its not the speed its ho hard you hit/get hit...ie if your sitting at eh lights and somone hits the back of you they wont go off but if your pushed into somone hard enough they will go off, the sensor is a little metal ball baring that sits in a spring and when that makes contact wit the sensor it will go off.
From Memory! From memory, I seem to remember a speed of about 30 KPH back when air bags were introduced. In the US where seat belt wearing is less prevalent, I think the air bags are set at 10 MHP (16 Kph) or so. And they inflate more aggressively, which has been known to kill a few children sitting in front passenger seats.
ouch. all because seatbelts are optional over there. stupid. unless they're TRYING to lower the population levels?
Yep, Yank airbags go of much harder and at a lot lower speed...quite some years ago when they were first brought out here for testing, apparently on a typical potholed outback highway at 100km/hr an American-spec airbag went off on a rough patch of corrugations.... :w00t: As a guide, go into a Jeep or Chrysler dealership and have a look at a new Jeep or other Chrysler vehicle with airbags...on the passenger side hanging from teh glovebox lid is a tag warning you not to place children in the front passenger seat or, I think, smaller-built adults. I know that in America many people die each year from airbag incidents, mostly kids and small women. Disturbingly, they warn to DEFINATELY not put one of those baby capsules in the front seat of a car with airbags, as again in the USA there have been several cases of the kid being decapitated by the airbag striking them against the edge of the capsule... :unsure: I don't like them, and if our Berlina didn't have the drivers bag, I wouldn't have ordered it as an option. The only two incidents I personally know about don't fill me with confidance. 1: my cousin was getting her husband to fit a stereo in thier VR Commodore, and as he was digging around under the dash for a power wire, he set off the airbag, which would have been a pisser except he was leaning close to the wheel at the time and ended up with a couple of beauty black eyes and a detatched retina which had to be fixed with laser treatment. 2: My nephew has pictures of a Falcon (forget the model) which was being delivered to his workplace in South Oz on a car trailer for repairs, when the driver went over a speed bump at a full seventy km/hr...he simply didn't see it as he was looking for a road sign. The drivers bag went off (Ford didn't know why, combination of the severe jolt and a possible electrical fault, which the car was coming in for) and when they inspected the inside of the car, they noticed a long cut in the hoodlining way back towards the rear window. They just put it down to an old accident, but then they found one of the "flap" bits that springs aside to let the bag out of the wheel on the rear parcel shelf! Oh, there is one more, my Boss at work drives a brand new BMW 740 sedan...mmmmmmm.... :thumbsup: . One day he turns up at work with a different black sedan, and we asked him where his car was. He got into t to drive it on the weekend, and the computer flashed a warning saying "Airbag fault, do not drive vehicle!". I am pretty sure he couldn't start it either, and BMW had to trailer it away for repairs and checks...thus explaining the loaner BMW... :bang: . He says it's a good thing it didn't happen way out back of beyond where a mechanic is likely to be challenged by anything more complicated than a red motor...
Alternate Safety Equipment Idea! A wise person once suggested that the best safety initiative would be to remove all safety fittings from around the driver, and put a 30CM sharp pointed object on the steering wheel facing the driver.
or rig the airbag trigger to set of a stick of tnt. see who wants to crash then. or to quote a documentry i saw "hydrogen cars are great, who wants to crash test em?" [this was a documentry on how eventually we will run out of oil and hydrogen cars are a nice idea but not worth it because to make the hydrogen fuel it takes a fair whack or petrolum stuff anyway.]
What sort of impact is required for the airbags to go off? My husband hit a fair sized roo a couple of weeks ago and our Commodore has driver, passenger and side airbags and none went off. Normal? I'm not sure how the airbag thing works properly - this os our first car with them fitted and we've only have it a couple of months.
I may have an idea why your airbags didn't go off when you hit the roo. To be blunt, a roo is nice and soft and squishy, and the impact may not have imparted enough kinetic energy to your car to set off the airbag...more a soft impact with gradual buildup of energy than a big solid hit all at once as if you had struck another car or a post. I don't think it's the speed that makes them go off, from what I understand about the sensor, it is the impact energy that sets them off...this leads to a situation I personally know of where a guy's car was stopped at the lights when a car cut the corner and smacked into his front right hand side. His driver bag went off and he wasn't even moving.
theres nothing soft about hitting a roo trust me........it also depends on where the roo hit your car because the sensors are only placed in certain areas on the car to avoid the airbags going off for minor incidents
Thanks guys Both your posts make sense. I'm glad that roo wasn't a big one... i was driving home last night and saw 3 on the side of the road, the biggest one was bent over eating grass and his back was higher than the guide post he was standing next to - by quite a bit. I wouldn't want to hit him! We grow 'em big round here.
The collision speed is not the primary factor in triggering the air bags but wether the air bag system senses that the impact is enough to trigger the explosives. Different manufacturers will have differing placement of sensors, differing impact levels required to activate them etc. Air bags in Australian cars are not mandatory. The Australian Design Rule that deals with frontal occupant protection requires only that manufacturers achieve given safety standards in relation to head, chest and upper leg injury. The rule does not specify the means whereby the standard is to be met. All new vehicles sold in Australia meet the standard even if air bags are not fitted. Airbags are not a soft, billowing cushion as appears to be depicted in some advertisements. To do the job it is designed for the airbag system has to sense that a crash has already commenced, which means that the front of the car is starting to crush under the impact; to determine that the impact is severe enough to trigger the operating mechanism, and to fire the explosive gas generating device that inflates the bag in time to cushion the impact of the occupant coming forward to meet the dashboard or steering wheel. This takes place within about 60 milliseconds of the impact. The bag then deflates immediately. This means that the inflating bag comes out of the steering wheel hub or dashboard at around 200km/h, and that the whole sequence takes place in less than one third of one second. In most cases the firing, inflating and deflating of the air bag will be 'lost' in the general impact and noise of the crash itself and will probably be unnoticed.
From The Australian Transport Safety Bureau How does an airbag work? An airbag system consists of the airbag module which contains an inflator, the airbag itself, and a trim cover. The proper firing of the airbag is controlled by crash sensors which supply electrical signals to a control unit which fires the inflator to inflate the airbag. The driver-side airbag module is in the hub of the steering wheel. The passenger-side airbag module (if so equipped) is in the dashboard above the glovebox. Ths is what happens when an airbag deploys in a crash: In the 15 to 20 milliseconds after impact, the crash sensors and control unit determine the severity of the collision and decide whether to deploy the airbag. At about 25 milliseconds, the airbag splits its covering pad in predetermined places and begins to inflate rapidly. At about 45 milliseconds, the bag is fully inflated while the seatbelted occupant is still moving forward. At around 60 milliseconds, the occupant contact the airbag which immediately begins to deflate via vent holes in the back. Up to 100 milliseconds, the occupant continues to sink deeply into the airbag which cushions the head and chest while it is deflating. In less than a blink of an eye, the crash has occurred, the airbag has deployed, done its job and now lies deflated in front of you. Airbags and the risk of injury to children and small adults There have been a number of media reports in recent months of crashes in the USA where unrestrained or incorrectly restrained children have been killed by airbags. A similar number of fatalitites involving small adults have also been reported. The U.S. situation Airbags are mandatory in the USA because it was the one way to ensure that occupants who do not wear seatbelts have some form of protection in crashes. The US seatbelt wearing rate is only now approaching 70%, whereas Australia has been over 95% for many years. To protect the unbelted, US airbags must fire earlier and with greater force than the systems seen in Australia. This means that small occupants and the elderly in the USA are disadvantaged and low speed crash cases are now emerging where the so called "aggressive" US airbags have caused fatal or serious injuries where these occupants have been sitting close to the airbag when it has deployed. That is why the Australian Design Rule for crash protection requires the seatbelts to be fastened, allowing the vehicle manufacturers to design their airbag systems to be a supplement to the seatbelt and therefore "softer". The Australian situation There are a number of reasons why fatalities to children and small adults should not happen in Australia. Small Adults The US airbags fire with much greater force and are designed to stay inflated longer in order to prevent the unbelted occupant from going through the windscreen. In Australia, airbags are designed as supplementary restraint systems to the lap shoulder seatbelt. As a result, the airbags fire later and inflate with less force and have larger vents which make the airbag "softer". In 1995 the Federal Office of Road Safety (FORS) commissioned a study with the Monash University Accident Research Centre (MUARC) to investigate crashes involving airbag-equipped cars. The study was aimed at not only examining the benefits of airbags but also to alert FORS of any inherent problems with airbag deployments in the real world. Currently, MUARC has investigated over one hundred cases of airbag deployment and there has not been any case of either adults or children being injured let alone killed because of the airbag deploying. Children In the 1970s, Australia led the world in child restraints by mandating their use and adopting an attachment system that incorporates an upper tether strap. Australian child restraints attach to the car via the adult belt at the bottom and to dedicated anchorage points on the vehicle by the upper tether strap. Canada followed our lead in the late 1980s. In contrast, the USA and Europe only rely on the adult belt which allows the child restraint to move around during a crash thus reducing its effectiveness. Not having an upper tether strap also allows the restraint to be used in the front passenger seat. This has recently become a concern in the USA particularly with rearward facing child restraints which are literally resting on the passenger airbag. In a crash, the US airbag inflates at over 300 km/h causing serious or fatal head injuries to the child in the restraint. The same thing happens to children who are unrestrained or incorrectly restrained in the front seat in close proximity to the airbag. These are the two scenarios currently being reported in the US by media. There have been no reports of similar problems in Australia. In Australia, the need for an upper tether strap precludes child restraints from being used in the front seat. In addition, some State laws prohibit children of certain ages from riding in the front seat. The only time children are at risk is if they are unbelted in the front seat, which is illegal. On vehicles fitted with passenger airbags, most vehicle manufacturers are voluntarily putting warning labels alerting to the dangers of having children close to the airbag in an accident. FORS has negotiated with industry to mandate the labelling requirements in the Australian Design Rules. Following representations from FORS, the latest Australian Standard for child restraints will also have labelling requirements on the child restraint itself to warn of these dangers. The US problem with airbags should not happen in Australia because: Airbags fitted to Australia cars inflate with less force than in the U S . Australian child restraints are designed for use in the rear seats . There have not been reports of similar problems in Australia. Cars and child restraints have warning labels advising of the dangers . Nevertheless, it is important to understand that the airbag is not a substitute for a seatbelt. Unrestrained children are at far greater risk of death or injury than children wearing a suitable seatbelt. Small drivers, particularly women, are advised to sit as far as is comfortable from the steering wheel. This distance should be at least 30cm (or about 1 foot). Side aribags only deploy in a side impact. Frontal airbags require enough activation of sensors consistent with sufficient speed and force throught the strike area. A roo hitting a songle point isn't enough becasue the momentum/ speed still continues. Disconnect negative battery terminal battery for 1 minute if working on electircals or worried about airbags that have'nt deployed at a prang.
Great info there mate. Many thanks. I thought that may have been the case with the roo - i mean in rural areas if a roo set off an airbag the dealers would make a mint repacking them and replacing all the bits that need it after an AB has been deployed. Thanks again.
