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artistcalledian

Difference from a 280 down to a 170?

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This is something that was clarified when our team attended PD rep training as part of our sponsorship. PD state that a high proportion of landing injuries are sustained by in-experienced jumpers on canopies that have been recommended to them by instructors based on a (relatively) low wing-loading....1:1 is not that much but the 120lb jumper will experience a dramatic increase in performance as a result of the shorter lines...the canopy will respond (i.e turn) MUCH faster and more steeply. Not trying to scare you here, just spread awareness. Now, this is also no dis to any instructors out there still dispensing advice to light AFF grads regarding appropriate canopy size......I had 9000 jumps at the time(1200 AFF) and I replied that the performance in the 2 scenarios would be identical !!:S

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If you do buy the 170, be aware that many DZ's in the US will not allow you to jump it. I can't speak for the UK, though.

The USPA recomends the folloing maximum wingloadings:

A license—1.0 psf maximum
B license—1.0 psf maximum
C license—1.2 psf maximum
D license—1.4 psf maximum


In the US, a C licence requires 200 jumps at least. A D license requires 500 jumps.

So, in essense - your instructors are recomending you buy as a first canopy what USPA recomends as MAXIMUM for someone with 300 jumps.

Again, I'd suggest you may want to find someone different to take your advice from.

_Am
__

You put the fun in "funnel" - craichead.

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Different (the 120 sq. ft. will be have faster turn response and quicker dynamic stall response). That's per the SIM.

As for the "why", the SIM leaves that out. Hazarding a guess, though, I'm going to say that it relates to the aerodynamic nature of the wing: at the speeds that we're travelling at, we need a certain amount of wing surface to generate the same amount of lift, and that amount isn't directly proportionate to the drag. In other words, is it that the smaller jumper has a greater proportionate drag co-efficient?

Just a guess.

P.S. I just read the answer that someone else posted before me. The lines are shorter. That makes sense.

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I'm a little surprised you're buying a brand new main for your first canopy at all, but that's your business. Many people will go through one or two second hand canopies before settling in on a canopy type and size they really want, based on their experience from a few years' jumping.

But hopefully you should be able to get Aerodyne change your order to a 190. And because Aerodyne charges the same for their canoies regardless of size, it shouldn't cost you any more (unless they've already started cutting material for the 170), OR effect the instructor's profit margin on his sale to you. By the way the Pilot's a great canopy, but you'll enjoy it more if it's better sized for your experience. No canopy is fun if you get hurt.

Your humble servant.....Professor Gravity !

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I jump a Pilot 150 and I weigh about 180 out the door. I'm loading it around 1.2:1. I have close to 300 jumps, with about 70 on this canopy. At this wing-loading, much less at 1.3 or more, you have to be flying your canopy confidently all the way to the ground. Everything from the turns to the landings are going to be completely different from the 280. Think of a toggle turn where you can't pull the toggle past your elbow, and after a 360 your legs start to hurt. In landing you have to be able to judge your altitude accurately and quickly and account for your forward speed at the same time. It's certainly not a cross-braced hankerchief, but it is beginning to be in the realm of high-performance flight. I would not have been comfortable flying this at 100 jumps. Things just happen faster, and there's more to think about. This is something you learn to handle through experience. So here's my opinion. And it's just my opinion. You need to be comfortable under whatever canopy you are flying. You need to be confident, not wondering as you make your final "Am I gonna biff it? Am I gonna flare right?" You need to be able to have a certain percentage of these factors down-pat as instincts, so that your mind can focus on other things, like traffic. Hopefully your instructors will get you ready before letting you fly this canopy. But if YOU are not comfortable, the final veto power lies in your hands. If YOU feel like the 190 is what you want instead, that's your choice. It's your money, and if you call Aerodyne at this point and tell them the deal, I'd bet there would be no problem in changing it. Remember, this is YOUR life. You have the right to be as safe and cautious and take as much time as you want, so that you can assure that you will have time in your future.

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Enough has been said on the wingloading question...

Just be aware that sport canopies handle & fly very different to student ones - I didn't notice much difference between a 280 and 230 student but when i moved to a pilot 210... let's just say the beetle-to-sports-car analogy is very apt. I'd also gotten used to hard turning the student ones and got quite a fright doing the same thing on the pilot! Whatever size you end up jumping off student canopies - just make sure you take it slow.

Oh, and find out about any differences. I panicked for a second because i couldn't peel the toggles off the (non-existent) velcro...:P
Skydiving: wasting fossil fuels just for fun.

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>they hadn't told me this, but they decided that they will downsize
>me on my consol jumps and keep monitoring my performance untill
>mine turns up...

Sounds like a good plan. Before you go to the next size smaller (i.e. 220 to 190) I would recommend you be able to do the following on the larger canopy:

-flat turn 90 degrees at 50 feet
-flare turn at least 45 degrees
-land crosswind and in no wind
-land reliably within a 10 meter circle
-initiate a high performance landing with double front risers
-land on slight uphills and downhills
-land with rear risers

Once you can do all that on your current canopy you're probably ready to downsize. It can be a mistake to downsize sooner, because once you downsize you'll be afraid to do any of the above and you'll never learn how to fly it.

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i rang my instructor earlier, and he set my mind at rest... but now i've read some more, i'm thinking that maybe a 190 will be better in the long run. I've never thought of the canopy bit as the main part of the dive, i see it as the bit that gets me back on the floor so i can go and freefall again, so i don't really want a hyper peformance canopy as its going to be wasted on me (and probably kill me)
________________________________________
drive it like you stole it and f*ck the police

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The other thing that i would say is that CCI at langer may not let you jump this size of canopy Cos. The instuctors who say you are ready for it can only recommend this to him, as he has overall control of the safety of the people who jump at his dropzone. Would say that you should also speak to him:|

Billy-Sonic Haggis Flickr-Fun


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thanks for all the advice people

i put he CCI in a wheelchair 3 weeks ago :o he came down with me on a level 7 jump, i span out of control and he came in to stop my spin and dislocated his shoulder, then broke his foot on landing. I bought him a bottle of brandy to say sorry. I saw him last saturday for the first time since the accident, said how sorry i was and he said it is not my fault at all...just one of those things that happens to students and its part of the risk of the job.

Shall i put my canopy skills into perspective for you all ? on my first consol jump, it was strong wind and i forgot any kind of landing pattern... i was over the centre of the airfield at 2,500 feet directly above where i wanted to land... i just sat facing into wind going backwards from 2,500 feet untill i landed. i landed so far from the clubhouse, they came out in a truck to give me a lift and save me the half mile walk in :$ i think a 168 might be just a little too much for me
________________________________________
drive it like you stole it and f*ck the police

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I did the same (288 going to 170). Take the advice and transition 288->230->190->170 like I did. (Assuming you are about 170ish pounds exit weight or lighter that is)

I've been on 170 for the last 77 jumps now and going to keep doing it for at least another hundred or so.

A 170 can spin dangerously into linetwists if you yank a toggle suddenly. I was easily able to spin my 190 into linetwists once just by yanking toggles. Be careful. Listen to your instructors.

Edit: I noticed you'd be 1.3 wingload.... Who recommended the 170 to you? If it was your instructor that is advising 170 being okay for you, I'd suggest asking for a safer recommendation and going 210 instead which would be more in your territory.
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On my AFF i used a 280 canopy, nice and slow (at this stage, i just want to do a few turns and get down safe) i've ordered an Aerodyne pilot 170 as my main... what will the difference in speed and handling be like compared to my AFF kit?

on the 280, i could pull a toggle down as far as possible to turn and it would just lumber round in a nice, slow turn. Can i do the same on a 170?

what will the speed be like coming in to land? on the 280 in even moderate wind i'd have virtually no forward movement :$ so i could concentrate on when to flair (still end up on my arse sometimes B|)

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erm.... i'm 190 lbs without gear on !

Wingload calculations is based on exit weight (wearing all gear, including helmet, altimeter, rig, etc). I am 163lbs naked but am 191lbs exit weight.

You'd be 215-220 lbs exit weight, which warrants a 210 or 220 canopy. This would be the recommendation of most pople. Most recommend 1 pound for every square feet of canopy, a 1:1 wingload, as the first canopy. Wing load is calculated by total exit weight divided by the size of your canopy. Math indicates you will be a 1.3 wingload at 190 without gear which means 215-220 exit weight with all gear.

It does vary a bit - a 1.1 WL under a heavy jumper on a big canopy is reported to be safer than 0.9 WL on a light jumper under a tiny canopy, so there's a bit of fudge there, but 1.3 is an advanced wingloading that often leads to severe injuries.

(If you HAD to be aggressive, 190 might be okay if you jumped rental canopies for several dozens of jumps first -- that's still a wingload of 1.15 and plenty exciting much like my Sabre 170 at 1.1 wingload -- and I considered that aggressive for myself at 59 jumps)

Now, my advice may be total crapshoot, but you should talk to your instructors, and more than one. Take the most conservative recommendation. I know some instructors wrongly recommend wingload 1.3, I wouldn't start that aggressive...

I'm just an intermediate jumper, not an instructor, not a coach, but 1.3 is really aggressive...

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I would check out undet the safety section of this very web site... there is an article about things you should be able to accomplish before downsizing your canopy... check it out learn the skills, love the skills.
Divot your source for all things Hillbilly.
Anvil Brother 84
SCR 14192

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erm.... i'm 190 lbs without gear on !



roger that... so now add 20 pounds for things like your container, reserve, shoes,:o helmet:|
instruments, and clothing......

and then factor in not only your relative lack of "time under canopy" but also your fewer than 2 dozen landings,,, and you'd likely agree that 169 ft2 is a bit too small....... hell, you need to be using a 210 or so.....:|:) their abilities, and superimposing them onto you...>:( be careful there....[:/]
you also point out in a post here that you view the canopy descent as " the way to get back on the ground so that you can make another freefall..."
Please generate a greater respect for the importance and significance of the parachute portion of this sport..... That will certainly enhance your longevity in the sport and also guard you from an early departure from skydiving, due to a debilitating injury from this "less significant" portion
of any of your upcoming skydives.[:/]
Upsize, Downsize, Why not just find and then stick with the Right size..?.. ( which in my mind, at your experience level really should not higher than 1: 1 )

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Shall i put my canopy skills into perspective for you all ?
...
i just sat facing into wind going backwards from 2,500 feet untill i landed.


Uhm.. That sounds more like a wind problem than a canopy control problem to me ;)

As for the classic "Ask your instructor"-advice, I have personally expanded that to "Ask any instructor you can find and keep bugging them with questions for months". That will leave you able to make an informed decision. I am ~240 out the door and I was recommended anything from 230 to 190. I was jumping Manta 288 and Falcon 300 as a student. I ended up demoing a Triathlon 210 recommended to me by an instructor and rigger. Before I did I asked another instructor if he was comfortable with me jumping this rig given that exit weight. I ended up buying another canopy but stuck with the size as I quite liked it.
HF #682, Team Dirty Sanchez #227
“I simply hate, detest, loathe, despise, and abhor redundancy.”
- Not quite Oscar Wilde...

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