Can You Open a Car Door Underwater?

Contrary to what many believe, car drownings are rare. It’s just that they happen so often in action films that we assume that people often drown in vehicles. Nevertheless, it doesn’t hurt to know what to do if you find yourself submerging underwater in a car.

You can open a car door underwater. However, to successfully open a car door underwater, you have to wait until the pressure inside the car matches the pressure outside. The outside and inside pressures match when the entire vehicle fills with water.

This piece will explain in careful detail how to open a car door underwater. It will also divulge why it is safer for you to escape a drowning car through the window rather than the door.

Opening car door underwater.

How to Open a Car Door Underwater

As stated above, it’s improbable but not impossible to find yourself drowning in your car. Drowning in a rapidly sinking mental enclosure seems daunting.

You can open a car door underwater by following these steps:

  1. Don’t panic.
  2. Wait for the water to fill to your chin.
  3. Open the door after the cabin fills with water.

Read on to find out how adhering to the above steps will help you open your car door.

1. Don’t Panic

It might seem improbable, but you might find yourself hurtling towards a waterbody in your car. Thinking of it is daunting enough, let alone being in the driver’s seat.

Nevertheless, try as much as possible not to panic. You have two minutes to get out of the vehicle; therefore, it is paramount that you keep a cool head.

If you are driving, keep your hands on the steering wheel, keep your safety belt buckled, and brace for impact. The car’s impact on the water can equal a similar impact on a wall.

If the crash renders you unconscious, the chances of escape drop to zero. However, people rarely get injured when cars crash into water bodies.

You can try rolling the windows down before you hit the water, especially if you are on the passenger’s side.

Once you hit the water, attempt to open the door immediately. Experts state that opening the door is near impossible, but experiments suggest that you can open the door if the water body is relatively small.

If you encounter any resistance, stop trying to open the door. The door doesn’t open immediately because the weight of the surrounding water presses against the door.

2. Wait for the Water to Fill to Your Chin

It won’t take long for water to start filling the cabin. You need to be ready when you open the door to escape.

If you’d managed to open a window, the car will fill up much faster. Modern vehicles come with insulated electrics that will work for several seconds even after the car hits the water.

Try opening the windows before the water reaches window level. If you wait for the water to reach the windows, the outside pressure will prevent you from rolling them down.

If the electrics fail, find something to help you break the window. A blow with an emergency hammer will create a crack, and the water pressure will reduce the window to pieces.

A removable headrest or an old spark plug in your glove compartment will do the trick. Strike the lower corner of the window with all your strength until the glass shatters.

Consider removing the front headrests if you have passengers behind. It will make it easier for the passengers at the back to access the front windows if that is the only means of escape.

Do not unbuckle your seatbelt, as it is essential for you to remain in place as the water fills.

It’s unlikely for a drowning car to sink evenly. The vehicle will sink faster on the side nearer to the engine: A front-engine car sinks hood-first, and a rear-engine car plunges boot-first.

Resist the urge to chase the last bits of air in the car. Remember that you have a limited time to get out of the vehicle.

Your only thought should be getting out of that sinking car.

As the water nears your chin, take and hold a deep breath.

3. Open the Door After the Cabin Fills With Water

Science and experts state that the car door will open once the cabin fills with water. The cabin should fill up seconds after you hold your breath.

Once the pressure inside the car matches the pressure outside, the car door should open.

If you kept calm and held your breath, you should easily float to the surface, leaving your car to continue its descent.

Take Away 

A lot about your escape from a sinking car through the door hinges on your ability to keep calm.

It allows you to assess the situation, come up with a life-saving solution. You should save yourself in 120 seconds, but it all depends on your ability to keep calm.

Science states that you should open your car door once the car’s cabin fills with water.

However, the safest way to save yourself from a drowning car doesn’t involve waiting for the car to fill with water.

It’s Safer to Escape Through the Window

You should get out of a drowning car as fast as possible. The easiest way to achieve that is by getting out through the window.

Regardless of what the science says, a car door will sometimes refuse to open even when you wait for the cabin to fill with water.

An experiment by Richard Hammond of Top Gear demonstrated that there is no guarantee that a drowning car’s door will open because the car is entirely underwater. Here’s a video of the experiment if you’d like to take a look:

Richard suggested that a car experiences uneven pressure as it sinks to the bottom. Therefore, the pressure only equalizes after the car hits the bottom of the water body.

If the waterbody is deep enough, you’ll be long gone before the car hits the bed.

Adam of MythBusters performed a similar experiment and found results similar to Top Gear’s. The pressure didn’t equalize immediately after water filled the cabin.

Richard and Adam both ran out of breath before they could open the car door. Mind you, the pair performed their experiments in swimming pools.

It would probably take a while longer for the pressure to equalize in, say, a lake.

Therefore, to increase your chances of escaping a drowning car, endeavor to exit immediately.

Before and shortly after you hit the surface of the vehicle, try opening the window. If there is a wide enough gap, escape the wreckage of your car.

If the water fries your electrics before you get the window open, search for something to break the car window with. The car headrest will work just fine.

Focus your blows on the lower corner of the window. It will shatter the window, allowing you to escape.

If the water level has reached the window, brace for the flood of water that will pass through the space left by the window. Keep calm and escape.


Your car door will open underwater, but you will have to wait until the pressure outside matches the pressure inside.

Some experts suggest that equalization happens after water fills the cabin, but experiments suggest that it takes longer.

The safest way to exit a drowning car is through the window.

Open it before the electrics die, and if you miss that opportunity, break the window using anything you can get your hands on.



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