Showing posts with label Parachute deployment. Show all posts
Showing posts with label Parachute deployment. Show all posts

Sunday, April 8, 2012

Formation Skydiving

Formation Skydiving
Formation skydiving is the art of building formations in free-fall with multiple people gripping each others' limbs or specially built "grippers" on their jumpsuits.

Formation skydiving can be further divided into several sub-categories, so named for the number of members in a team:
  • 4-way sequential
  • 4-way vertical sequential (VRW)
  • 8-way sequential
  • 16-way sequential
  • 10-way speed
  • Large formations (Big-ways)
A competition in 4-way formation skydiving (FS-4) takes place like this:

There are two kinds of formations, called randoms and blocks. The randoms are singular formations with full separation of all grips both before and after building the formation. The blocks are double formations with a special designated movement pattern in between, called an inter. The start formation may, or may not be similar to the ending formation. The inters are differently performed. Here are some examples:

Inter 1: The grips are released between some of the flyers, so they become two pieces of two team members. they both do a 270 degree turn, and reconnect to a different formation

Inter 2: Three people stay connected, and do a 360 turn, while the last person, flies alone.

Inter 15: All grips are released and everyone does a 360 turn back to the original formation.

Blocks are designated by numbers, while randoms got letters. Blocks are worth one point for each correct formation, that makes 2 points, and randoms count as 1 point. There are 22 blocks and 16 randoms.

A competition consists of up to 10 rounds, and each round consists of 5 or 6 points, which the teams are to repeat as many times as they can within the working time of 35 seconds. The score judging are based on the videographers material.

A competition draw may look like this:

1. C-E-B-13 2. 14-20-8 3. 15-16-H 4. J-O-1-D 5. 6-18-19 6. 5-F-21 7. 10-K-G-M 8. 22-3-P 9. 12-9-4 10. 11-17-Q

The winning team will be the team that has collected most points, by completing the most correct formations within time after the final round is ended. In case of weather or technical problems, or other causes, a competition will be valid as long as all teams has completed at least one round.

The current FAI world record for largest free-fall formation is a 400-way, set on February 8, 2006 in Udon Thani, Thailand by World Team. It was held for 4.25 seconds. They used five C-130 Hercules airplanes and exited from an altitude of 25,000 feet.

A recent sub-category of formation skydiving is vertical formation skydiving (VRW). Skydivers build formations using higher-speed body positions normally associated with freeflying, such as head down and sitflying.

Source: http://en.wikipedia.org/wiki/Formation_skydiving

Variations of Skydiving

Variations of Skydiving
In addition to disciplines for which people train, purchase equipment and get coaching/lessons, the recreational skydiver finds ways to just have fun. Today, there are twelve Variations of Skydiving:

1. Hit and Rock. "Hit and Rock" is a variant of Accuracy landing devised to let people of varying skill levels compete for fun. "Hit and Rock" is originally from POPS (Parachutists Over Phorty Society). The object is to land as close as possible to the chair, remove the parachute harness, sprint to the chair, sit fully in the chair and rock back and forth at least one time. The contestant is timed from the moment that feet touch the ground until that first rock is completed. This event is considered a race.

2. Freeflying

3. Tracking. Tracking is where skydivers take a body position to achieve a high forward speed, flying their body to achieve separation from other jumpers and cover distance over the ground.

4. Formation skydiving

5. Pond swooping. "Pond swooping" is a form of competitive parachuting wherein canopy pilots attempt to touch down at a glide across a small body of water, and onto the shore. Events provide lighthearted competition, rating accuracy, speed, distance and style. Points and peer approval are reduced when a participant "chows", or fails to reach shore and sinks into the water. Some danger involved with pond swooping is when pilots "chow" they land in the water and then the parachute slowly begins to sink. Some divers get tangled in the cord and are dragged to the bottom and drown. To avoid being dragged down, some divers will cut the cord if they sense that they cannot make it across to the shore.

6. Cross-country. A cross-country jump is a skydive where the participants open their parachutes immediately after jumping, with the intention of covering as much ground under canopy as possible. Usual distance from Jump Run to the dropzone can be as much as several miles.

7. Camera flying. In "camera flying", a camera person jumps with other skydivers and films them. The camera flier often wears specialized equipment, such as a winged jumpsuit to provide a greater range of fall rates, helmet-mounted video and still cameras, mouth operated camera switches, and optical sights. Some skydivers specialize in camera flying and a few earn fees for filming students on coached jumps or tandem-jumpers, or producing professional footage and photographs for the media. There is always a demand for good camera fliers in the skydiving community, as many of the competitive skydiving disciplines are judged from a video record.

8. Night jumps. Parachuting is not always restricted to daytime hours; experienced skydivers sometimes perform night jumps. For safety reasons, this requires more equipment than a usual daytime jump and in most jurisdictions requires both an advanced skydiving license (at least a B-License in the U.S.) and a meeting with the local safety official covering who will be doing what on the load. A lighted altimeter (preferably accompanied with an audible altimeter) is a must. Skydivers performing night jumps often take flashlights up with them so that they can check their canopies have properly deployed.

Visibility to other skydivers and other aircraft is also a consideration; FAA regulations require skydivers jumping at night to be wearing a light visible for three miles (5 km) in every direction, and to turn it on once they are under canopy. A chemlight(glowstick) is a good idea on a night jump.

Night jumpers should be made aware of the Dark Zone, when landing at night. Above 100 feet jumpers flying their canopy have a good view of the landing zone normally because of reflected ambient light/moon light. Once they get close to the ground, this ambient light source is lost, because of the low angle of reflection. The lower they get, the darker the ground looks. At about 100 feet and below it may seem that they are landing in a black hole. Suddenly it becomes very dark, and the jumper hits the ground soon after. This ground rush should be explained and anticipated for the first time night jumper.

9. Stuff jumps. With the availability of a rear door aircraft and a large, unpopulated space to jump over, 'stuff' jumps become possible. In these jumps the skydivers jump out with some object. Rubber raft jumps are popular, where the jumpers sit in a rubber raft. Cars, bicycles, motorcycles, vacuum cleaners, water tanks and inflatable companions have also been thrown out the back of an aircraft. At a certain height the jumpers break off from the object and deploy their parachutes, leaving it to smash into the ground at terminal velocity.

10. Skysurfing

11. Base Jumping

12. Wingsuit flying

Source: http://en.wikipedia.org/wiki/Parachuting

Parachute deployment

Parachute deployment
At a skydiver's deployment altitude, the individual manually deploys a small pilot-chute which acts as a drogue, catching air and pulling out the main parachute or the main canopy. There are two principal systems in use : the "throw-out", where the skydiver pulls a toggle attached to the top of the pilot-chute stowed in a small pocket outside the main container : and the "pull-out", where the skydiver pulls a small pad attached to the pilot-chute which is stowed inside the container.

Throw-out pilot-chute pouches are usually positioned at the bottom of the container – the B.O.C. deployment system – but older harnesses often have leg-mounted pouches. The latter are safe for flat-flying, but often unsuitable for freestyle or head-down flying.

In a typical non-military parachute system, such as the throw-out, the pilot-chute is connected to a line known as the "bridle", which is in turn attached to a small deployment bag that contains the folded parachute, with the suspension lines stowed in rubber bands. At the bottom of the container that holds the deployment bag is a closing loop which, during packing, is fed through the grommets of the four flaps that are used to close the container. At that point, a curved pin that is attached to the bridle is inserted through the closing loop. The next step involves folding the pilot-chute and placing it in a pouch (e.g. B.O.C pouch).

Activation begins when the pilot chute is thrown out. It inflates and creates drag, pulling the pin out of the closing loop and allowing the pilot-chute to pull the deployment bag from the container. The parachute lines are pulled loose from the rubber bands and extend as the canopy starts to open. A rectangular piece of fabric called the "slider" (which separates the parachute lines into four main groups fed through grommets in the four respective corners of the slider) slows the opening of the parachute and works its way down until the canopy is fully open and the slider is just above the head of the skydiver. The slider slows and controls the deployment of the parachute. Without a slider, the parachute would inflate fast, potentially damaging the parachute fabric and/or suspension lines. During a normal deployment, a skydiver will generally experience a few seconds of intense deceleration, in the realm of 3 to 4 G, while the parachute slows the descent from 120 mph (190 km/h) to approximately 18 mph.

If a skydiver experiences a malfunction of their main parachute which they cannot correct, they pull a "cut-away" handle on the front right-hand side of their harness (on the chest) which will release the main canopy from the harness/container. Once free from the malfunctioning main canopy, the reserve canopy can be activated manually by pulling a second handle on the front left harness. Some containers are fitted with a connecting line from the main to reserve parachutes – known as a reserve static line (RSL) – which pulls opens the reserve container faster than a manual release could. Whichever method is used, a spring-loaded pilotchute then extracts the reserve parachute from the upper half of the container.

Source: http://en.wikipedia.org/wiki/Parachuting

Skydiving in Indonesia

Skydiving in Indonesia
Skydiving is an air sport is very popular because it is challenging society. Humans have long wanted to make the jump, but can not be implemented because at that time there has been no proper equipment. In 1617, Fausto Veranzio became the first man to make the jump from a tower in Venice, Italy, and landed safely use tools like a parachute. While the jump from a flying object, has been implemented for the first time in 1797, namely by Andre Jacques Garnerin in Paris, France from a hot air balloon. Leslie Irvin who was saved by a parachute in an accident in England, feels indebted to the kit. Since the events that occurred in 1919, he devoted the rest of his life to develop and refine the technology and the parachute system.

But skydiving as a sport, was introduced in Indonesia for the first time in 1962 by Mladen Milicevic (Mica), a Yugoslav, who was then conjunct in the School of the Army Command in Batujajar. Since then, skydiving evolved into a more popular sport. Society's first parachute jump was Aves. Aves was established in Bandung by the ITB students with Trisnoyuwono reporters on July 29, 1969. And since then parachuting sport continues to grow in all regions in Indonesia. On January 17, 1972, parachuting clubs are located in Indonesia there are 62 clubs, they agreed to join the parent organization of FASI.

Even this sport can not be separated from technological advances, which are able to create new devices that are increasingly sophisticated. The use of new equipment by skydiving lets athletes do new maneuvers in the air is hard to do with the old type equipment. Even using the new equipment, skydiving athletes capable of making a record, a new record in a variety of race numbers.

Skydiving hold a variety of numbers including the precision landing, air cooperation, cooperation between the canopy and free style. Other numbers are formation skydiving and skysurfing. Types of parachutes used in skydiving competitions such as the type DC-5 for the precision landing, PD-150 for cooperation in the air. Achievements at the national level has been achieved is in the class co-operation in the air as much as 23 peterjun are recorded in Bali on the sidelines of the World Parachute Championships in 1989.

Saturday, April 7, 2012

Tandem skydiving

Tandem skydiving
Tandem skydiving or tandem parachuting refers to a type of skydiving where a student skydiver is connected via a harness to a tandem instructor. The instructor guides the student through the whole jump from exit through freefall, piloting the canopy, and landing. The student needs only minimal instruction before making a tandem jump. This is one of three commonly used training methods for beginning skydivers; the others being static line and Accelerated Freefall (known as Progressive Freefall in Canada).

Tandem skydiving is a very popular training method for first time skydivers, but it is more expensive than a static line skydive. It exposes first-time jumpers to skydiving with minimal expectations from the student. The training may consist of many of the activities performed by any skydiving student, for example, how to exit the aircraft, how to do maneuvers in freefall, and how to deploy the main canopy themselves. However, the tandem master remains primarily responsible for safe and timely parachute deployment.

Although it is the exception, many have commented that during a tandem skydive they experienced nausea and the feeling of passing out, which starts after the canopy deployment (never occurs during freefall) and goes away immediately after landing. It is believed to be caused primarily by the incorrect adjustment of the tandem harness affecting blood flow (this rarely occurs with a solo harness) and is more likely if the individual is at the upper end of the weight limit.

Equipment

Tandem skydiving requires equipment with several differences from normal sport skydiving rigs. All modern tandem skydiving systems use a drogue parachute, which is deployed shortly after leaving the plane in order to decrease the skydivers' terminal velocity. This is necessary for proper parachute deployment, lengthening the duration of the skydive, and allowing the skydivers to fall at the same speed as videographers. Tandem skydiving systems also use larger main parachutes (360 square feet and larger) to support the additional weight of two passengers. The FAA requires tandem parachute rigs to be equipped with a main and reserve parachute, as well as an automatic activation device (AAD), a safety device that automatically deploys the reserve parachute if it detects that the skydivers are still at freefall speed below a certain altitude.

Instructor certification

Most countries have varying laws or regulations regarding who may skydive with a passenger or student. In the United States, the FAA requires every potential instructor to have at least 3 years of experience skydiving, 500 skydives, and a master parachute license issued by an FAA-recognized organization (for the USPA, this is equivalent to a D license). Instructors are also required to pass a certification course given by the manufacturer of the tandem parachute system to be jumped. The USPA also requires potential instructors to possess a current FAA Class III Medical Certificate, and complete a USPA Tandem Instructor Rating Course.

Source: http://en.wikipedia.org/wiki/Tandem_skydiving

Training about Skydiving

Training about Skydiving
Skydiving can be practiced without jumping. Vertical wind tunnels are used to practice for free fall ("indoor skydiving" or "bodyflight"), while virtual reality parachute simulators are used to practice parachute control.

Beginning skydivers seeking training have four following options:

1. Static line
In parachuting, a static line is a cord attached at one end to the aircraft and at the other end to the top of the pilot chute inside the jumper's backpack. The parachutist's fall from the aircraft causes the static line to become taut, then it pulls the pilot chute free of the backpack. The inflation of the small pilot chute in turn causes the main canopy to be pulled out of the backpack. The continued fall of the jumper causes the main parachute lines to extend and become taut, at which point the binding that joins the static line to the pilot chute comes apart from the shock of the jumper's weight, freeing the parachute and its passenger to continue descending freely, no longer connected to the aircraft. The main parachute then inflates, braking the fall. This static line mechanism opens the parachute automatically with no action required by the passenger.

The parachutist must adopt and maintain a suitable body position throughout deployment to minimise the chances of a parachute malfunction. This method of parachute deployment is commonly used in several ways:
  • Training student skydivers
  • Base Jumping
  • Military paratroopers jumping from very low altitudes (400+ feet or 122+ meters)
  • Soviet and successor state military standard procedure for all airborne infantry jumps, regardless of altitude
Static line jumping carries risk of injury that, according to one study, doubles when performed in combat.

For training students in civilian operations, modifications to existing static line equipment may be made to simplify operations. One such modification is to attach the deployment bag to the parachute instead of the static line, which also requires some modification to allow the static line to detach, typically a Velcro fastener. This leaves much less material "in the wind" behind the plane after the jumper has left; this isn't a problem for larger cargo aircraft used in military jumping, but presents a major issue for smaller aircraft used in civilian operations. This modification also results in a somewhat slower opening, which softens the opening shock at the cost of altitude, a minor concern for jumpers exiting at 2,800 ft (850 m).

2. Instructor-assisted deployment
Instructor-assisted deployment (IAD) is a parachute deployment method most similar to static line. The main difference is that instead of being deployed by a static line, the student's jumpmaster (who is in the plane with them) deploys the student's parachute by throwing the pilot chute downward and clear of the door as the student exits.

Among the benefits to IAD is the ability to use the same parachute equipment as the students will use when they progress to deploying their parachutes on their own, and the decreased chance of an inconvenience called "line twists".

3. Accelerated freefall
4. Tandem skydiving

safety in parachuting

safety in parachuting
Despite the perception of danger, fatalities are rare. However, each year a number of people are hurt or killed parachuting worldwide. About 30 skydivers are killed each year in the US, roughly one death for every 100,000 jumps (about 0.001%).

In the US and in most of the western world skydivers are required to carry two parachutes. The reserve parachute must be periodically inspected and re-packed (whether used or not) by a certificated parachute rigger (in the US, an FAA certificated parachute rigger). Many skydivers use an automatic activation device (AAD) that opens the reserve parachute at a safe altitude in the event of failing to activate the main canopy themselves. Most skydivers wear a visual altimeter, and an increasing number also use audible altimeters fitted to their helmet.

Injuries and fatalities occurring under a fully functional parachute usually happen because the skydiver performed unsafe maneuvers or made an error in judgment while flying their canopy, typically resulting in a high speed impact with the ground or other hazards on the ground. One of the most common sources of injury is a low turn under a high-performance canopy and while swooping. Swooping is the advanced discipline of gliding parallel to the ground during landing.

Changing wind conditions are another risk factor. In conditions of strong winds, and turbulence during hot days the parachutist can be caught in downdrafts close to the ground. Shifting winds can cause a crosswind or downwind landing which have a higher high potential for injury due to the wind speed adding to the landing speed.

Another risk factor is that of "canopy collisions", or collisions between two or more skydivers under fully inflated parachutes. Canopy collisions can cause the jumpers' inflated parachutes to entangle with each other, often resulting in a sudden collapse (deflation) of one or more of the involved parachutes. When this occurs, the jumpers often must quickly perform emergency procedures (if there is sufficient altitude to do so) to "cut-away" (jettison) from their main canopies and deploy their reserve canopies. Canopy collisions are particularly dangerous when occurring at altitudes too low to allow the jumpers adequate time to safely jettison their main parachutes and fully deploy their reserve parachutes.

Equipment failure rarely causes fatalities and injuries. Approximately one in 750 deployments of a main parachute results in a malfunction. Ram-air parachutes typically spin uncontrollably when malfunctioned, and must be jettisoned before deploying the reserve parachute. Reserve parachutes are packed and deployed differently; they are also designed more conservatively and built and tested to more exacting standards so they are more reliable than main parachutes, but the real safety advantage comes from the probability of an unlikely main malfunction multiplied by the even less likely probability of a reserve malfunction. This yields an even smaller probability of a double malfunction although the possibility of a main malfunction that cannot be cutaway causing a reserve malfunction is a very real risk.

Parachuting disciplines such as BASE jumping or those that involve equipment such as wing suit flying and sky surfing have a higher risk factor due to the lower mobility of the jumper and the greater risk of entanglement. For this reason these disciplines are generally practiced by experienced jumpers.

Depictions in commercial films — notably Hollywood action movies — usually overstate the dangers of the sport. Often, the characters in such films are shown performing feats that are physically impossible without special effects assistance. In other cases, their practices would cause them to be grounded or shunned at any safety-conscious drop zone or club. USPA member drop zones in the US and Canada are required to have an experienced jumper act as a "safety officer" (in Canada DSO – Drop Zone Safety Officer; in the U.S. S&TA – Safety and Training Advisor) who is responsible for dealing with the jumpers who violate rules, regulations, or otherwise act in a fashion deemed unsafe by the appointed individual.

In many countries, either the local regulations or the liability-conscious prudence of the dropzone owners require that parachutists must have attained the age of majority before engaging in the sport.

Parachuting and weather

Parachuting in poor weather, especially with thunderstorms, high winds, and dust devils can be a dangerous activity. Reputable drop zones will suspend normal operations during inclement weather.

Canopy Collisions

A collision with another canopy is a statistical hazard, and may be avoided by observing simple principles.


Source: http://en.wikipedia.org/wiki/Parachuting

What is Parachuting

What is Parachuting
Parachuting, also known as skydiving, is the action of exiting an aircraft and returning to earth with the aid of a parachute. It may or may not involve a certain amount of free-fall, a time during which the parachute has not been deployed and the body gradually accelerates to terminal velocity.

The history of skydiving starts with Andre-Jacques Garnerin who made successful parachute jumps from a hot-air balloon in 1797. The military developed parachuting technology as a way to save aircrews from emergencies aboard balloons and aircraft in flight, later as a way of delivering soldiers to the battlefield. Early competitions date back to the 1930s, and it became an international sport in 1952.

Parachuting is performed as a recreational activity and a competitive sport, as well as for the deployment of military personnel Airborne forces and occasionally forest firefighters.

A skydiving center can be a commercial operation or a club, usually operates at an airport, and provides one or more aircraft that takes groups of skydivers up for a fee. An individual jumper can go up in a light aircraft such as a Cessna C-172 or C-182. In busier drop zones (DZ) larger aircraft may be used such as the Cessna Caravan C208, De Havilland Twin Otter DHC6 or Short Skyvan.

A typical jump involves individuals exiting an aircraft (usually an airplane, but sometimes a helicopter or even the gondola of a balloon), at anywhere from 1,000 to 4,000 meters (3,000 to 13,000 feet) altitude. If jumping from a low altitude, the parachute is deployed immediately; however, at higher altitudes, the skydiver may free-fall for a short period of time (about a minute) before activating a parachute to slow the landing down to safe speeds (about 5 to 7 minutes).

When the parachute opens (usually the parachute will be fully inflated by 800 meters or 2,600 feet) the jumper can control the direction and speed with toggles on the end of steering lines attached to the trailing edge of the parachute, and can aim for the landing site and come to a relatively gentle stop. All modern sport parachutes are self-inflating "ram-air" wings that provide control of speed and direction similar to the related paragliders. Purists in either sport would note that paragliders have much greater lift and range, but that parachutes are designed to absorb the stresses of deployment at terminal velocity.

By manipulating the shape of the body in freefall, a skydiver can generate turns, forward motion, backwards motion, and even lift.

When leaving an aircraft, for a few seconds a skydiver continues to travel forward as well as down, due to the momentum created by the plane's speed (known as "forward throw"). The perception of a change from horizontal to vertical flight is known as the "relative wind", or informally as "being on the hill". In freefall, skydivers generally do not experience a "falling" sensation because the resistance of the air to their body at speeds above about 50 mph (80 km/h) provides some feeling of weight and direction. At normal exit speeds for aircraft (approx 90 mph (140 km/h)) there is little feeling of falling just after exit, but jumping from a balloon or helicopter can create this sensation. Skydivers reach terminal velocity (around 120 mph (190 km/h) for belly to Earth orientations, 150-200 mph (240–320 km/h) for head down orientations) and are no longer accelerating towards the ground. At this point the sensation is as of a forceful wind.

Many people make their first jump with an experienced and trained instructor – this type of skydive may be in the form of a tandem skydive. During the tandem jump the instructor is responsible for emergency procedures in the unlikely event that they will be needed, therefore freeing the student to concentrate on learning to skydive. Other training methods include static line, IAD (Instructor Assisted Deployment), and AFF (Accelerated Free fall) also known as Progressive Free-Fall (PFF) in Canada.

Source: http://en.wikipedia.org/wiki/Parachuting
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