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Skydiving FAQ:
About modern "ram air" parachutes


Parachuting photos and FAQs (click on an image)

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Helmets

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Jumpsuits

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Altitude, Speed

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Safety

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Parachutes

 

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My PD Sabre parachute.

Who invented the ram air parachute?

The inventor most credited with refining the concept behind a modern, multi-celled, rectangular, gliding parafoil was Domina Jalbert, who patented his parafoil design in 1966.  Although other inventors experimented with gliding parachute designs before and after Jalbert, his parafoil was essentially the key to modern "ram air" parachute design, and the beginning of a new era in sport parachuting.  By the late 1970s, ram air parachutes were rapidly displacing round parachutes.

Do people still use round parachutes?

Today, insofar as sport skydiving is concerned, round parachutes are a thing of the past.  However, they continue to be used in many other applications including military applications (paratroops, ejection seats, cargo, drogue chutes) and certain civilian applications (single parachute pilot emergency rigs, some continued use as skydive reserve parachutes, parasails, cargo, space shuttle booster recovery, small aircraft recovery systems).

The above ram air parachute design (the PD Sabre, by Performance Designs) debuted in 1989.   For many years it set the standard for its class of sport parachute.  It has since been upstaged by even more advanced, high-performance designs capable of very high wing loadings, and incredible speeds & maneuverability. 

How controllable are ram air parachutes?

Very.  They are basically highly controllable gliders. Utilizing a set of left and right steering lines & toggles, (which work similar to aircraft elevon controls; in this case part air brake, part elevator when activated simultaneously) these parachutes can be flown with precision.  Even an average skydiver/canopy pilot can consistently land within yards of a pre-selected point.   Experienced, current canopy pilots can touch down within feet, even inches, (even millimeters for competition "accuracy" canopies) of their selected landing spot.  

How soft are the landings?

Pretty much as soft as you want them to be.  Sport skydivers don't even use "jump boots" anymore.  In fact, when the landing field is conducive to such (grassy, or a beach), some skydivers go barefoot.

How fast do ram air parachutes fly?

Canopy airspeeds vary according to the canopy design, size, and the weight of the jumper.  The average novice ram air canopy & jumper combination has a forward airspeed of around 15mph in level flight; around double that (or much more) in an induced dive or spin.

What are parachutes made of?

The fabric used in most parachutes today is a special type of "rip-stop" nylon that uses "zero porosity" ("ZP") technology.  The special "rip stop" weave pattern greatly counters the tendency for a rip to enlarge.   Additionally, the nylon is specially treated to prevent the passage of air through its skin (thus "zero porosity").  This "ZP" treatment significantly enhances the canopy's flight characteristics, resulting in longer fabric life, better glide ratio and extremely soft landings.  All canopies today use "rip-stop" technology, most also use "ZP" technology.

How big are modern parachutes?

To accommodate varying jumper weights, experience levels & desired flight characteristics, modern sport parachutes are offered in a very wide variety of models & sizes.  Student jumpers may use canopies measuring up to around 300 square feet, while highly experienced jumpers may use high performance canopies measuring less than 100 square feet.

Off-site reading:

The Jalbert Parafoil Patent