Binary93

Weird, I contacted them multiple times and they responded within 30 minutes or so. I recommend using [email protected], not sure about the contact form on the website.

This definitely poses additional risk and is something to be aware of when jumping. Make sure to have your leg straps tight to decrease the risk of accidental shackle release and it's also good that your fellow jumpers are aware of this.

These are both quite bigger than the sizing chart recommends (J4K is 176-190 reserve and 190 main). Since you say J4 I assume it's a pre-K series (~20+ years old) so it might have stretched somewhat, but that pretty much explains why it seems very tightly packed. I've had 170/180 in my J1 (which is rated for 150/143), but it has some stretch and doesn't seem overstuffed. Deployed the reserve once without any issues, but I wouldn't blindly recommend it.

Altimeters can be worn on the forearm so you can more easily see them under canopy, especially for swooping for example. This is also a point for analog vs digital display (regardless of what's inside), digital is required for swooping as it offers more precision than a gauge. Regarding question #2, discuss it with your instructor. Audible should not be your main source of altitide awareness, it can and will fail. In my humble opinion, you should start using one only once you can be fully comfortable without it and pull at the intended altitude.

Not that you can what? https://www.facebook.com/watch/?v=604223603652353 (joke)

As I understand it, the point of that is not in the slider (nothing special there) but in exposing the center cell and rolling/tucking in others. This will cause the center cell to inflate first which will promote more on-heading opening. I've had this problem (video below) where half of my canopy would inflate before the other side (and even before the center cell) which essentially "breaks" the canopy in half and causes it to spin. Doing what Brian showed in the video helped me solve it. Btw, FluidWings recommends this when packing all their canopies.

In this video (linked at 11m34s) Colin suggests treating main vectran lines with PTFE spray. On one hand it seems logical to me that it would save some life on the lines. On the other hand, I can imagine it altering the friction forces exerted by the slider so not sure if it could lead to hard(er) openings? Is this something that's commonly done? What do you all think about this?

You use USB to connect to it. It shows as a mass storage device (like a usb flash drive). In there you will find a config file where you can configure what to report in what way (glide in your example), min and max glide for which it will produce a sound, etc. You can find all the details here: http://flysight.ca/wiki/index.php?title=Main_Page

Fair point, and I agree. I know there are folks around here who did lots of both design/development and testing of different canopies (also for cargo IIRC), so I thought they might have some insight and data regarding this. I'm hoping for some data and experience here :) "No" is also a valid answer (i.e. size doesn't affect the opening characteristics in a predictable way), but as I said, it would be awesome if there was some data or experience supporting it.

Had a discussion with a friend, haven't done any testing and didn't find any information on this so asking here. When a same person jumps the same canopy of two different sizes (say 170ft and 100ft), does one (as a rule) open faster/slower/harder/softer/other than the other? And if so, how would this difference be compared to the differences in openings for two different canopies of the same size (e.g. pulse and katana)? We can assume packing is identical, etc. Not asking about the skill required to fly the openings (harness, etc.) but only about the speed/strength of the opening.

Students going to their first jump (not all of them are on SOS) might need to execute EPs on their first jump (or first few jumps).

Thanks dudeman, I generally agree with everything you said. However, while I think that more training is THE solution, I'm not sure it's the one that can be realistically implemented. How much training does a student have before going for their first jump? Do you think this is enough to develop such muscle memory that will override the instincts you've built your whole life? Do you think it's realistic to expect students to spend months of rehearsing EPs before they make their first jump? I know this is what FJC looked like in the old times (spending months practicing EPs, jumping into sand to practice PLF, etc.) but I doubt that's something that we could go back to now.

Here's a relevant thread linked to a post cherry-picked to support my argument (along with those following it) :)

True, but not finding the reserve handle after pulling the cutaway handle is in most cases mitigated by having RSL. Skipping the cutaway because you looked at the reserve handle before can cause two-out. I'm talking here only about students, FJC, etc. If you have loads of experience, you can triage problems better, have better awareness and decide what's right for you with the gear you're using and a situation you're in.

From my reasoning, of those who practice it like you've initially described (...grab red, look silver, peel pull red...) I think most will not be doing that because it's unnatural to do it. People have a strong instinct to look and do stuff in sync and that instinct is reinforced each day many times through random things you're doing. The logic behind practicing "...look red, peel pull red, look silver..." then is, why would you practice something you'll most likely end up not doing, just practice the thing that's more realistic to execute as practiced. In most cases, you'll have a functioning RSL (a defensive mechanism against not finding the reserve handle later) but looking for reserve handle before pulling the cutaway might cause you make an error of skipping the cutaway (because of the instinct I've mentioned) which is then a whole new problem. This is not a pure random guess (how people execute their EPs) but is based on some experiences/testimonials, though I do not have a concrete study with statistics so let's call it an opinion without a solid ground. It appears Perris is teaching it this way now (based on the information from the other thread).

<sarcasm>Why would you have EPs then? If you make an error requiring EP it just means you need more training, is that what you meant?</sarcasm> Please don't think that you have thought about all the different things and that others are just dumb idiots doing stuff randomly. The procedures are there to reduce user error, which for folks just beginning their journey into the sport is very important because they do not have enough training. I doubt your FJC lasted for months practicing EPs. Everything in skydiving (procedures and gear) follows defensive design because errors can and will happen. Sorry for hogging the thread and for a semi-rant, I'll stop responding to these. If anyone wishes to talk about this further, they can start a new thread with a more appropriate name.

Sure, I'll let them know you disagree with their method. There have also been people doing look, grab, look, grab, peel, pull and ending up with two out (skipping the cutaway). And many are practicing look, grab, look, peel, pull, peel, pull but end up doing something different (like look, grab, pull, look, grab, pull) in the EP because it's unnatural and you tend to look and do stuff in sync which is a reflex that can kick in in stressful situations. You can practice a lot, but you still look for the fork, pick up the fork, look for the knife, pick up the knife when you eat lunch every day. No method is perfect, and the best one is the one he is taught by the instructors and which he practices.

With all due respect @CoolBeans, I would really suggest you try to be more humble. I understand you have the best intentions giving such advices, but you are not in any way competent to do so. And please don't take this personally, I understand you mean well. I was taught the exact same procedure that David described (look, grab, pull, look grab, pull). We can discuss the differences and exchange opinions but it ultimately comes down to the fact that EPs are taught with different variations and the BEST procedure is the one you practiced (be it pull-look, look-pull or the single-handed version). @David Wang, for EPs and related topics, talk to your instructors. Please don't take advice from the internet for granted, noone here knows you personally. Talk to your instructors, share your thoughts and concerns, go through procedures with them and then practice them the way they show you.

There's actually two Windy apps and I like to use both of them. The blue Windy (when paid) gives you wind and precipitation from multiple models on a single chart. The red Windy has nice meteogram view so you can see clouds over altitude. It can also show you cameras on some places so you can see what the sky looks like semi-real-time. Weather & Radar is good for checking the clouds on the map to know what's the next few hours gonna look like. SpotAssist is great to check wind speed/direction over altitude.

Posting these from the facebook post so they get saved here in the thread rather than get lost on facebook. Disclaimer: I did not invent/try/see anyone try this exact method.

Also, might want to check this one: https://www.performancedesigns.com/compare4

Thanks Matija, I've seen this one but it's a version with the tape at the bottom, while apparently there's a version with a fingertrap at the bottom as well.

I completely agree, but from the comments, it looks like a systematic issue. I myself don't have a problem with this (yet?) but I'm hoping to learn how this sleeve is done properly. From what I understand, the bottom of the line (hma/vectran) is passed through a larger spectra line. How is the spectra properly secured? What are the dangers of this modification? Apparently, some folks used some sort of adhesive tape at the bottom, but that ended up causing a fatality. Some fingertrapping at the slinks side is also mentioned, but I'm not sure how exactly that's done.