DaVinciflies

You might not get much respect if you tried to pass yourself off as someone with 6000 jumps like you do on here. Other than that - you're welcome.

Good. That's a start. Do some homework tonight and let us know your revised answer in the morning! (Hint: if any lines other than brake lines are slack during flight you have a problem. Line tension is your very good friend).

It is good to know how your canopy responds on rears with brakes (note the spelling) stowed and unstowed. You can practice both up high. You tell us. What lines are you pulling on in each case (brakes stowed and unstowed)? Where do those lines attach? What is the difference in "control surface" in each case? Does that explain why one is more responsive than the other? I am serious - give it a shot at answering those questions.

+1 Spence, the jumpers you're talking about don't even understand how their gear works, let alone the science behind it. Understanding is the foundation of safety. Too often that understanding is absent these days. I agree. The AFF syllabus is so light on this, it's a joke. And we can't blame the jumpers because nobody tells them how little they know.

Nip positive. No idea who but it gets my vote!

Agreed. Without a nipple it's just another lump of fat. The nipple makes the tit.

Ok - here's my attempt! The stall occurs when there is flow separation from the top skin of the canopy causing chaotic, non-laminar flow and a loss of lift. This can be caused by giving the air flow too abrupt a change in direction to follow along the top skin (like trying to drive around a sharp corner too fast in a car). In a rear riser stall, the pilot pulls down on all the C and D lines deflecting the back half of the canopy downwards. At a certain point the airflow over the top of the canopy can no longer follow this change in angle between the front and back halves of the canopy and flow separation occurs at the back half. The back half of the cells cease to fly and the stall occurs. This can occur quite abruptly right across the wing and you lose the lift from half your canopy. In a toggle stall, the pilot only deflects the very back of the more outboard cells so when a stall occurs they stop flying while the center cells continue to create lift, hence the reason why the ends of the canopy deflect backwards.

When you say "causes it" what exactly is "it"? Are you asking why it is more sudden, or why it occurs with less input or at a higher speed? Not being difficult here - just trying to define exactly your question.

This. Soft landings involve: a) eliminating/reducing vertical speed as much as possible b) eliminating/reducing horizontal groundspeed as far as possible Rears are great at (a) but less effective at (b) than toggles are. Therefore using a good breeze to achieve (b) a soft stand-up landing on rears is certainly possible.

...because UPT gives recommendations (at least I take them as such). E.g. they recommend standard fitting main canopies which does not mean that a size smaller or bigger does not fit. It might just not be too convenient to pack (in reasonable limits, of course). Overstuffed rigs have been linked to delayed reserve deployments. Is that a risk you want to take?

Let it go.

Rears do not put energy into the system (unless perhaps you are talking about potential energy due to planing out), whereas fronts increase kinetic energy. Yet again, I have to say stop fucking jumping until you have the very basics of canopy flight explained to you by someone who knows what they are talking about. In fact, I suggest you sit through an AFF ground school. And listen. If you turn out to be a troll, I will hunt you down and blow up your bridge!

I know of at least two people who have smashed femurs from a toggle coming off the steering line, and I am not that well connected in skydiving. I am not saying that rears would have saved either one from the titanium club, but I do know that toggles have come off resulting in injury. ETA: landing on rears is also in BillVon's downsizing checklist, and lots of people recommend exploring all aspects of a canopy's envelope before downsizing - I think this is a relevant skill to learn (with proper instruction).

[My bolding] Dude - you need in person instruction before your next jump. I tried to be helpful but this question (minus a question mark) is serious cause for concern. Don't jump again until you have addressed it with at least an instructor and preferably a canopy coach. Please. ETA: I really can't decide if you're trolling. Shame on me if you are.

People never rise to the occasion. They fall to the level of their training. That is why we have people making stupid low turn mistakes when confronted with a problem like a near canopy collision on final. Agreed, Dave. Just trying to help out one flat turn at a time! I wonder who trained Shah to use rears in the pattern? I once saw someone who had got into the habit of using all rears have to unstow her brakes at flare height to use them!! (because she had been told "nobody who knows how to fly a canopy uses their toggles")

Why are you using rears at this point in your pattern? A better option would be to do your flat turns using toggles. This should be your default "save your arse" flat turn (with the exception of just post deployment) and the more you practice it the more likely you will, actually, be able to save your arse.

http://flight-1.com/sport/certification/

As with most canopy skills, the way to start is up high. Get a feel for how far you need to pull down/out on the rears to get the canopy to plane out. Also, get lots of practice on where the stall point is on the rears. This is the big danger in landing on rears as the stall will happen at a higher speed than a toggle stall. In general, the rears are going to flatten out the glide of the canopy without slowing it down as much, so it is a good idea to do your first rear riser landings into a good headwind (12-15mph) and be prepared to either PLF or slide out the landing. Finally, ALWAYS keep your toggles in your hands and don't be afraid to bail on the rears and finish the flare with the toggles if you don't feel comfortable (it's ok to just drop the rears and go to toggles). Yes, it's safe - if you don't fuck it up! And I believe it's a good skill to practice. It's one of my essential skills to master on a new canopy.

Of course he was out of control!!! If someone was in control and trying to deploy a reserve, why would they be on their back?

In my opinion you are way off beam here. The DZO has done everything right and should be congratulated for following a logical investigation, using the data collected to make the safest decision and then communicating his decision so eloquently. This is a template for how things should be done.

Exactly! In our case (semi-stowless bags), "line dump" is a meaningless term. The issue is caused by the canopy coming out of the bag prematurely - not the lines coming loose. Premature stripping of the bag off the canopy can lead to the slider moving down the lines before it is forced to by the inflation of the canopy and/or bottom skin inflation instead of span-wise inflation through crossports. These can both lead to slammers.

Really? So your post was an attempt at humour?

No. See below. The problem is that we don't have a consistently applied definition of "line dump" in the skydiving community. Thus many say that line dump DOES NOT lead to hard openings -- because "line dump" refers only to the lines other than those in the locking stows dumping out. If the locking stows go or the canopy in any way starts coming out of the bag prematurely, that's a separate category, "bag strip". Others say line dump DOES lead to hard openings, because if the lines in one or more of the locking stows dumps out prematurely, the canopy can start inflating prematurely. Lines are lines, and anything they prematurely dump out of, including locking stows, therefore counts as "line dump". Thus much of the battle is about the definition of "line dump", not what the cause of hard openings is. That's exactly what I was getting at. My bad for being too vague on defining the terminology. The key point is that the canopy stays in the bag until linestretch. I jump a semi-stowless bag (just two locking stows) and have not been slammed yet.

There are problems associated with a removable slider that do not occur with a normal slider, including: - dropping it when you remove it. - not putting it back on properly causing a hard opening - time taken to reattach it - the fact that most canopies do not come with it as an option so you are essentially a test jumper This list is not exhaustive, but should indicate that everyone should NOT jump a RS. You need to think a little more (or just know a little more) before throwing out advice for everyone.

Flight-1 basic courses (101) are open to anyone cleared to self-supervise. Hop n Pops can be quite daunting until you actually do one. Lots of people find them a huge rush and really enjoy it after the initial fear. Remember you have more time getting out at 5,000' than you do when passing through 5,000' at terminal velocity.