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Very impressive that they do that level of testing.

I guess now a debate is, should that airbag have gone off when it landed? How does the driver steer and maintain control afterwards? It seems the airbag would further disorientate the driver.

I've read some airbags are now triggered by accelerometers (or whatever they're called). So now it's possible for airbags in theory to go off even if nothing is crumpling at the front.
 

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No I wasn't. You really think the airbag needed to go off? I don't know the answer, that's why I was asking the question. It seems to me, 'maybe' it didn't really need to go off.

I kind of always assumed the airbag would go off only after a serious enough impact that for all practical purposes would leave the vehicle not drivable and it's going off to save the driver as expected since there's nothing really left for the driver to do.

This is a case where it went off, but the vehicle 'appears' to still be 100% drivable and maybe in some other scenario rolling towards a tree, another obstacle, oncoming traffic, or a pedestrian such that a driver that hasn't had the airbag go off in their face stunning them could then have potentially avoided. Many times, it's the secondary accident that kills.

I've seen really serious rear endings where both cars had damage and yet the air bags did not go off . Seems weird that it did go off in this case and yet, the forces don't appear to have done any serious damage to the front of the car that we can see.

Lots of people get injured from the airbags themselves. What's the greater risk in the above video? Not having it go off, or having it go off and risking injuries from the bag itself?
 

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Patty, the test is conducted at 50 mph. After going completely airborne, the car hits the ground head-first at a speed of maybe 45 mph. If the airbag didn't deploy, the driver's head would hit the steering wheel with sufficient force to cause major injuries and he would be in no position to control the car. In my opinion, the driver would be merely along for the ride once the car hit the ditch.
 

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The car did not hit the ground head first. It hit it at what, 30 degrees? 50mph was the horizontal speed entering the ditch. The vertical component of the speed when hitting the ground is unknown. I find it hard to believe that the impact with the ground was the equivalent of a 45mph head on impact into a solid barrier. The dynamics in this case are completely different. The car readily kept rolling and moving forward DURING the actual impact of landing. It didn't even seem like it slowed down. Watch the video again. On top of that, the air bags didn't go off until after the front wheels had fully compressed up some distance past the point of initial landing. I would guess the actual impact is closer to 5-10mph.
 

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These crash tests with the child seats in the second row are a huge marketing weapon for Volvo .........I don't believe I've seen crash test involving child seats from other brands before, at least not this prevalent
 

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Discussion Starter #9
These crash tests with the child seats in the second row are a huge marketing weapon for Volvo .........I don't believe I've seen crash test involving child seats from other brands before, at least not this prevalent
There was an interesting article about this crash test on a professional automotive engineering newswire this week saying how impressive this work is and yet Volvo isn't using it in adverts or making noise about the sort of work they do. The author concluded (Im paraphrasing) "Volvo doesn't should about this but quietly works away in Sweden making superbly engineered cars with industry leading safety kit and performance"

Im all for humility but Volvo ought to make more of there excellent work above and beyond the few mandated crash tests and their performance.

The NHTSA small overlap test is such an example. Not a mandated test. Volvo excels even with a 12 year old design XC90. Other brands had serious failings.

Inviting journalists to witness this crash test is a good start but Volvo really ought to make this more widely available. In the very least some coverage in the brochures!!
 

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Discussion Starter #10
corrected spelling

"There was an interesting article about this crash test on a professional automotive engineering newswire this week saying how impressive this work is and yet Volvo isn't using it in adverts or making noise about the sort of work they do. The author concluded (Im paraphrasing) "Volvo doesn't shout about this but quietly works away in Sweden making superbly engineered cars with industry leading safety kit and performance"

Im all for humility but Volvo ought to make more of there excellent work above and beyond the few mandated crash tests and their performance.

The NHTSA small overlap test is such an example. Not a mandated test. Volvo excels even with a 12 year old design XC90. Other brands had serious failings.

Inviting journalists to witness this crash test is a good start but Volvo really ought to make this more widely available. In the very least some coverage in the brochures!!
 

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Dummy's head strikes airbag at ~0.35 sec. You can see it more clearly in the YouTube version when played full-screen at slow speed. Case closed.
So what? If the airbag went off everytime somebody stood on their brakes, or even in 2mph accidents, they would also make contact with the airbag. Just because contact is made, doesn't mean the airbag was really needed.

Heck, it looks like when the Volvo first hits the end of the ditch at 50mph that the driver is thrown forward and the airbag didn't go off at that point, but I'm sure if it had, the driver would have made contact with it. Some speed is lost there and other is translated into vertical speed. When it lands, what is it going? 40-45? And as it's rolling away after landing, 30-35? That's why I guess 5-10mph impact.

You're missing my point. If you think that an airbag going off is always the best possible thing, then you need to google the injuries that people incur from airbags going off.

There are threshold accidents that happen at the very lowest range of what triggers an airbag, and people many times get more hurt from the airbag than if it had just not gone off. I'm sure if airbags could benefit from hindsight, there would be many cases where they would change their mind and not to go off. But obviously that doesn't exist.

Fortunately Volvo is not using the same air bag supplier as Honda and the dummy's head is not full of metal shrapnel.

My daughters high school friend was in a rear ending a few weeks ago sitting in the passenger seat of her boyfriends car that rear ended somebody. I happened to be riding my bike by right after it happened. The damage wasn't really severe. She was wearing her seatbelt but still ended up in the hospital with a neck brace and lost two front teeth and has undergone some surgeries. "Maybe" if it had not gone off she would only be bruised and sore from the seatbelt? Of course, all hypothetical and we'll never really know.

I can't help it, the engineer in me notices things and I like to ask questions.

You are glad it went off, I have a big question mark and will probably never know the 'real' answer.
 

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So what? If the airbag went off everytime somebody stood on their brakes, or even in 2mph accidents, they would also make contact with the airbag. Just because contact is made, doesn't mean the airbag was really needed.

Heck, it looks like when the Volvo first hits the end of the ditch at 50mph that the driver is thrown forward and the airbag didn't go off at that point, but I'm sure if it had, the driver would have made contact with it. Some speed is lost there and other is translated into vertical speed. When it lands, what is it going? 40-45? And as it's rolling away after landing, 30-35? That's why I guess 5-10mph impact.

You're missing my point. If you think that an airbag going off is always the best possible thing, then you need to google the injuries that people incur from airbags going off.

There are threshold accidents that happen at the very lowest range of what triggers an airbag, and people many times get more hurt from the airbag than if it had just not gone off. I'm sure if airbags could benefit from hindsight, there would be many cases where they would change their mind and not to go off. But obviously that doesn't exist.

Fortunately Volvo is not using the same air bag supplier as Honda and the dummy's head is not full of metal shrapnel.

My daughters high school friend was in a rear ending a few weeks ago sitting in the passenger seat of her boyfriends car that rear ended somebody. I happened to be riding my bike by right after it happened. The damage wasn't really severe. She was wearing her seatbelt but still ended up in the hospital with a neck brace and lost two front teeth and has undergone some surgeries. "Maybe" if it had not gone off she would only be bruised and sore from the seatbelt? Of course, all hypothetical and we'll never really know.

I can't help it, the engineer in me notices things and I like to ask questions.

You are glad it went off, I have a big question mark and will probably never know the 'real' answer.
So basically youre saying you know better than the safety exprets at volvo...?!
 

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corrected spelling

"There was an interesting article about this crash test on a professional automotive engineering newswire this week saying how impressive this work is and yet Volvo isn't using it in adverts or making noise about the sort of work they do. The author concluded (Im paraphrasing) "Volvo doesn't shout about this but quietly works away in Sweden making superbly engineered cars with industry leading safety kit and performance"

Im all for humility but Volvo ought to make more of there excellent work above and beyond the few mandated crash tests and their performance.

The NHTSA small overlap test is such an example. Not a mandated test. Volvo excels even with a 12 year old design XC90. Other
brands had serious failings.

Inviting journalists to witness this crash test is a good start but Volvo really ought to make this more widely available. In the very least some coverage in the brochures!!
Yea I don't get it. Volvo should be running those till the cows come home.........MB runs those stupid auto derby ads all the time showing how safe the ML is. Whatever:p
 

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So basically youre saying you know better than the safety exprets at volvo...?!
No I'm not. I raised a question.

Volvo (and other manufacturers) are always changing things. When airbags first came out, they always went off, even in really slow accidents. If I'd asked the question back then, would I have gotten the same response from you and calhon? And now that the "safety experts" have learned more, they no longer always go off, now they have thresholds. Now they even have airbags that don't deploy at full force.

Volvo and other manufacturers have actually had recalls involving safety air bag timing.

What's to say that while they're better, they're still not perfect? So I asked a question.


Let's not forget Volvo also has "safety experts" regarding HMI interfaces and in one step, these experts have gone from an all button click wheel interface to an all touch. Me and others questioned the lack of a touch interface way back for complicated things, and typical swedespeed, "trust the safety experts that are looking out for you because touchscreens are distracting". LOL, now we've got all touch. What an about face. So much for the "experts".

Even experts change their minds or make mistakes. I'm not saying this is one of them. I just asked a question.
 

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No I'm not. I raised a question. ...
You did quite a bit more than that. Regardless, the question relates to the specific scenario shown in the video. The answer will not be found by rambling on and on about other scenarios of doubtful relevance, Takata airbags, HMI, generalities and speculations. You only need to ballpark the speed at which the dummy's head strikes the airbag to draw an inference about the outcome if it had struck the steering wheel instead. The answer is very clear from the section of video I pointed out.

The second question you had was about the possibility of a driver steering the car, assuming no airbag deployment (visibility) and no injury. Perish the thought. The total elapsed time from ditch to contact with the embankment at the end is 3 seconds, about half of which the car is fully or partially airborne. The driver would have zero chance of taking evasive action after hitting the ditch. He would still be moving violently from the landing, arms flailing helplessly or holding the steering in a useless death grip when the car hits the embankment ... and that's before we even consider reaction time.

Here's a video of the test at normal video speed, which gives a better sense of the speed and violence of the event.

https://www.youtube.com/watch?v=52bBjmqv_ws

Play it at 1/4 speed and you'll see that the vehicle plowed on one or both front wheels for more twice than it's length. You think wheel or suspension wasn't damaged by the landing so the vehicle just rolled nicely ahead? Picture of front wheel and suspension damage from the landing, which you estimate at 5-10 mph:

 

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I only did quite a bit more of that after you thought I was joking and you stated the car landing was the equivalent of a 45mph head on collision. Maybe if the car had stuck the landing and come to a complete dead stop right in that specific spot, I would easily believe that. The car is still moving quite fast after the landing.

Volvo has that embankment there to stop the car after the test because there is a road just beyond that. I do not see raised embankments in my normal driving. I do see lots of ditches, most times on the other side of the ditch is opposing traffic, a house, a parking lot, trees, etc, not an extra raised embankment made of soft dirt. Your 3 seconds is irrelevant as who knows what might really happen. Interesting though how City Safety/Forward Collision warning is ok giving a distracted driver way less then 3 seconds to react, but now in this thread, 3 seconds isn't enough.

If you watch the side view video of an iihs front impact crash, the airbags are going off before the dummies even have a chance to move forward. In your above video, you can clearly see the dummy moving forward then back at takeoff and then at landing, 0.34, moving forward again and then the airbag goes off after a delay and you see the driver snapped back by it. This is the most common way to get seriously hurt by an airbag, being both closer to it when it goes off and having it snap you back. This really seems like a lower threshold accident, one that allowed more fwd movement in the dummies but didn't trigger the airbags right away. Was it just a hair above the threshold, way above, who knows.

There have been IIHS frontal crash tests where the bags went off late, after the dummy had moved fwd some distance and the IIHS gave a lower score. Manufacturers responded and 'fixed' their timing. There's this "in-between" gray area of lower impact accidents that do cause and allow forward movement before bags maybe go off and the above scenario appears to look like that.

I don't have the answers for these scenarios. Maybe this gray area involves "luck" in that maybe it did or didn't go off. We are just going to have to agree to disagree. You've made up your mind. I haven't made up my mind either way.
 

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.... you stated the car landing was the equivalent of a 45mph head on collision. ...
No, I didn't. Here's what I actually said, quoting in full:

Calhon said:
Patty, the test is conducted at 50 mph. After going completely airborne, the car hits the ground head-first at a speed of maybe 45 mph. If the airbag didn't deploy, the driver's head would hit the steering wheel with sufficient force to cause major injuries and he would be in no position to control the car. In my opinion, the driver would be merely along for the ride once the car hit the ditch.
Head-first simply means the car landed front-first as opposed to, say, rear-first.

As for the rest, you're just evading the central issue, which is speed at which the dummy's head would have hit the steering wheel had the airbag not deployed. So let's just call it a day.
 

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No, I didn't. Here's what I actually said, quoting in full:
So car hits a slight dip in the road doing 70 on the interstate, gets .01" of air and lands like you say "head first doing 70", should the air bag still go off?

Your reply seemed to want to imply a way worse impact because immediately after that you state "major injuries" which we simply have no way of knowing.

As for the rest, you're just evading the central issue, which is speed at which the dummy's head would have hit the steering wheel had the airbag not deployed. So let's just call it a day.
I'm not avoiding it, I've been questioning what the speed and injuries would have been.

You are avoiding the issue of what potential injuries can occur from the airbag deployments themselves.
 

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I have heard of airbags killing children, and possibly small women. But it seems to be very rare.

Incidentally, speaking of children, only the two front seats in the XC90 have the collapsible bases.
 

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No question airbags can hurt you.

If they deploy in an accident they certainly do more good than harm, though.

But a random deployment would cause injury. There's a lot of force in an airbag. It's not like a big puffy cloud.
 
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