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Rationalizing a decision to skydive

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Board the plane and just soak it all in. Before you reach the jumping altitude (between 9,500 feet and 17,500 feet) the instructor will clip your harness onto theirs. At this point you are literally joined at the hip.

Steps (from http://www.wikihow.com/Skydive-for-the-First-Time):
1. Go to the United States Parachute Association’s website to locate the nearest affiliated dropzone.
2. Call the drop zone and ask about their hours and schedule a skydive.
3. Get all of your questions answered before you pay for the jump. Don’t be afraid to ask whatever is on your mind because they’ve probably already heard your question before from someone else.
4. Choose the method of your first jump.
The vast majority of people choose to make a tandem jump. This involves jumping out of the plane while attached via a harness to an instructor who wears a parachute big enough for both of you. It requires very little training and you can just “sit back and enjoy the ride” while the instructor handles all the technical parts of the skydive.
Another type of jump called an AFF (Accelerated Free Fall) Level One jump is offered at most drop zones. The training for this skydive involves a ground school course taking approximately 5-6 hours followed by a jump with your own parachute. On this type of jump, you will have two experienced instructors holding onto you during your exit from the plane and subsequent freefall in order to assist you with proper body positioning as well as initiating the canopy opening. You will also have the assistance of an instructor on the ground who is in communication with you via radio to assist with your landing pattern and proper “flaring” for landing.
One additional option you may encounter is a “static line” jump. This jump includes the same training as an AFF Level 1 jump however upon exiting the plane, your parachute is automatically deployed by a “line” attached to the aircraft. Static line jumps have generally decreased in popularity in recent years, and most first-timers end up making either a tandem or AFF Level 1 jump.
5. On the day of the jump, dress for the weather on the ground and wear sneakers. Bring an extra layer if you want but part of the fun is feeling the rush of air and although it is colder at altitude, you probably won’t notice the difference because of all the adrenaline.
6. Arrive before your appointment time but be prepared to wait for instructors to become available, the weather to break, etc. Even though you’ll only be freefalling for a minute, plan on being there for the entire day just in case.
7. Pay attention. Before your jump, you will get a briefing and meet your instructor; this will help you enjoy your skydive much more. They will fit you into a harness that will connect to the instructor and the parachute.
8. Board the plane and just soak it all in. Before you reach the jumping altitude (between 9,500 feet and 17,500 feet) the instructor will clip your harness onto theirs. At this point you are literally joined at the hip.
9. Exit the plane. Listen to your instructor on how they want you to do this because every plane and every instructor/student combination is different.
10. Enjoy it! Enjoy the feeling of falling at 120 miles an hour and feeling free as a bird. The sensation is like no other, it feels like you are floating but the rush of air tells you that you are falling
11. Enjoy the view. Once the instructor deploys the parachute you have a 360 degree view of the beautiful earth from about 5,000 feet. Your instructor may loosen your harness at this point for your comfort. Don’t worry, they won’t drop you!
12. Land safely. Once again, listen to your instructor on how to land. Sometimes you’ll stand up for the landing, other times you’ll slide in softly. It depends on a lot of factors.
13. Brag. You just did something that most people don’t have the courage to do. Enjoy the accomplishment.
14. Get certified. If you enjoyed your first skydive and want to do it again, talk to the instructors and the people at the drop zone about how to get certified. It takes a lot of time, money, and effort but you’ll find that skydivers are among the happiest people on the face of the earth.

From: http://www.howstuffworks.com/skydiving.htm
Have you ever wondered how skydiving works?
What kind of equipment do skydivers use?
How safe is skydiving as a sport?
How do you become a skydiver and how much does it cost?

A Typical Skydiver Jump
There are thousands of experienced skydivers in the United States who have hundreds or thousands of jumps under their belts. They typically own their own parachutes, pack their own parachutes and skydive every weekend. A typical jump for this kind of enthusiast goes something like this:
•The skydiver packs his or her parachute and checks it.
•The skydiver turns on and checks the AAD (automatic activation device).
•The skydiver puts on his/her jumpsuit and parachute. Typically, another jumper will check the straps and the rig to make sure everything looks OK.
•The skydiver gets on the plane. Depending on the size of the plane, there might be up to 20 jumpers sharing a ride.
•The plane flies to the jump altitude. A typical altitude might be around 13,000 feet (4,000 meters), which gives the jumper about 60 seconds of free fall — the term used in skydiving to describe the moment the jumper exits the plane. It is possible to go as high as 16,000 feet (4,900 meters) without supplemental oxygen, giving the jumper up to 75 seconds of free fall.
•When the plane is lined up properly over the jump site, the skydivers jump out of the plane.
•At about 2,500 feet (760 meters), the skydiver throws out a pilot chute, and it deploys the parachute. In the case of tandem skydiving, a drogue chute is used to regulate the fall rate.
•The skydiver steers the parachute to line up for the landing, and lands.

Skydiving Equipment
A parachute rig used by any sport skydiver today has six basic parts:
•There is the parachute itself, also known as the main canopy.
•There is the pilot chute — a small (12 to 18-inch / 30 to 45-centimeter diameter) parachute that the skydiver uses to pull out and open the main canopy. The skydiver throws out the pilot. It catches the wind and pulls on a 7 to 10-foot (2 to 3-meter) long piece of nylon webbing (known as the bridle). The bridle pulls the main canopy out of the container so that it can inflate.
•There is a second parachute, known as the reserve, that is available in case the main canopy fails for some reason. The main canopy might not come out of its container, it might not inflate properly, it might get tangled in its lines, and so on. If it fails, the skydiver can cut it away and deploy the reserve.
•There is the container, which is a backpack that holds the main chute and the reserve chute. The container also includes thick shoulder and leg straps that keep the container firmly attached to the skydiver.
•There are the lines, which run from the parachute to the container through a pair of thick straps called the risers. Most modern parachutes have five sets of lines called the A-lines, B-lines, C-lines, D-lines and brake lines.
•There is the AAD, also known as the automatic activation device. If something goes wrong — for example, the skydiver passes out or gets distracted — the AAD will automatically release the reserve parachute at about 750 feet (230 meters).
Just about everyone today uses ram-air canopies. This type of parachute is square or rectangular and is made completely out of lightweight nylon. There is a top and bottom sheet of nylon, and then a set of fabric ribs between them. The ribs divide the parachute into a set of individual cells. Air enters, or rams, into the front of the canopy to inflate the cells and give the parachute an airfoil shape. This shape makes the parachute act like a wing. Instead of coming straight down like you would with a round parachute, you actually glide in with a ram-air chute.
You also have a lot of control with a ram-air chute. You have two sets of lines connecting to the rear edge of the parachute on the left and right sides. You control these lines with two handles called toggles. When you pull on the left toggle, you lower the back part of the left side of the wing. This causes the left side of the parachute to slow down, so you turn to the left. You can turn to the right in the same way. If you pull both the left and right toggles together, it slows the whole wing down and acts like a brake. This allows you to flare to a stop during landing. This level of control makes extremely precise landings possible.

Packing a Parachute
A parachute is like a little nylon machine with all of the parts designed for light weight, durability and as few problems as possible during deployment. Considering the speed at which a skydiver is typically free falling — about 120 mph (193 kph) — and the lack of options if something goes wrong, a parachute rig needs to be incredibly reliable.

There’s a lot of popular interest in the fine art of parachute packing. It has all the elements of great drama — a person is folding a piece of fabric and stuffing it into a very small bag, and there’s another person whose life literally depends on that fabric unfolding properly. When a parachute deploys, it needs to:
•Unfold reliably, so the entire parachute inflates correctly
•Unfold consistently, so the skydiver knows what to expect when the parachute opens
•Unfold without twisting, so the skydiver is facing the right direction after deployment
•Unfold without tangling the lines
•Unfold at the right pace – If it unfolds too quickly, it can hurt the skydiver and/or damage the equipment.
The best way for a skydiver to make sure that all of this happens is to pack the parachute carefully and follow the manufacturer’s folding instructions. Most experienced skydivers do their own packing, and it takes 10 to 15 minutes to do the job.

One of the things that makes modern parachute packing so interesting is the use of zero-porosity fabric. Zero-porosity means that the fabric has a coating so that air cannot move through it. Zero-P gives the canopy better performance, but it also means that it can be very hard to get all the air out of the parachute during folding.

PARACHUTE DEPLOYMENT SEQUENCE
Here’s what happens when a parachute deploys normally:
•The skydiver uses the pilot chute to start the deployment sequence. The drogue normally rides in a little pouch attached to the bottom of the container (BOC). To deploy, the skydiver pulls the drogue out of the pouch and lets go of it.
•The bridle continues to pull out of the container.
•One end of the bridle connects to the pilot chute. The bridle’s other end connects to a bag called the deployment bag, or D-bag. When you pack the parachute, you stuff it into the D-bag, and then load the D-bag into the container. The bridle pulls the D-bag out of the container.
•All of the parachute’s lines have been stowed in a zig-zag pattern by looping them underneath rubber bands attached to the D-bag. As the pilot chute and bridle continue to pull on the D-bag, all of the lines unfold and stretch out.
•As the lines completely unfold and start to pull with the tension from the pilot chute, they pull the risers out of the container. The risers are heavy nylon straps that connect the lines to the container. (The risers also contain a release mechanism for the main canopy’s lines in case you need to cut the main canopy away.)
•The tension on the lines also pulls the parachute itself out of the deployment bag.
•The wind inflates the cells of the canopy. What you do not want, however, is for the canopy to open instantaneously. If it opens instantaneously, you go from 120 mph to 10 mph too quickly. This hurts and can also damage equipment — it can snap lines or rip the canopy. Therefore, all ram-air canopies have a piece of nylon called a slider that holds the lines together and slides down the lines as the parachute opens. This slows down the opening and keeps the lines from tangling as the parachute inflates.
Once the parachute is out and open, the skydiver looks up to make sure everything is OK. Then the skydiver can grab the two toggles and start steering the parachute toward the landing site.

RESERVE DEPLOYMENT
Let’s say you try to deploy your main canopy and something goes wrong. For example:

•The main canopy never comes out of the deployment bag.
•The main canopy does not inflate.
•The main canopy gets tangled in the lines.
•Some of the lines break, or the canopy rips during opening.
•Part of the main canopy inflates while another part does not.
In all of these cases, you have a canopy that you cannot use to land safely. You need to cut away the main canopy and deploy the reserve.

All modern rigs have a mechanism called a three-ring release that connects the main canopy to the container.
To cut away the main, you reach down and pull the release handle attached to one of your shoulder straps. This handle releases the lines on both risers simultaneously. You are now in free fall again. Then, one of two things happens:

•On some rigs, there is a cord called the reserve static line that automatically pulls out the reserve when you cut away the main.
•On other rigs, you pull a second handle to deploy the reserve manually.
In either case, you are praying that the reserve deploys cleanly and you have a good canopy when you get done. Most experienced skydivers pack their own parachutes, but it is common for the reserve chute to be packed by a certified rigger. Every few months, the reserve is unpacked and repacked to keep it from getting stiff.

AAD: AUTOMATIC ACTIVATION DEVICE
There’s not a lot of room for error in skydiving. Let’s say that one of the following three things happens during a skydive:

1.You lose consciousness as you are exiting the plane or falling.
2.You lose track of your altitude because you get distracted.
3.Something completely unexpected happens — maybe an airplane or a second skydiver flies too close to you and either damages your equipment or makes you unstable.
In any of these situations, you may be unable to deploy your parachute yourself, and you need some help. An AAD (automatic activation device) is a small computer that constantly monitors the altitude and activates the reserve chute for you.

One of the best-known AADs is the CYPRES AAD. CYPRES is short for “Cybernetic Parachute Release System.” According to the manufacturer, there are more than 65,000 CYPRES units in the field.

The CYPRES unit has four parts:
•A small display that lets your turn it on and monitor its activity
•The computer itself
•The battery
•The cutter, which actually deploys the reserve chute
The cutter is fascinating. It is essentially a bullet, and the computer sends it a signal when it is time to deploy the reserve chute. The cutter fires. The tip of the cutter is wedge-shaped, like a knife, and it cuts a piece of cord called the closing loop. The closing pin for the reserve chute hooks through the closing loop to hold the reserve chute in the container. Cutting the closing loop is the surest way possible to deploy the reserve.

The computer has the non-trivial job of deciding when it is time to deploy the reserve. The basic goal is to always deploy the reserve chute if the skydiver is in free fall and makes it down to 750 feet (230 meters) in altitude. However, this is not as easy as it sounds. Here are some of the situations that the computer has to handle to avoid erroneous deployments:

•Normal flying under a successfully deployed main cute
•Quick, unexpected pressure changes caused by rolling over (front to back) or flying around other skydivers in free fall
•Return to the ground in the airplane (rather than jumping)
•Significant pressure changes caused by the weather (e.g., a low-pressure system moving into the area)
Only if the skydiver is in free fall at 750 feet will the CYPRES unit cut the reserve loop.

The skydiver turns on the CYPRES on the ground. The CYPRES computer takes a measurement of air pressure on the ground and uses this to determine the skydiver’s altitude throughout the day. Whenever the skydiver is on the ground, the unit recalibrates every 30 seconds to handle weather-based changes in atmospheric pressure.

A typical tandem jump looks a lot like a normal jump. Here are the big differences:
•An experienced skydiver can simply leap from the plane. In a tandem jump, the student and the tandem instructor are strapped together, so there is a little more maneuvering to get ready for the jump.
•Just after jumping out, the instructor throws out a large (approx. 4-foot/1.2-m diameter) drogue chute, and this drogue is out during the entire free fall. Without this drogue, the combined weight of the instructor and student would cause the pair to fall at 180 to 200 mph (290 to 320 kph) — much faster than the normal 120 mph. The drogue slows the pair down to the normal falling speed.

Skydiving Costs
One of the most popular skydiving techniques in use today is called Accelerated Free Fall (AFF). In the United States, the student might go through the following steps to become a licensed skydiver:

•The student probably starts with one tandem jump in order to get a little experience jumping out of the plane and working in free fall. This jump typically costs between $150 and $200.
•The student then takes ground school to prepare for the first AFF jump, and then makes the first jump. In the first several AFF jumps, the student leaves the airplane with two instructors and they all fall together, with the instructors holding on to the student. The cost for ground school plus the first jump with two instructors is typically $300 or so.
•The student then makes two to three more jumps with two instructors, at a rate of around $180 to $200 per jump.
•The student then makes four to five more jumps with just one instructor, at a cost of about $150 for each jump.
•The student is then cleared to jump solo with minimal supervision. The student must complete 20 jumps, pass a test and meet other criteria to get an A License from the United States Parachuting Association.
Once you have your A license, you are generally free to jump at most drop zones, and you pay $15 to $25 per jump.

HOW DANGEROUS IS SKYDIVING?
Each year, about 30 people die in parachuting accidents in the United States, or roughly one person per 100,000 jumps.
If you make one jump in a year, your chance of dying is 1 in 100,000.
If you drive 10,000 miles per year, your chance of dying in a car wreck in any given year is something like 1 in 6,000. In other words, we accept a higher level of risk by getting into our cars every day than people do by occasionally skydiving. You would have to jump 17 times per year for your risk of dying in a skydiving accident to equal your risk of dying in a car accident if you drive 10,000 miles per year.

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Written by blueroselady

June 8, 2010 at 11:33 am

Posted in sports

Tagged with ,

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