect any space inside the glove compartment, Signs added.
Ford says all of it allows the glove compartment to sit farther forward, increasing passenger space in the 2015 Mustang. The automaker said in a press release that the active glove box provides protection similar to a conventional knee airbag, but we won't know until the car gets crash-tested by a third party.
"Automakers are coming up with a lot of innovative airbag designs that could protect people better in crashes," Russ Rader, spokesman for the Insurance Institute for Highway Safety, told us. "We won't know more until we test a vehicle with this type of airbag."
Airbags can improve crash tests, but the results matter most. Rader told us in 2011 that knee airbags had yet to prove their worth, and a number of cars without them score very well in IIHS' latest tests.
But new technology is always welcome, especially on the safety front. The new Mustang arrives this fall; the coupe starts at $24,425, including destination.