pressure on plane is a process in which conditioned air is pumped into the cabin of an aircraft or spacecraft in order to create a safe and comfortable environment for passengers and crew flying at high altitudes.
For any airplane to fly, it must be able to lift the weight of the airplane, its fuel, the passengers, and the cargo. The wings generate most of the lift to hold the plane in the air.
To generate lift, the airplane must be pushed through the air. The engines, which are usually located beneath the wings, provide the thrust to push the airplane forward through the air.
Whether you’re flying in a massive Airbus A380 or a smaller regional jet (RJ), it probably has a pressurized cabin. With the exception of certain military aircraft, all airplanes have a pressurized cabin. It’s an integral part of designing an aircraft. So, what’s the purpose of a pressurized cabin exactly?
How Cabins Are Pressurized?
Airplane cabins are pressurized by forcing air into the cabin. Just like you pressurize a car tire by flowing air into it, airplanes do the same for the cabin. Air is pumped into the cabin, and because the cabin is sealed, the pressure increases.
Normally, this pressure is created by the engines used to power the airplane. As the engines turn fuel and generate combustion, some of the air is forced into the cabin to achieve an appropriate pressure on plane.
Why Pressurized Cabins Are Necessary?
Cabins are pressurized to create a safe and comfortable environment for pilots, crew, and passengers. Most commercial airplanes fly at around 30,000 to 40,000 feet above sea level.
At high altitudes such as this, the air is thinner than it is on the ground. And being that humans have evolved on land, our lungs are designed to breathe this thin air.
If someone is forced to breathe the air at 30,000 feet, he or she may experience a medical condition known as hypoxia, which is characterized by a lack of oxygen to the brain. Pressurizing the cabin, however, creates a suitable environment with more oxygen, which is essential for our health and wellness.
The use of a pressurized cabin is essential for creating a safe environment for passengers, but it does carry the risk of a blowout. If a window breaks or an emergency door opens, everything will be sucked out as the pressure attempts to equalize.
The highly pressurized air inside the cabin will travel outside of the airplane where the pressure is much lower.
Some people assume that only the cabin of an airplane is pressurized, but this isn’t necessarily true. In many cases, the entire fuselage is pressurized, including the cargo hold. This means all checked luggage and other cargo the plane is carrying is under the same pressure on plane.
To recap, airplanes are pressurized because it protects pilot, crew, and passengers from hypoxia. Airplanes are designed to pump air into the cabin to mimic the 14.7 pounds per square (PSI) of pressure that’s found at sea level.
Aircraft Pressurization Systems
A system that ensures the comfort and safety of crew and passengers by controlling the cabin pressure and the exchange of air from the inside of the aircraft to the outside.
Airplane Travel Affects Your Body
Empties your energy tank
Air pressure is lower at higher altitudes, which means your body takes in less oxygen. Airlines “pressurize” the air in the cabin, but not to sea-level pressures, so there’s still less oxygen getting to your body when you fly, which can make you feel drained or even short of breath.
The potential dehydration factor and sitting for long periods of time don’t help. Then there’s the jet lag if you’re traveling to a different time zone.
Puts stress on your ears
As the pressure on plane changes, the air pressure inside your inner ears tries to adjust with it – this equalization is what helps you maintain your balance.
Stress is placed around the middle ear tissue and eustachian tubes when the outside pressure changes quickly during takeoff and landing, which is why your ears may adjust by popping.
Makes your belly bloated
Those same pressure changes cause the gas inside your stomach and intestines to expand, which is why you may feel bloated.
What Happens When a Plane’s Cabin Depressurizes?
If depressurization happened slowly, passengers might not notice right away. They might feel woozy and drift into unconsciousness. Anyone with asthma, a heart condition, or who is elderly would feel the effects much sooner.
When a cabin depressurizes, the percentage of oxygen in the air stays about the same, but the molecules get further and further apart.
The aircraft’s engines pressurize the cabin with outside air. Compressed air gets hotter and hotter as it runs through a series of fans and rotors. Some are diverted to de-ice the wings and the rest goes through a cooling system similar to a car radiator.
Then the air expands through an expansion turbine that cools the air in the same way you can cool air by blowing it out of puckered lips. Finally, the air goes into a mixer, or manifold, and is recirculated through the cabin with a series of fans.