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FastRon

Modern canopies

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I'm giving really serious thought to resuming skydiving on my 60th b-day after 31 years. Last jumps were on old Strato Star (shortlined with slider.) Q.- Do newer canopies of say 180sq. ft. of new material have slower descent rates? higher glide ratios? What are some of the other differences?
Will I have to tandem (seems 'clunky'...) go back to static lines or what? Nearest drop zones are Snohomish, and Shelton (Kaposin folks) in Washington.

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I'm giving really serious thought to resuming skydiving on my 60th b-day after 31 years. Last jumps were on old Strato Star (shortlined with slider.) Q.- Do newer canopies of say 180sq. ft. of new material have slower descent rates? higher glide ratios? What are some of the other differences?
Will I have to tandem (seems 'clunky'...) go back to static lines or what? Nearest drop zones are Snohomish, and Shelton (Kaposin folks) in Washington.



After such a long break you will want to go back through a full first jump course. I would recommend AFF and as you have previous experience you may be allowed to merge or skip levels.

On a FJC you would start on a student canopy which will really impress you! The flare is very powerful and landings should be very soft. Packing methods and the equipment have changed quite a lot. Even from the 1990's when I first jumped. So now AAD's are commonplace, pilot chute location is typically bottom of container.

I think the equipment is much more reliable than it used to be, however as usual people have found ways to keep the risk up.

Have fun and good luck on your decision.
Experienced jumper - someone who has made mistakes more often than I have and lived.

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Your fastest route back to regular jumping will be the AFF program. You'll have to sit through the majority of the first jump course, but you'll need it to remind you of the 30 year old stuff that still applies, and learn the new stuff that's come along. You'll also learn the procedures for the DZ and the first AFF jump.

The jump will involve a freefall from 13k with two instructors maintaining grips on your harness right from the door. These grips are maintained from exit to opening with actual first jump students, the instructors may choose to release you at some point in freefall.

In terms of equipment, you willl be jumping the DZs student gear while you are jumping with their instructors. The rigs are configured to make it easier for them to do their jobs, and that's what they'll want you to use. Every DZ has a selection of canopy sizes available in their student rigs, and they'll figure out what size works for you at the time of your jump.

Everything beyond that will depend on your performance on that first jump. If you do well, they may cut you loose and clear you to jump solo. If you're rusty, they might want you to make another jump or two with an instructor. Likewise with the gear, what size and type of canopy you end up jumping will depend on the how it goes with the student rig.

Overall, pay a visit to each DZ near you on a Sat or Sun, watch the operation, and speak to the DZO or an instructor about your situation. Pick the DZ that seems to have their shit together, and seems to have the best plan fo attack to get you back in the air.

The good news is that once you learn the new gear and new DZ procedures, skydiving is pretty much the same as it used to be. Of course, most of the staff and fun jumpers weren't alive when you stopped jumping 30 years ago, but that's another story.

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What about going to both places for a day of
watching and listening and see which place
strikes you as the most comfortable to start?

While you're there you can get the details of
how they would want to get you current.

Once you're back in you can jump at both places
see what develops.

Some things have changed over the years.

The airplanes are way better, and squares have
come a long way since the Strato Star days.

Human nature hasn't changed, though.

You still get that feeling when you jump out
into freefall, and the newer jumpers are just
as enthusiastic as always, and people still drink
beer and embellish their stories, and you still
see young guys doing stupid shit to impress
the few girls around :-) :-)

Once you're around every weekend you can
start tuning in to appropriate gear.

I jump at Snohomish so I know they do a good
job of guiding their newer jumpers.

Pitt Meadows just north of the border is also
a really good dropzone, but the dollar has lost
so much value that Canadian prices are way
up there.

Shelton is a really long drive for me so I haven't
been there, but I know people who jump there
and you would be OK there, too.

So really, you can't go wrong at any of those
places.

Skr

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Thanks for the timely replies. B-day is in Sept. so I have a few weeks to check some things out. In reading the forums here- I see swooping etc, Obviously, the new canopies have capabilities far beyond those of early squares (besides better reliability and orderly deployment (lack of line twists were kind of rare w/ my Strato Star)). I understand the wing loading thing, the mystery is the apparent ability of newer (very small), canopies to create lift at speed, and not crush ankles (or worse) on landing. Is it the material, shape, technique, a combination of the above, or maybe portable flux capacitors?

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> portable flux capacitors?

No, they could never get those to work right.

The latest stuff has levitator crystals mixed in
to the coating that makes the canopies zero
porosity.

But even the Strato Star created lift. It's just that
canopy design is one place where gear has really
evolved forward. The new canopies come from a
lot of research, engineering, test jumping and
experience.

Skr

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Hmmm. I once took the "opportunity"? to jump a Strao Flyer- 160 Sq. Ft. I think. (At the time I weighed around 190#) . Fortunately? I landed on a slight downslope, in some nice soft mud. I called it a hard landing- not as bad as a unaltered flat 28' but very solid... What I recall from my Strato Star was not much lift, an unlikely candidate for any swooping- at least the examples of that I've seen on video, and demo jumps at football games. We called "ground effect" the feel of your feet touching any firm surface other than tree limbs or buildings.

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the mystery is the apparent ability of newer (very small), canopies to create lift at speed, and not crush ankles (or worse) on landing.



Reliability:

While some early squares had reliability issues while designs, deployment, and reefing were worked out, later those would be sorted out. A large conservatively designed square using F-111 style material can be one of the most reliable canopies out there. Small modern canopies are LESS reliable. Something that leaves a big square canopy with a little built in turn and easy to kick out line twists, may send a small canopy built for high performance into a sudden spiral towards the ground, pitched pretty much 90 degrees down, with line twists you'll have no time to get out of.


Small canopies:


"Zero porosity" material, with coatings to keep the air in, came along roughly at the start of the 90s. That was one big innovation, which in turn made it possible for designers to then improve aerodynamics.

To oversimplify a bit: Back in the late 80s, a hot shot jumper might get a 170 canopy while others had 200s. But after 300 jumps the porosity would be going up and he'd be landing hard, and he'd only be able to sell the canopy to someone 25 pounds lighter, who could get a little more use out of it.

Zero-p canopies canopies made it possible for a canopy to last 2000 jumps, with some line set changes along the way, and still land reasonably well.

Zero-p isn't supposed to add that much in aerodynamics over absolutely brand new F-111 style material (While the trademarked F-111 is no longer made, we still use the term for all non-coated material that is "zero to 3 cfm" permeability when new). The biggest thing is that F-111 style fabric wears so much quicker.

With zero-p, designers could improve canopies. Lower cell heights, smaller nose openings, less drag. The better the airfoil, the smaller the canopy you could get away with. Design just got less conservative as companies tested what worked in practice. The 3-D design improved to make canopies less lumpy. Computers would help with that. Fabric would be cut to greater accuracy with laser cutters, not manually hot knifing around a metal rib template. Smaller size with the same number of cells effectively put things like ribs closer together, improving the shaping of the canopy.

Also helping reduce drag was newer much thinner line material. The more modern types also hold their dimensions better over time. Smaller, precision designed canopies are in more need of accurate line lengths that don't change over time, to fly properly.

Other little drag saving innovations came along too, like collapsible pilot chutes. No big deal under a big slow canopy; a bigger deal under a small fast canopy.

Designers also realized that "efficiency" didn't mean the best possible glide ratio. In the 80s, companies advertised how good their glide ratio was. Nobody did that later on. They realized we weren't trying to build paragliders to float around at slow speed. (To be fair to paragliders, things are much more complex than that now.)

It was discovered one could trim canopies more nose low to get extra speed, giving up some glide ratio. Despite diving faster for the ground, the extra energy would provide a better flare, planing out better for a nice landing with zero descent rate.

By the mid 90s a typical hot jumper setup would be a Stiletto 120, with a PD-126 reserve.

Jumpers also had to adapt and learn the techniques for flying smaller canopies without killing themselves. (Yeah, we don't always quite have that figured out yet....) What used to be crazy fast is much more manageable now with the right knowledge and training wide spread in the sport, thus bringing down the average size of canopies used across all licensed jumpers.

Doing an accelerated dive before landing became a much more normal thing. Even without being a hard core swooper, a small dive before landing again provides extra energy that can be turned into a flare that takes longer, giving more time to fine tune one's height and descent rate to a softer touchdown.

Then in the late 90s crossbracing came along, again improving aerodynamics. (Aside to experienced jumpers: I'm talking about "effectively" -- not about the Excalibur or Jyro's first experiments.) Extra diagonal reinforcements in cells made the canopy smoother, retaining its designed shape better in the air, without the ribs without lines bulging upwards. And it stiffened the canopy against distortion in turbulence, also keeping the wing flying closer to as-designed.

One can design and fly some pretty small non-crossbraced canopies. E.g., I have a 75 that I occasionally jump, and some jumpers have say 113 square foot reserves, made from F-111 style material. But crossbracing improves the aerodynamics. Crossbracing combined with trimming canopies to dive more steeply for the ground, set off much of the modern swooping revolution.

So zero-p was the big enabler for small canopies, but in the end it is the combination of all these things learned over time that got us to where we are today with tiny canopies.

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And all that shit that we consider "hot / extreme", cry about, bash others about, rant today will be yesterdays news and probably considered "normal" in 30-50 years from now..

Just like the all the stuff from the current past..
"All limits are self imposed." Icarus

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Hello, I am not old but being mindful of the issues based on some research for someone, it appears that the sweet spot for an older skydiver is a wingload of very close to 1 on a very good brand canopy. So if you are scared of swooping and want to maximize safety.... (especially after you're finished re-doing your jumps on student-type wingloadings)

1. Eliminating the "Ankle Crush" factor:
As pchapman explains, modern canopies plane out more easily, the smaller they get, because of their speed. (At least for the sizes currently in common use). But going too small means landing mistakes are even more dangerous. Canopies wingload 0.8 approximately and smaller canopies -- the canopy starts to have the ability to "plane out" -- completely zero vertical velocity. Lighter canopies than approximately 0.7, you will still have some ankle thump factor usually (unless you are really good and aggressive at flare on a new canopy) but it's a lot less than a round. The act of flaring is like trying to tilt the nose upwards on a gliding airplane: It allows you to turn forward velocity into lift (at least until you slow down and you don't have lift anymore) -- that's how airplanes can safely land even when they lost an engine (i.e. glider). Your canopy is lighter than an unpowered metal airplane, and you will much more easily "plane out" on landing. Round canopies were not really gliders back then and didn't have the luxury of the "flare" to zero vertical velocity like a landing glider. Now, once you more heavily load than around 0.7 to 0.8, you can easily completely eliminate vertical velocity, and therefore, eliminate ankle thump given a proper flare in good winds. Yes, smaller canopies makes it even easier, but a mistake flaring under a smaller canopy means big danger, especially if your bones are at risk. Note that new fabric, will plane out better than old fabric. So buying new for your main is a good idea, they land more gentle.

2. Eliminating the "Wind Hold" factor:
Bigger canopies than a wingload of about 1.0, you will be stuck on the ground too often. Big parachutes go slow. You fly backwards during strong winds. You decide to stay on ground. You want to more heavily load to prevent wind holds from happening too often.

3. Eliminating the "Slammo Opening" factor:
Older bodies can't handle explosive openings. Choose a soft-opening brand that's very forgiving of occasional messy pack jobs from random packers. There are many, I've seen Pilot's and Sceptre's open so pillowly-soft and gentle. Just make sure you know to pull a tad higher (i.e. don't do many low 2000ft pulls with them). If buying used, choose an appropriate slider size the factory recommends; some used canopies came with sliders too small for them before manufacturer recommendations changed. (i.e. my Sabre 1, which opens too fast sometimes; I don't recommend them unless you're prepared and don't let inexperienced packers pack them.)

4. Reducing risk of landing errors
Factor 1 and 2 (ankle crush and wind hold factors) tends to recommend smaller canopies. Now you already know more heavily loaded canopies start to become unforgiving of landing mistakes, like improperly-executed low turns. Therefore, you now have to find a compromise loading that's heavily loaded enough to satisfy factors 1 and 2 (ankle crush and wind hold factors), but not too heavily loaded to significantly increase risk of landing mistakes. Therefore you will see a common and good equilibrium modern wingloading of approximately 1.0 for a first canopy -- give or take depending on specifric circumstances.
....

So, if your priority is a good compromise, you will find a wingload factor of around 1.0 (give or take a little bit, depending on wear, brand, body weight, instructor approval, Brian Germain chart, Skydiver Information Manual, etc), brand new, on a pillowy-soft-opening canopy of recommended new-jumper-friendly type, to be roughly a perfect compromise for someone who is worried about being easy on old body and ankles.

Of course, when you start jumping, you will be jumping something really big (i.e. 260 square feet, etc) and will be pretty lightly loaded. It will still have much less ankle thump than any round, and will be comparable to jumping off a chair. If they got good fresher student canopies, on a good day, that are easy to flare, and you are good at distance perception & flare timing, you can still pretty much plane out on jump #1 and pillow soft touch down. (it happens often nowadays at some dropzones with good student canopies now! But there will be those less-good landings that have a bit more thump.) .... But temper your expectations, for now -- be prepared to PLF to save your bones.

That said, you need to make sure you have the strength and make sure you've got strong bones (i.e. don't skimp on your vitamin D and calcium, etc and/or get enough sunlight to get that, if you work a desk job) before you begin jumping.

You MAY still get injured skydiving, but you can LESSEN your risks, especially of major injury, by following a few of these popular (and easy) 1-2-3-4 recommendations.

Yes, you MAY find you want a faster canopy eventually, but for an older skydiver, it's really is best downsize really slowly. Watch your body's ability to tolerate skydiving, and how well you still PLF these days at your age, before making further major gear decisions. Especially if you've got years of family behind you that want to see you stay alive longer. :-)

Lastly, your instructors will be the most important people in it all. Find someone who "understands"; especially at least one of the instructors who's been "there" in the old days, too. Even if he won't be your primary instructor (they're getting rarer and rarer...)

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Thanks much all of you. I can see how it appears to work now. When I was jumping the StratoStar- I weighed about 190. (6'-3", very dense, thus the nickname) Today 210, same height, some say still dense (both definitions I suppose).
Don't know if 5 cells qualify for 'wingloading' but I would then have been at about 1.2. It flared OK, and was way easier to 'fix' long/wrong spots. Small headwinds would land like stepping off a stool. No winds, hot day, way more 'sporty'. I regret we didn't have more film of some of the wrecks we endured.

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In many ways, being out this long you will be getting back in almost from scratch. Take your time, start on the student gear, and work your way into a wing that is suitable for you.

The modern wings are pretty amazing (at all ends of the performance spectrum), and I'm sure you will find a design and size that will make you happy.

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