Types Parachute

1 types

1.1 round
1.2 cruciform
1.3 annular , pull down apex
1.4 rogallo wing
1.5 ribbon , ring
1.6 ram-air

1.6.1 varieties
1.6.2 general characteristics

types

today s modern parachutes classified 2 categories – ascending , descending canopies. ascending canopies refer paragliders, built ascend , stay aloft long possible. other parachutes, including ram-air non-elliptical, classified descending canopies manufacturers.

some modern parachutes classified semi-rigid wings, maneuverable , can make controlled descent collapse on impact ground.

round

an american paratrooper using mc1-1c series round parachute.

round parachutes purely drag device (that is, unlike ram-air types, provide no lift) , used in military, emergency , cargo applications. have large dome-shaped canopies made single layer of triangular cloth gores. skydivers call them jellyfish chutes because of resemblance marine organisms. modern sport parachutists use type. first round parachutes simple, flat circulars. these parachutes suffered instability caused oscillations. hole in apex helped vent air , reduce oscillations. many military applications adopted conical, i.e., cone-shaped, or parabolic (a flat circular canopy extended skirt) shapes, such united states army t-10 static-line parachute. round parachute no holes in more prone oscillate, , not considered steerable. parachutes have inverted dome-shaped canopies. these used dropping non-human payloads due faster rate of descent.

forward speed (5–13 km/h) , steering can achieved cuts in various sections (gores) across back, or cutting 4 lines in thereby modifying canopy shape allow air escape of canopy, providing limited forward speed. other modifications used cuts in various sections (gores) cause of skirt bow out. turning accomplished forming edges of modifications, giving parachute more speed 1 side of modification other. gives jumpers ability steer parachute (such united states army mc series parachutes), enabling them avoid obstacles , turn wind minimize horizontal speed @ landing.

cruciform

the unique design characteristics of cruciform parachutes decreases oscillation (its user swinging , forth) , violent turns during descent. technology used united states army replaces older t-10 parachutes t-11 parachutes under program called advanced tactical parachute system (atps). atps canopy highly modified version of cross/ cruciform platform , square in appearance. atps system reduce rate of descent 30 percent 21 feet per second (6.4 m/s) 15.75 feet per second (4.80 m/s). t-11 designed have average rate of descent 14% slower t-10d, resulting in lower landing injury rates jumpers. decline in rate of descent reduce impact energy 25% lessen potential injury.

annular , pull down apex

raf typhoon using drogue parachute braking after landing.

a variation on round parachute pull down apex parachute. invented frenchman named pierre-marcel lemoigne, called para-commander canopy in circles, after first model of type. round parachute, suspension lines canopy apex apply load there , pull apex closer load, distorting round shape flattened or lenticular shape.

some designs have fabric removed apex open hole through air can exit, giving canopy annular geometry. have decreased horizontal drag due flatter shape and, when combined rear-facing vents, can have considerable forward speed.

rogallo wing

sport parachuting has experimented rogallo wing, among other shapes , forms. these attempt increase forward speed , reduce landing speed offered other options @ time. ram-air parachute s development , subsequent introduction of sail slider slow deployment reduced level of experimentation in sport parachuting community. parachutes hard build.

ribbon , ring

the mars science laboratory descending under ring parachute.

ribbon , ring parachutes have similarities annular designs. designed deploy @ supersonic speeds. conventional parachute instantly burst upon opening , shredded @ such speeds. ribbon parachutes have ring-shaped canopy, large hole in centre release pressure. ring broken ribbons connected ropes leak air more. these large leaks lower stress on parachute not burst or shred when opens. ribbon parachutes made of kevlar used on nuclear bombs, such b61 , b83.

ram-air

all ram-air parafoils have 2 layers of fabric—top , bottom—connected airfoil-shaped fabric ribs form cells . cells fill high pressure air vents face forward on leading edge of airfoil. fabric shaped , parachute lines trimmed under load such ballooning fabric inflates airfoil shape. airfoil maintained use of fabric one-way valves called airlocks. first ram-air test jump performed united states navy test jumper joe crotwell.

varieties

a united states navy parachute team leap frogs jumper landing square ram-air parachute.

personal ram-air parachutes loosely divided 2 varieties – rectangular or tapered – commonly called squares or ellipticals , respectively. medium-performance canopies (reserve-, base-, canopy formation-, , accuracy-type) rectangular. high-performance, ram-air parachutes have tapered shape leading and/or trailing edges when viewed in plan form, , known ellipticals. taper in leading edge (front), , in trailing edge (tail).

ellipticals used sport parachutists. have smaller, more numerous fabric cells , shallower in profile. canopies can anywhere elliptical highly elliptical, indicating amount of taper in canopy design, indicator of responsiveness of canopy control input given wing loading, , of level of experience required pilot canopy safely.

the rectangular parachute designs tend square, inflatable air mattresses open front ends. safer operate, because less prone dive rapidly relatively small control inputs, flown lower wing loadings per square foot of area, , glide more slowly. typically have lower glide ratio.

wing loading of parachutes measured of aircraft, comparing exit weight area of parachute fabric. typical wing loading students, accuracy competitors, , base jumpers less 5 kg per square meter – 0.3 kilograms per square meter or less. student skydivers fly wing loading below 5 kg per square meter. sport jumpers fly wing loading between 5 , 7 kg per square meter, many interested in performance landings exceed wing loading. professional canopy pilots compete wing loading of 10 on 15 kilograms per square meter. while ram-air parachutes wing loading higher 20 kilograms per square meter have been landed, strictly realm of professional test jumpers.

smaller parachutes tend fly faster same load, , ellipticals respond faster control input. therefore, small, elliptical designs chosen experienced canopy pilots thrilling flying provide. flying fast elliptical requires more skill , experience. fast ellipticals considerably more dangerous land. high-performance elliptical canopies, nuisance malfunctions can more serious square design, , may escalate emergencies. flying highly loaded, elliptical canopies major contributing factor in many skydiving accidents, although advanced training programs helping reduce danger.

high-speed, cross-braced parachutes, such velocity, vx, xaos , sensei, have given birth new branch of sport parachuting called swooping. race course set in landing area expert pilots measure distance able fly past 1.5-metre (4.9 ft) tall entry gate. current world records exceed 180 metres (590 ft).

aspect ratio way measure ram-air parachutes. aspect ratios of parachutes measured same way aircraft wings, comparing span chord. low aspect ratio parachutes, i.e., span 1.8 times chord, limited precision landing competitions. popular precision landing parachutes include jalbert (now naa) para-foils , john eiff s series of challenger classics. while low aspect ratio parachutes tend extremely stable, gentle stall characteristics, suffer steep glide ratios , small tolerance, or sweet spot , timing landing flare.

because of predictable opening characteristics, parachutes medium aspect ratio around 2.1 used reserves, base, , canopy formation competition. medium aspect ratio parachutes have 7 cells.

high aspect ratio parachutes have flattest glide , largest tolerance timing landing flare, least predictable openings. aspect ratio of 2.7 upper limit parachutes. high aspect ratio canopies typically have 9 or more cells. reserve ram-air parachutes of square variety, because of greater reliability, , less-demanding handling characteristics.

general characteristics

roadside chai shop made of old parachute in ladkah, india.

main parachutes used skydivers today designed open softly. overly rapid deployment problem ram-air designs. primary innovation slows deployment of ram-air canopy slider; small rectangular piece of fabric grommet near each corner. 4 collections of lines go through grommets risers (risers strips of webbing joining harness , rigging lines of parachute). during deployment, slider slides down canopy above risers. slider slowed air resistance descends , reduces rate @ lines can spread. reduces speed @ canopy can open , inflate.

at same time, overall design of parachute still has significant influence on deployment speed. modern sport parachutes deployment speeds vary considerably. modern parachutes open comfortably, individual skydivers may prefer harsher deployment.

the deployment process inherently chaotic. rapid deployments can still occur well-behaved canopies. on rare occasions deployment can rapid jumper suffers bruising, injury, or death. reducing amount of fabric decreases air resistance. can done making slider smaller, inserting mesh panel, or cutting hole in slider.