Why no passenger airbag with only driver if a crash?

There's no point activating an airbag to protect a passenger that isn't there. They're designed to protect the occupants in a frontal collision, and are fairly expensive to replace.

edit: Yeah, what he said.

 

The passenger airbag will not deploy unless the passenger seat senses that the person weighs enough. It was found that children were sustaining injuries from the airbag instead of being protected by it. Everyone recommends that children ride in the back seat, but if they are riding in the front seat, it's better that the airbag not deploy.

 

<div class='quotetop'>QUOTE(8AA @ Sep 22 2007, 02:49 PM) [snapback]516287[/snapback]</div>

I agree totally with you. However, the Prius WILL deploy the front passenger airbag if a child is in the seat. Even a small bag of groceries will turn it on. So the Prius sensor system is faulty in this case, if that was the purpose of the sensors. I don't think they are there for that. I think they are there to just shut the airbag off if there is no passenger. A baby in a carrier may not be sensed, but it would be close.

The sensor system does do something good - it forces me to secure cargo on the floors and in the back, where it belongs.

 

<div class='quotetop'>QUOTE(Whidbey Island @ Sep 22 2007, 03:32 PM) [snapback]516275[/snapback]</div>

In short no, the passenger airbag is not beneficial to the driver. The airbags that we deploy in our lab fully inflate in 45 milliseconds and have started to deflate by 60 to 75 milliseconds. The passenger airbag will not be still inflated if the driver somehow was knocked out of position in a secondary impact. Passenger airbags also rip through instrument panel when they deploy. This destroys the instrument panel. The instrument panels that my company makes cost $2000 plus labor. Thats a lot of money to waste.

There is some confusion about airbags and specifically about the new dual-power airbags. The airbag will deploy if the passenger meets the minimum weight requirement for an airbag. Dual-power airbags do not deploy at different power or speed for different sized passengers. If the passenger is under the weight limit the airbag simply does not deploy.

 

<div class='quotetop'>QUOTE(Tideland Prius @ Sep 22 2007, 05:34 PM) [snapback]516333[/snapback]</div>

You are correct, one of the criteria the computer will use to decide how many stages to deploy is the speed of the crash. Some other criteria are seat position and seat belt use.

What I was trying to clear up is the misconception by the general public that dual-stage airbags will adjust for the weight of the passenger. Many people think that these airbags will deploy both stages if the passenger is heavy, such as a large male; but only deploy one stage if the passenger is light such as a small female. This is incorrect. Weight only determines if the bag deploys or not, it is not connected to the number of stages.

Also on a duel stage deployment the stages don't deploy at the same time. The second stage will deploy about 5 milliseconds after the first stage.

BTW, air bag deployments are cool to watch and VERY loud. You literally can't see the bag come out with the naked eye, suddenly it's just there, fully inflated.