Air bags also have insecure side. It has been calculated that if cars traveling at a speed of 60km, suddenly hit the stopped vehicles will be within 0.2 seconds, and the balloon will pop up at about 300km/h, and the resulting impact force of about 180 kg, which is more vulnerable parts of the body such as the head, neck, it's hard to. Therefore, if the air bags pop angle, slight mistake, it is possible to make a "tragedy".
1. the air bag may be at a very low speed when turned on. Cars traveling at low speed when the collision occurred, crew and driver's seat belt, and did not require air bags for protection. If the balloon will cause unnecessary waste, and even may increase airbag collision damage.
2. balloon launch would harm the crew. Airbag system starts to burst the balloon cover and inflate in an instant, is likely to impact on the crew; also burns hot gases generated by the crew and pilots.
3. when passengers off their seats or seat when no one or children travelling on airbag system start up not only not given due protection, may also cause some injury to crew.