How Do Parachutes Work?

The parachute creates a drag that slows down someone or something from falling down. Drag is the push on something from the air or water. As air is much thinner than water it doesn’t have as much drag. The larger is the surface area, the more is the drag.

The parachute is very light in weight and has a very big surface area. It catches lots of air in it as it falls down thereby creating so much of drag.

It works on the concept of ‘Whatever is thrown up always falls down’. Law of gravity states the force that comes from the center of the earth attracts everything to the earth. In fact, this is the very reason why we are able to walk on the earth. Parachute is one of those objects that follow this law of gravity. These were initially designed with an intention to save people in emergency situations when they needed to exit off a plane that is not functioning properly.

Parachutes have the air resistance, which prevents people from falling down. The fall of an object depends upon the weight it bears. The lighter it is, the quicker it reaches the ground. The air carries the atoms and molecules that these objects push their way through in order to get to their destination. The rocks, being relatively heavier than the other objects, can push the air molecules out of their way. But objects as light as feathers find it difficult to pass their way through these air molecules.

Parachutes were very amusing when you’re a kid. They are common science projects at school. They are fairly easy to make and require only inexpensive materials. However in the real world, using a parachute while free falling has serious implications. If the parachute does not deploy at the right moment, the person can fall to their death.

Fortunately they have gone through developments and trials throughout the decades for safer landings. Understanding the principle behind a parachute is easy but understanding how parachutes work is essential. By knowing the correct sequence of deployment you’ll know that you will be able to make it to the ground in one piece.

Parachutes are packed by the owners themselves or parachute riggers. They must be packed properly so that they will deploy correctly. It would take a lot of effort to pack a parachute. Modern designs have zero porosity which means the air can’t pass through the fabric, making harder to fold.

A reserve is also packed along with the main parachute in case something goes wrong. The reserve is also packed by rigger. Is taken out and repacked again every couple of months so that it won’t get stiff.

Deployment sequence

In a normal situation the deployment sequence has steps. To start the sequence the skydiver pulls out the drogue chute. It’s inside a little pouch placed at the bottom of the container or knapsack. When the drogue inflates it pulls the bridle.

The bridle is a nylon webbing which is ten to twenty feet long. This in turn pulls the closing pin. The pin holds the canopy. When the pin is pulled it gives out a small pop.

The other end of the bridle is connected to the deployment bag. The deployment bag contains the lines placed in a zig zag pattern underneath and the parachute. As the drogue and the bridle continue to pull upward, all the lines will be unfolded and stretch out. The line in turn, pulls out the risers as it continues to unfold. The risers have nylon straps that connect the lines and the parachute to the container which is carried by the skydiver.

The parachute is pulled out of the deployment bag by the tension in the lines. The wind then inflates the canopy. Modern designs called Ram-air parachutes have sliders. They hold the lines together and prevent the canopy from opening to quickly. If that opens it can cause a tear in the canopy and/or hurt the skydiver.

When the parachute is completely out and opened the skydiver can grab the toggles to be able to steer the parachute towards the landing site.

Unfortunately there is still the possibility of something going wrong. A part of the main canopy may not inflate or entirely at all, it may get tangled in the lines, rips or never comes out of the deployment bag. If any of this happens the skydiver can deploy the reserve.

You have to cut away the main canopy first to be able to do this. A release handle can be pulled out of your shoulder straps to cut away the main canopy.

After that, either the reserve deploys automatically due to the reserve static line. On other designs the skydiver has to pull out a second handle to release the reserve. Let’s just hope in both of these cases he reserve deploys correctly.