Airbag Failure After Collision

You did not even say what car it was or was it so badly damaged that you would not know?

The bike might have not been hit at a trigger point and all there was, was an oversteered vehicle rolling with the damage you describe.

And then

Stuff is failing for lots of reasons.

You might never know . . . .

I agree with oversteering theory which caused much damage on the car. Ground condition says the driver oversteered the car in an attempt to save bike riders.Unfortunately, he/she could not control the car due to speed factor.I don't know the exact speed of the car at the time of accident.Who Knows the car was crusing @ 150 Km/hr under the control of less experienced teenagers.From my past experience, that car can cruise at 200Km/hr with ease on highways.Car manufacturer is GM.I am not interested to disclose the brand name.

Sad to say, but there is a thriving trade in stealing air bags. eg.

...and even worse, making/selling "look-a-likes" in/from China that have no contents.....

eg. CANNOT work.....Faking I believe its called.....airbags are a common commodity of this kind - sadly!

Air bags are not a fail operate (failop) system. Look at the automotive system diagram, this is a "single string" system. Failop requires tri-plex.

In the avionics world I come from, this is considered a non-essential system for single string (10e-3 failures per hour available). Essential requires dual channel (10e-7 fail/hr), and faliop (10e-9 f/h) requires triple redundant channels (this would include 3 airbags, as you can't trust: the explosive device, the circuits that drive them, the processor channel, sensors, or bag integrity, and power supply).

Autos are poorly maintained (compared to aircraft). How often is this system tested, inspected, overhauled. Self test is not 100% coverage of all components, e.g. the accelerometer sensor.

Auto electronics is in one of the worst environments, road salt, condensing humidity, wide temperature range, vibration. Then you have surface mount (BGA) components using non lead solders (ROHS) helping to make any assembly reliability worse.

Yet we expect this system to be flawless, and deploy with 100% perfect protection.

Thanks for the valuable points.There is a rumoUr that all of them are in very kritical condition....So, today onwards I will be more carefool about accidents.ALL automobile manufacturers are simply boast about safety features of their vehicles to cheat public.

No, manufactures do the best they can to meet safety standards set by the government that regulates them. If they fail to do that, then that is their fault.

However, protecting yourself is not the responsibility of someone else, it is your job.

All these safety features are nice, but are simply second tier safety nets and you should use your brain as your first tier defense rather than point fingers at others or expect others to catch you when you fall.

Airbags typically have sensors in the front bumper. It was likely that the mass of the bike was not enough to engage the sensors.

If the vehicle had hit front on with a car or other massive object it would have been likely another story. You need to have some significant force to activate these sensors, otherwise a simple parking incident would cause them to deploy.

I guess the roll over was from a driver induced skid and none of the airbag sensors were activated or hit, just the metalwork on the sides and top of the car.

GM air bags are prone to inaction at the least opportune times.

Airbag controller should signal airbags to open only IF sustained and over a set level deceleration is sensed. That, (providing that seat belts are used also), is the only case airbags can actually help, limiting head injury. A compact 200kg metal bullet hitting your car from any direction is a totally different thing. With enough speed, it could go right through doors (I've seen results of such a case) without sometimes even giving the car body the acceleration characteristics the controller expects. But this, sadly, is not a fault. It is almost certain that in such cases it would give absolutely NO PROTECTION to car driver or passengers. It is NOT designed to protect you from external things coming in, it mainly protects you from hitting your own car (steering wheel, windscreen, etc) due to collision forces. With no belts on it might not even do that effectively. S.M.

I am surprised no one said this before now. What is wrong with you? Just what the emergency responders needed, someone stopped on the side of the road gawking and maybe increasing the chance of a secondary accident.

For the future... please clear your vehicle from the area as soon as you are able instead of pulling over to look things over. The life you may save may be another's.

If the driver swerved to avoid the cyclist, and did not have side bags and sensors, the forward accelerometer sensors may not have been activated, as the vehicle may have been going sideways at point of rollover.. You id not mention the model and year of he car. That would help us with a clue of the year of technology...

The airbag systems in modern cars are designed to trigger on specific decceleration criteria. This is in order to give the occupants the best outcome after a crash.

For example - a car is in collision with another vehicle, careens off the road and hits a tree. The airbag trigger will probably not activate on the first collision but will as the car hits the tree. This is because the first impact, even though it may have been sufficient to cause considerable damage to the cars exterior structure, is less serious to the occupants than the full stop impact against the tree.

The exterior panels/seatbelts/headrests are designed to give the first line of defence in the event of a collision and the airbags kick in only when that collision reaches the deccelaration trigger point.

I think it is a mix of sensors, some mechanical, such as a tube with a ball or mass in it that is designed to dislodge and slam into a mechanical switch, and some electronic like an accelerometer.

My guess is that manufactures probably each have their own set of preferred solutions.