If you are like me and are always wondering "what would I do if...."
this is one answer that should ease your mind...
How to Get out of a Car That's Hanging over a Cliff
In almost all serious auto accidents, your best chance of survival is if you manage to stay inside the protective cage of the car. But if your car goes over a cliff, you don't want to be in it. If you're "lucky" enough to have your vehicle stop at (rather than hurtle over) the edge of the cliff, with one set of tires dangling precariously over nothing but thin air, will you know how to escape before the car plummets to the bottom?
Stay calm. It's quite a shock to find yourself teetering on the edge of a cliff, but the more calm and methodical you are, the better your chance of escape. Unless the car is rolling or shifting--in which case you just need to get out as quickly as possible--take a moment to determine your best route of escape.
Keep your foot on the brake. If you came to a rest with your foot on the brake pedal, leave it there until you can set the parking brake. It may be the only thing that's preventing you from rolling off the cliff.
Set the parking brake. Pull the brake handle very slowly and smoothly, and stop if you detect any movement. If your foot is on the brake pedal, slowly remove it.
Open the windows. If you have to move within the car to get to a safe exit door, prepare for the possibility that you may need to exit through the window. If you have electric windows, roll the window of the target door down before you leave the drivers seat (only do this if you can do so without starting the vehicle). If you won't be able to roll the window down, pick up a small tool that you can use to smash it, such as a wrench or screwdriver, and bring it with you when you move to the door. You only want to try a window if the door won't open or if opening the door will cause the vehicle to shift.
Turn off the vehicle. If your car is still running, turn it off.
Take off your seat belt. When you unbuckle it, make sure that it's positioned so that you won't get tangled up in it when you try to move. Instruct your passengers to do the same.
Unlock the doors In the confusion of the situation, it's easy to forget that the doors are locked. If this happens, you or your passengers may panic when you try to open the door and it doesn't open. A person who panics may try to force the door open, and their movements may cause the vehicle to shift. It's especially important to remember to unlock the doors if you have passengers in the back seat, such as small children, who may not be able to unlock their doors.
Move in planned unison. If there are multiple people in the car, make a plan before anybody moves. Typically, those who are seated closest to the cliff's edge should get out first if possible. This will maintain a favorable balance of weight in the vehicle. They should climb over the other passenger(s) if necessary, but this should be done as smoothly as possible. If people can get out simultaneously--if the only occupants are in the front of the vehicle, for example, and they can both exit the doors nearest them--they should exit at the same time.
Watch, listen, and feel for movement. If you feel, hear, or see a slight movement, immediately stop what you're doing. Your instinct will probably be to push off from the car and leap out as quickly as possible, but this is not wise if there are other passengers who have not yet exited the vehicle. Instead, stop for a moment to see if the movement stops. If you detect a more pronounced movement or movement that doesn't immediately stop, it's time to scramble out as quickly as possible and hope for the best.
Leave everything behind. It should be obvious, but don't try to take anything with you (except, perhaps, your cell phone if it's in reach). Trying to carry things out of the car will make it more difficult for you to exit, and even picking things up or rearranging them may cause the vehicle to become suddenly and fatally unstable.
Infants and small children should be passed through the window or door from a person inside the vehicle to one outside. If no one is outside yet, and you cannot safely carry an infant with you out of the vehicle, reach out the door to put the child on the ground or, if you cannot open the door, toss the child out of the window, aiming for a good landing space such as a bush or patch of grass.
If the rear of the vehicle is on the safest ground it might be worth opening the boot/trunk (there is often a control at the driver's seat) and everybody moving back until they are seated on the back of the car with legs hanging outside before everybody steps off together. Depending on the car's design, you might need to fold down rear seats to do this.
Unless you are someplace really isolated, consider just staying put and waiting for rescuers! Any movement, no matter how careful, can disturb the vehicle's delicate balance... and if you are the driver, you are probably sitting on or forward of the balance point, making even the slightest movement VERY dangerous. If you are safe for the time being, don't put yourself or others at risk by trying to get out. Trained rescuers will have equipment, numbers, and experience which could prove vital in saving you and maybe even your car.
Do not attempt to start the car when you are balanced on the edge of a cliff. A lot of movement occurs when a car starts or while the motor is running. Unless you're absolutely sure you can move the vehicle out of danger, don't risk it.
Once outside, keep your distance from the car, and do not try to reenter it. If you're lucky enough to get out of the car, don't risk going back in to get something. Don't even lean in. Just stay away.