3-ring release system

Last updated
Releasing 3-ring 3Ring release animation.gif
Releasing 3-ring

The 3-ring release system is a parachute component that is widely used by sport skydivers and military freefall parachutists to attach the two risers of a main parachute to the harness that bears the load under the parachute.

Contents

Invented in its original large ring form by Bill Booth, [1] and subsequently scaled down for thinner Type 17 webbing risers [2] the three-ring system allows a skydiver to quickly cut-away a malfunctioning main parachute with a single motion. Skydivers usually need to do this quickly during emergencies in which they need to deploy a reserve parachute. The three-ring system is simple, inexpensive, reliable, and requires fewer operations than earlier parachute release systems while reducing the physical force needed.

The large bottom ring is securely attached to the skydiver's harness, the middle ring is securely attached to the end of the parachute riser, and the small ring is securely attached to the parachute riser above the middle ring. The middle ring is passed through the large ring and looped upwards; the small ring is then passed through the middle ring and looped upwards. Continuing in the same manner, a cord loop is passed through the small ring, loop upwards, and finally passes through a grommet to the opposing side of the parachute riser. A semi-rigid cable attached to a release handle then passes through this loop, securing the loop. Releasing the cord loop by removing the cable with a tug causes the three-ring system to cascade free and quickly disconnect the riser from the harness.

Each ring in the series multiplies the mechanical advantage [3] of the loop of cord that is held in place by the semi-rigid cable (a Lolon-F or Teflon impregnated plastic coated steel cable, [4] depending on manufacturer).

Variations

There are a few different variations of the 3-ring system. The original 3-ring release from the late 1970s is now known as large 3-rings. A version using smaller rings (mini rings) was introduced in the 1980s. The reasons for the development of the mini ring system and the associated smaller risers were mostly aesthetic; the mini rings do not increase safety but actually reduce the mechanical advantage inherent in the system thereby increasing the pull force a jumper must apply to cut-away. Tandem systems still use rings that are even larger than the original rings, and some tandem rigs even use four rings (e.g., Advance Tandem by Basik). Other variations have placed the rings under the risers facing back instead of forward of the risers facing front or varied the geometry of the rings for example using an elongated middle ring [5] for a claimed improvement in mechanical advantage on Aerodyne's miniforce system.

Safety concerns

Front and side views of a 3-ring (mini rings) release system on a single riser of a packed main parachute 3ring.png
Front and side views of a 3-ring (mini rings) release system on a single riser of a packed main parachute

Since the introduction of the 3-ring system, variations in the design have raised safety concerns. For example, the move to mini rings and mini risers caused riser failures on some designs [6] until riser strength was improved. The failure of some manufacturers to include stiff riser inserts and other hard housing cable guides to allow the free movement of the cutaway cable when risers and webbing are twisted has caused difficulty in cutting away from malfunctions with riser twists or harness deformations. [7] The tolerance in the manufacture of the fabric risers and their connection to the rings is critical in maintaining the mechanical advantage of the 3-ring system and this has been compromised in some designs. Reversed risers placing the rings under the risers has prevented the rings moving freely and releasing under some cutaway scenarios. Replacement of the Lolon-F coating with Teflon impregnated compounds has caused both cracking [8] and cable stripping [9] [10] [11] problems.

Maintenance

Regular maintenance of the 3-ring system and risers is essential. [12] [13] Manufacturers recommend that the risers be disconnected from the harness and flexed, the rings should be checked for cracks or corrosion and the cable should be removed from the housing, cleaned and lubricated, typically with silicone based lubricant.

Related Research Articles

<span class="mw-page-title-main">BASE jumping</span> Sport of jumping from fixed objects using a parachute

BASE jumping is the recreational sport of jumping from fixed objects, using a parachute to descend safely to the ground. "BASE" is an acronym that stands for four categories of fixed objects from which one can jump: buildings, antennae, spans (bridges), and earth (cliffs). Participants exit from a fixed object such as a cliff, and after an optional freefall delay, deploy a parachute to slow their descent and land. A popular form of BASE jumping is wingsuit BASE jumping.

<span class="mw-page-title-main">Bungee jumping</span> Activity that involves jumping from a tall structure while connected to a large elastic cord

Bungee jumping, also spelled bungy jumping, is an activity that involves a person jumping from a great height while connected to a large elastic cord. The launching pad is usually erected on a tall structure such as a building or crane, a bridge across a deep ravine, or on a natural geographic feature such as a cliff. It is also possible to jump from a type of aircraft that has the ability to hover above the ground, such as a hot-air-balloon or helicopter. The thrill comes from the free-falling and the rebound. When the person jumps, the cord stretches and the jumper flies upwards again as the cord recoils, and continues to oscillate up and down until all the kinetic energy is dissipated.

<span class="mw-page-title-main">Parachute</span> Device used to slow the motion of an object through an atmosphere

A parachute is a device used to slow the motion of an object through an atmosphere by creating drag or, in a ram-air parachute, aerodynamic lift. A major application is to support people, for recreation or as a safety device for aviators, who can exit from an aircraft at height and descend safely to earth.

<span class="mw-page-title-main">Paragliding</span> Soaring with a paraglider

Paragliding is the recreational and competitive adventure sport of flying paragliders: lightweight, free-flying, foot-launched glider aircraft with no rigid primary structure. The pilot sits in a harness or in a cocoon-like 'pod' suspended below a fabric wing. Wing shape is maintained by the suspension lines, the pressure of air entering vents in the front of the wing, and the aerodynamic forces of the air flowing over the outside.

<span class="mw-page-title-main">Compound bow</span> Type of bow for archery

In modern archery, a compound bow is a bow that uses a levering system, usually of cables and pulleys, to bend the limbs. The compound bow was first developed in 1966 by Holless Wilbur Allen in North Kansas City, Missouri, and a US patent was granted in 1969. Compound bows are widely used in target practice and hunting.

<span class="mw-page-title-main">Skysurfing</span> Skydiving with board attached to feet for aerial surfing

Sky surfing is a type of skydiving and extreme sport in which the skydiver wears a custom skysurf board attached to the feet and performs surfing-style aerobatics during freefall.

<span class="mw-page-title-main">Bill Booth</span> American actor

Bill Booth is an American engineer, inventor, and entrepreneur in the skydiving equipment manufacturing industry. His invention of the 3-ring release safety device has enhanced skydiving safety. He founded the companies United Parachute Technologies and Complete Parachute Solutions, which had 150 employees as of 2015.

<span class="mw-page-title-main">Prusik knot</span> Type of knot

A Prusik is a friction hitch or knot used to attach a loop of cord around a rope, applied in climbing, canyoneering, mountaineering, caving, rope rescue, ziplining, and by arborists. The term Prusik is a name for both the loops of cord used to tie the hitch and the hitch itself, and the verb is "to prusik". More casually, the term is used for any friction hitch or device that can grab a rope. Due to the pronunciation, the word is often misspelled Prussik, Prussick, or Prussic.

<span class="mw-page-title-main">Malfunction (parachuting)</span>

A malfunction is a partial or total failure of a parachuting device to operate as intended. Malfunctions may require a skydiver to cut away their main parachute and deploy the reserve parachute.

<span class="mw-page-title-main">Static line</span> Cord for automatically opening a parachute

A static line is a fixed cord attached to a large, stable object. It is used to open parachutes automatically for paratroopers and novice parachutists.

<span class="mw-page-title-main">Pilot chute</span> Type of parachute

A pilot chute is a small auxiliary parachute used to deploy the main or reserve parachute. The pilot chute is connected by a bridle to the deployment bag containing the parachute. Pilot chutes are a critical component of all modern skydiving and BASE jumping gear. Pilot chutes are also used as a component of spacecraft such as NASA's Orion.

Cut-away is a skydiving term referring to disconnecting the main parachute from the harness-container in case of a malfunction in preparation for opening the reserve parachute. The 3-ring release system on parachutes allows a rapid cut-away in the event of an emergency.

<span class="mw-page-title-main">Reserve static line</span>

A reserve static line, occasionally called a Stevens Lanyard or Stevens Release, is a device that automatically opens the reserve parachute container when the main parachute is cut-away. The RSL is a lanyard connecting one or both of the main parachute risers to the reserve ripcord.

<span class="mw-page-title-main">Sidemount diving</span> Diving using equipment configuration where scuba sets are clipped to the divers sides

Sidemount is a scuba diving equipment configuration which has scuba sets mounted alongside the diver, below the shoulders and along the hips, instead of on the back of the diver. It originated as a configuration for advanced cave diving, as it facilitates penetration of tight sections of cave, allows easy access to cylinder valves, provides easy and reliable gas redundancy, and tanks can be easily removed when necessary. These benefits for operating in confined spaces were also recognized by divers who conducted technical wreck diving penetrations.

The death of Stephen Hilder, aged 20, occurred on 4 July 2003 at Hibaldstow Airfield, England, in an incident in which Hilder fell 4,000 metres (13,000 ft) to his death when, during a 3-person team skydive, both his main and reserve parachutes failed. The investigation into the death, "unique in British crime history", revealed expert-level tampering with both canopies, but failed to determine whether the incident was murder or suicide.

<span class="mw-page-title-main">Banzai skydiving</span> Rumored form of skydiving

Banzai skydiving is a rumored form of skydiving in which the skydiver throws their parachute out the airplane door, waits, and then jumps after it. To be successful, the skydiver must catch the parachute, secure it, and glide to the projected landing zone. There is no known, credible evidence that a banzai skydive has ever really occurred according to its definition.

<span class="mw-page-title-main">Parachuting</span> Action sport of exiting an aircraft and returning to Earth using a parachute

Parachuting and skydiving is a method of transiting from a high point in an atmosphere to the ground or ocean surface with the aid of gravity, involving the control of speed during the descent using a parachute or parachutes.

A ripcord is a part of a skydiving harness-container system; a handle attached to a steel cable ending in a closing pin. The pin keeps the container closed and keeps the spring-loaded pilot chute inside. When the ripcord is pulled, the container is opened and the pilot chute is released, opening the parachute. On tandem systems the ripcord releases the 3-ring release system anchoring the bridle to the harness-container, allowing the parachute to open.

Firebird USA LLC is an American parachute manufacturer based in Eloy, Arizona. The company also has locations in Germany, Sri Lanka, and the Czech Republic, and was formerly based in Füssen and Bitburg, Germany. The company specializes in the design and manufacture of parachutes and at one time also constructed paragliders and parafoil kites.

A main assisted reserve deployment (MARD) system is a skydiving safety device for parachute systems. While there are many variations, the operation and intended outcome for each is the same: open the reserve parachute container and extract the reserve parachute's deployment bag using the jettisoned main canopy. A MARD builds upon how a reserve static line (RSL) safety device works and in most circumstances, MARDs incorporate an RSL.

References

  1. ↑ "Patent US4337913 -Means for releasably attaching strands - Google Patents". 1978-04-11. Retrieved 2013-11-13.
  2. ↑ "Do Skydivers Care About Safety". Drop Zone. 2003-08-17. Retrieved 2022-08-14.
  3. ↑ "Jump Shack Online". Jumpshack.com. 1996-10-08. Archived from the original on 2016-03-04. Retrieved 2013-11-13.
  4. ↑ "Jump Shack Online". Jumpshack.com. Archived from the original on 2016-03-04. Retrieved 2013-11-13.
  5. ↑ "Re-designing the three-ring release system" (PDF). Archived from the original (PDF) on 2016-03-04. Retrieved 2012-11-30.
  6. ↑ "Jump Shack Online". Jumpshack.com. 1997-09-17. Archived from the original on 2016-03-04. Retrieved 2013-11-13.
  7. ↑ Mike, Gruwell (n.d.). "Hard Housings in Main Risers not Fool-Proof" (PDF). Skydiver. Archived (PDF) from the original on 2022-06-09.
  8. ↑ "cutaway_cables". UK-Skydiver. Archived from the original on 2018-01-30. Retrieved 2022-04-14.[ dead link ]
  9. ↑ "Unknown". DropZone. n.d. Archived from the original on 2016-10-13. Retrieved 2016-10-12.
  10. ↑ "Unknown". DropZone. n.d. Archived from the original on 2016-10-13. Retrieved 2016-10-12.
  11. ↑ "Attachment". DropZone. n.d. Archived from the original on 2016-10-13.
  12. ↑ "3-Ring Release Periodic Maintenance & Mini 3-ring Deformation". Australian Parachute Federation. 1986-11-01. Archived from the original on 2022-03-26. Retrieved 2022-04-14.
  13. ↑ "- YouTube". YouTube . Archived from the original on 2020-02-29. Retrieved 2019-06-13.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.