pchapman

A few notes on Aerodyne's reply: -- They partially fault "initiating reserve deployment in an unconventional manor" (sic). But it isn't clear whether the reserve was popped by pulling on the cable under the pin cover flap or not; they need to talk to the folks in Sweden more. The first frame of the video they received does show the rig on the ground and the pin in a person's hand, but it isn't clear what happened before that. Was the pin pulled manually with the rigger's hand perhaps against the top flap as Aerodyne suggests, or was the pin pulled the normal way, the pilot chute didn't launch, and then they put the rig on the floor and got out the camera? -- They show the "excessively long" loop to be 7/8" above Aerodyne's specs. (But see my next point too! - it isn't that much.) But how much actual slack was there? That is, before pulling the pin, how much could a rigger compress the pilot chute and pull up excess loop? Plenty of rigs have loops that are above some manufacturer's spec, some of which are more realistic than others. The loop sounds longish but I wonder if that amount should be considered dangerous for an ideal rig. -- Aerodyne claimed: "Typically, we would use a 115mm (4 ½”) with this combination." This specification is below any in the manual whether for a smaller, medium, or large size reserve. And the specs are shown only for Smart reserves. Looking in my Icon manual dated August 2011 (which is still current), it shows loop lengths of 12.0 to 14.0 cm for the Smart 150 to 175 reserve, in an Icon I5. Although the rig is an I5, we haven't been told what reserve was in use. If it isn't a Smart reserve, then there is no exact directive as to what the proper loop length will be. (The loop in the incident was 13.7 cm, within the range suggested for the rig, depending on reserve size.) So while the loop length may have been long in that it allowed for slack when packed, Aerodyne has done a very poor job in showing what length it should be according to the manual. -- For the first time, we see that this was a case of popping the reserve with the main in place. The first photo in the pdf is a good example of how the main can interfere: The main side flaps just slightly overlap the stiff reserve bottom flap, making it harder to lift up. That flap in turn adds resistance to the reserve side flaps, which in turn resist the pilot chute. At least Aerodyne attended to the matter quickly and tried a variety of tests, and had the pilot chute always fire. Although they got limited info from Sweden, both of their claims as to the cause of the problem are a bit weak. To summarize: a) it isn't clear if the reserve was activated the unconventional way they said b) it isn't clear how much slack there was in the loop, and their own claims on what the loop length should be do not match their own manual Google translate of the Swedish portion is below. Pretty mangled though. Is it saying the grounding is lifted or not?

That's from the CSPA for CSPA DZ's, not a government rule. No mention is made of meds either way. For an affliction such as epilepsy, a yearly signoff by a doctor is also required.

An IAD or S/L FJC would be pretty useless; but an AFF course would be a little more useful. Still, the information presented might all be a little over simplified at the AFF #1 stage. It seems to me that it would be more useful to pay an instructor for an extended DZ orientation, & emergency procedures review, etc, before a coach jump demonstrating skills from briefing to landing.

What design changes did Aerodyne make then? I know they've tweaked the design in some ways (occasional bulletins attest to that) but don't know all the details. EDIT: I've since heard that there were some changes to the reserve pin cover flap, possibly the length and/or stiffness, for at least some versions. Details unconfirmed.

IF you really do want to do accuracy jumping, and will be at a DZ where that is done, then the PD Zero makes sense. Pea gravel bowls are getting rarer, but maybe if you are thinking about accuracy you've got a DZ with a bowl or tuffet already lined up. It's a lot less fun to do any skydiving discipline if nobody else at the DZ is playing the same games! If you have the money, sure, get two canopies, maybe a new Zero and a used something-else ZP that is known for soft openings. Better look up the difference in pack volumes though. Traditionally, accuracy canopies were huge even for their square footage, but more modern construction on the Zero might bring that down. Otherwise a 265 and a 210 might be a little far apart in pack volume. If you did change canopies back and forth, you may need to buy a rig that uses a long closing loop (that can adjust more) that goes from the tray or reserve wall, not one with a short loop from the bottom flap that is not supposed to change size much at all. I jumped a 265 canopy at 140 lbs plus gear for something like my first 500 jumps in all wind conditions (in the 1990s), only standing down when others started to do so. It wasn't quite as slow as a Foil but still slow (Pioneer Titan). So one can fly big stuff in strong winds, if one has accuracy skills. Usually one isn't actually backing up on landing, even if doing so until 100 feet. However, one thing that has changed is that one might be jumping turbine aircraft instead of a C-182, so you don't always get to pick your own spot as easily. That's where having a faster canopy nowadays makes it easier to get back to the LZ.

At least someone managed to try to summarize things from this messy thread! Sounds good. You wouldn't do the end of final approach in 1/4 brakes in non-emergency situations. You'd make sure to go to full speed in time for the canopy to regain speed, and get into a steady glide after the little dive it might do if one let the brakes up quickly. So that makes it OK to be in 1/4 brakes, if you like to "slow the world down" and to make glide path control easier. You'll still want full speed for the actual landing. That should allay your concern. (I should note that there are some complications to using 1/4 brakes for glide path control. On a modern canopy going from zero to quarter brakes may extend your glide, or shorten it, depending on the canopy & winds.) Yes it helps with landing where you want for a number of reasons, not just for staying over nicer terrain. When you turn final, to some degree you are committed. (Also depending on traffic around you.) In an extreme example, if you turn final at 200' up and 200' out, expecting a 45 degree descent to landing, and misjudged the wind and are coming straight down, you'll miss by 200' short. If you made the same misjudgement and turned on final at 800', you'll miss by 800' short. I find that a landing pattern can be as low as you are comfortable with, as needed to get around the corners in sufficient time to do what you want to do, with enough margin of error. (Again, modified as necessary if you need to fit in with traffic around you.) So if you are on a new canopy and want a nice long 30 second final approach, keep your pattern high enough to do that. If you (down the road) are comfortable with a carving 180, with a margin for error, rolling out wings level a few seconds before starting to flare, then whatever height you need for that is high enough. That's all my personal opinion only; I don't know what others teach. This isn't to encourage low turns, just that there isn't anything inherently wrong with picking different pattern altitudes. The only (?) real downside of a lower pattern is that you don't want to be crowded in time and altitude to get turned back safely into wind and have the canopy flying the way you want it before the flare. One also uses the length of the downwind and the base to adjust for the winds and desired landing point. So if necessary the base leg can disappear entirely if one is getting too far downwind. That's an example of where the angles and position over the ground matter more than altitudes (other than the all important 0 altitude point where you meet the planet). Also stand out in the landing area and watch others' landing patterns, and get an idea of what works and what looks sketchier. If you can, take along an jumper who has some experience coaching canopy flight for a second opinion.

A couple odds and ends comments: -- While classic accuracy folks generally do things by eye and don't need, say, audio alerts while in their little pattern, I have seen one competitor pace out each new contest site to get a better feel for the dimensions. -- If one is learning to do a normal straight in landing, then what pro swoopers do with altitude alarms is largely irrelevant, whether or not one thinks they are godlike. They are doing a dynamic turning maneuver from their setup point to landing. For a 'normal' landing, the final approach is more of a straight line. So it doesn't matter if you've turned in on final at 250 ft or 400 ft -- that has little effect on your straight in approach and ability to hit your target. What matters is the angle you pick. -- Being able to judge angles, estimate angles of flight in different wind conditions, and judge the winds from one's drift or wind checks, is more important than hitting exact altitudes. "Angles are more important than altitudes." Still, having altitudes as targets can be useful for newbies to get an idea of what a typical circuit can be like, and to reduce the uncertainty they can have about the invisible 3-D paths that can be followed.

There are some quite different philosophies here on how to gauge your circuit. Part of the issue I think is that if you are experienced, you can have contempt for anyone who insists on gadgetry and exact altitudes and descent rates, since that crap isn't needed at all to land safely and accurately. On the other hand, using some exact numbers can be helpful to newbies as a starting point to work with, an initial reference for a reasonable pattern. There are no perfect, ideal numbers, but they are a starting point for learning to fly an accurate pattern that somewhat fits in what other skydivers do. The teaching style may differ depending on the newbie's technology, complicating things. You can teach a little differently to someone with an analog alti like in the old days, vs. someone with a digital alti and audible altitude alerts under canopy. Newbies still have to know that the numbers can be thrown out the window for safety, e.g., don't wait until you see 600' to turn base if that's going to put you in the trees due to the wind change. And that if you are in a busy traffic pattern, you try to go more with the group, not the numbers. Just my opinion, but I think it is OK to teach some precise numbers. It is a crutch, and not necessary in the long run, but still useful to someone new.

Hey Nova, FB is convenient for uploading batches of files, but has the issue that the viewer must have an account and be logged in. That's still needed even when someone leaves their uploaded photos on the default (?) setting of "Public". No friending necessary, but logging in is required. If that's a problem for anyone who really wants more photos, bug me and I'll get them to you somehow. More trivia about the canopy: -- The MA-1 was a little newer, 1958, built by "Jayval of New Mexico". -- Today I pull tested the Navy Conical, having only thumb tested it prior to jumping it. Two spots were OK at 35 lbs. Another spot I tested to destruction, and it tore at 41 lbs on a pretty accurate scale. That's actually pretty impressive given that the old Type I fabric* is only rated to 42 lbs minimum strength when new. I acknowledge that nylon will chemically slowly degrade over time, but this is one data point showing old does not necessarily = weak. -- From looking at prior damage to the canopy, it had led an eventful life: Some patches on the canopy retained the original material inside, where one could see the damage wasn't poke holes from landing in a tree, but sometimes had scroring leading up the the 1-2" holes, and/or fuzed thread ends at the tears. In other words, I think the canopy had gotten a bunch of friction burn holes at one time. Plus one line had been replaced, being normal white instead of the yellow that everything else had earlier been dyed. So at some point a jumper had an exciting ride, perhaps on a high speed opening, burning a bunch of holes in their undiapered round reserve! * according to Poynter's, MIL-C-7020 Type I was used in the Navy 26', Army C-9 etc, and has 80-120 cu ft/min permeability, so it was effectively high-po before LoPo came about. While PIA TS-108 says to test to 40 lbs, that's pretty tough on a fabric only rated to 42 lbs, when the later George C. Harris F-111, the real stuff, was rated at 45. So I think 35 lbs is a reasonable test for older materials.

Exit weight I should have mentioned: about 185-190 lb with all the gear. I'm glad I'm still reasonably skinny. Edit to mention more about container design: No kicker plate was used, although the pack job was tight. No bungees on the belly container. So those are additional reasons for the weak pilot chute to launch even worse. (The belly container is a modification of the main container that was hacked off the 1980's rig that furnished the 'cutaway harness'. It has been mainly used for ram airs as cutaway canopies, and not specifically for rounds. Instead of a kicker plate these days, the way to do things would be a kicker flap, like in modern sport reserve containers or I think the T-10 MIRPS belly mount.)

Yesterday I jumped a 55 year old canopy, a 1957 26’ reserve, a Navy Conical I think. Bill Cole and I think it probably was once one of his, that he dyed yellow as an attempt way back when to see if the dye would reduce porosity and descent rate. (I can't rule out that it could have been used as an airshow cutaway canopy later on too.) It has seen some service, with a replaced line and a bunch of patches. Descent rate was about 20 fps down low, based on video timing vs. alti checks. Yes I was a little apprehensive! (When I did an alti vs. watch time check up high, I had blown through 1200' in well under a minute. Even without doing the exact math, I knew that didn't sound like much fun.) The canopy was worn as a 3rd canopy on my belly, on a second harness. That way I could both watch the deployment and have no worries about chopping it if I didn’t like how it flew. But it did mean extra weight and a lump on one’s back when trying to land a round. When a pilot chute has as weak a spring as an ancient MA-1, then it isn’t bad to have the canopy in sight while it deploys! The opening, after a 3 second delay from a C-182, was quick enough on video but at the time it seemed rather slow: I pulled the ripcord, nothing happened, I assisted in pulling open the flaps, the MA-1 bounced in the burble and bounced off my face, and “finally” – about two seconds later – started to pull the canopy away. No wonder jumpers had to protect their Capewells when cutting away with a belly reserve in the old days. The canopy sure flopped around in my burble as the MA-1 extracted it. One thing that was worse than even the old days was that elastics were on bights of line but not attached to the belly container's tray, reducing the little bit of staging that provides. Canopy inflation was good, pretty symmetrical, with just a little extra dishing on one side (when looking at video frames). It's an undiapered round of course but with the low speed the opening wasn't hard. “Rebound:” There was some good wake recontact after initial full inflation. It happened so fast I didn’t notice at the time but it’s clear on video. About a third of the canopy deflates and one line group goes all slack before second full inflation. Canopy performance was poor, with seemingly very poor forward speed, despite having been "modded". There were 3 traditional vents at the back, which later had been meshed in too. I thought the mods would give good stability, but occasionally the canopy would randomly rock forward and back in an oscillation -- which suggests it wasn't consistently spilling air out the back and flying forward. Or perhaps even the slightest touch on the risers, to start a turn, might disrupt its normal flying and cause it to rock some seconds later. Not sure exactly what was causing the issue. Turns with rear risers were slow but worked. The oscillation was not nearly as bad as what one sees in old videos of flat circulars, and only occasional. But it unexpectedly rocked back a few seconds before impact, so I ended up getting dumped on my back on landing instead of getting in the proper PLF I wanted in the low wind conditions. The impact wasn’t that bad but there was a little whiplash. For those on facebook, a bunch of pics are at http://www.facebook.com/media/set/?set=a.10152323186345657.941373.855495656&type=3 For just a quick look, I’ve uploaded a few pics here. I don't feel any burning desire to jump the canopy again; I think it'll be donated for a kid's room decoration next.

A couple guys at a local DZ have done a blindfolded jump, on student gear, with a radio to talk them down. The scary thing isn't the jump itself, it's your friends on radio, depending on how much they want to screw with you. After they give you flare commands while high up in the air, you're gonna want to disbelieve them, but at some point, the ground really will be there. On the jump I saw where Jeff King was the jumper, the final flare command was OK but a bit high (better than a bit low), Jeff flared too hard and popped up a bit, started feeling for the ground, running a little with his legs, started to doubt himself about whether the ground was there, let up somewhat on the brakes, and dove and pounded in. No worse than a typical bad student landing though. A gutsy jump!

There was a good sized thread or two on this in the past - look for them for some ideas.

For another partially irrelevant but interesting test, attached are photos from my test from last year where four untensioned CYPRES loops were inserted into the cutter -- as many as I could cram through the hole. The result was 3 cut loops, and one that still had roughly one or two of its 'bundles' of thread (out of 12 I think) that wasn't cut. Putting tension on both ends, it is clear that those strands have not been cut. Pretty good I figure, getting through most of 4* 450lbs = 1800 lbs of Spectra. I have video; don't know if I'll bother to post. The 'tops' of the loops were pointing up slightly when tested (as in photo 1). The three tops of the loops that got cut, they shot right off the table -- the cutter spat them out with a lot of force. (I annotated the photo of the closeup just so it isn't as easy for the photo to get out there without being taken in context -- it isn't a "cutter failure"!)

Ok, I don't know about the movie or the details of how far nose down the elevator was stuck, but one can come up with scenarios where it would fly upside down. The elevator would normally be in a position to trim the aircraft to 1g level flight. ("trim" i.e. - everything balanced in equilibrium) Shove the stick forward, and there'll be a point where the elevator trims for 0g flight. Shove it forward more, and it'll be in trim for -1g flight, so if you rolled it inverted, it might fly level inverted. That's without taking the wing design into consideration. On an aerobatic aircraft, the above might work well. In an aircraft designed for upright flight, the wing will be less efficient upside down, so more down elevator might be needed. So really far forward stick might just trim the aircraft for inverted flight. An added complication is speed stability where the faster you go, the more forward elevator you need to trim, and the slower, the more back elevator (when upright). So in level flight, shoving the stick 3" forward won't necessarily make the plane dive past the vertical. Everything might balance out again at a high speed that the plane can take, or it might accelerate until the plane breaks apart. Depends on the details. Overall that complicates things but could help, for if the aircraft has enough speed stability, if it pitches up a little and slows or dives a little and speeds up, it will tend to return to the original speed and flight path, even with a stuck elevator. It also means that the movie aircraft would trim at some speed inverted, even if not at the original speed. Adjust engine power to find a speed where the aircraft does trim level inverted. (I'm not sure about fuel feed and long term oil feed for typical jet engines inverted though -- CarpeDiem said that in the movie the engines did fail at some point) All in all it sound slike some aspects of the movie scenario COULD work, but getting it all to work together in real life could be tricky, especially for an airliner. There was a famous aerobatic pilot in the UK back in about '70 who had one wing start to fold because the lower joint failed, wasn't wearing a parachute, rolled it inverted, the wing stayed jammed in place (since the broken joint was now in compression not tension). For landing he rolled it from inverted to level at the last moment, putting a furrow through the grass with the wingtip, and skidding it in on its belly before the wing could fold up. That's the only "save it by flying upside down" story I can think of in real life. Small planes have been landed using trim when the elevator disconnected or jammed, but it isn't necessarily easy. The UK case is an example of where the roll back from inverted needs to be done just before touchdown. Whether you can do that with an airliner, its speeds and roll rate, I dunno. If one could even achieve a Sioux City (United 232) type crash, killing a third of those on board, and do no worse than that, that would be a good outcome. (P.S. "AA 261" is Alaskan Airlines in this context, not American)

Now that's an unusual observation. Why would that be? The proper thing for the thinking skydiver to do is to turn or flare turn more into the wind. But the way I can see your idea coming into play is that if one is crosswind and the ground is moving sideways under you, would some people tend to instinctively try to "straighten out" to align their body with the direction of ground motion and remove the unnatural "skidding sideways" movement, by turning more downwind? Sort of a 'steering into the skid' idea that might make sense when driving but is bad when landing crosswind?? On the video that Alexa posted, if the jumper with the camera was landing upwind, then it looks like Alexa might have been pretty much crosswind, but turned almost straight downwind in the last seconds. That landing looked hard! Alexa: Hard to tell in the video at a distance, but if you had the altitude to make it some distance into the field, and also turn downwind from crosswind, then you also had the altitude to turn at least mostly upwind. Unless one had extreme turbulence, it might bounce you a little left or right randomly, but there's no reason you couldn't generally overcome its effect with moderate toggle input. I guess a partial answer to how much to turn is that over time one will can practice how much one can turn one's canopy before letting it recover and flaring. In other words, how long a final approach one needs after a certain speed turn. That's part of learning "how low is too low" for a turn. In addition to doing a simple turn to get a little more into the wind, the options one can do are (a) a braked turn which is good for not diving at the ground but takes away energy you'd like to have for a good flare, or (b) a flare turn where you turn during the flare itself, trying to point a little more into the wind so the crosswind isn't sliding you sideways (which is rather hard to deal with to run out a landing - so a PLF may be necessary). I can't give a simple answer because it all depends on getting to know your own canopy. As AggieDave said, practice and get video. Landing upwind is better than landing crosswind, but landing crosswind is better than landing in a diving turn that you couldn't get out of in time.

MotoGP? That's the thing with that Rossi guy? Dedicated tracks only for the championship series makes sense for safety... but it is more fun to look up TT race videos on youtube (or just watch bits of TT3D again).

Too expensive (compared to regular gear) and too limited in its use (compared to, say, a 2 seat airplane) for people to buy "to take their friends" skydiving. If someone buys (and maintains) a whole rig for themselves, it is normally a business decision. The few guys I know who have their own rig either are full time skydivers who move around with the seasons, or got into the tandem business early, before every DZ had a pile of them (and so were a sort of specialist professional).

Nice. I like it when he hits a straight stretch, and opens it out to a consistent 200 km/h on the single lane dirt track... (Sometimes the computer generated speedo display is overreading from wheel spin so momentary speed jumps aren't reliable.) Spectators next to the track give it a good 1950's feel though; everyone shares the risk.

What's Petraeus' problem? Doesn't like girls over 40? Her birthday party must have been a downer. She just turned 40 yesterday the 9th, lost her lover, and is under FBI investigation. edit: Oh, she's married too. More awkward.

Brian has a lot of knowledge and spends the time to make videos and write articles. But then after putting so much effort into trying to educate people, much of the time when he posts a link to a video of his, he gives no description of the contents or conclusion of the video, nor even gives a hint of what the heck the video is about. So without any description it unfortunately comes across as a little arrogant. It seems like a case of, "All hail! The great God Brian has spoken. To youtube we must journey to receive his words of wisdom. There shall be no questioning or deviation, for all his words are Sacred. The video is 'worth watching', for one and for all!" Of course one can take it or leave it, nobody is forcing anyone to do anything. Still, why go through the effort of trying to teach something and then being so unhelpful? The same applies to other people. If some newbie comes on this site or some acquaintance emails me, "hey dude check out this cool youtube video", I'd be equally tough and tell them to put a little freaking effort -- and a little courtesy -- into providing a description.

Canopy? Not sure. Small flares on it, suggesting not a classic accuracy canopy, but more like something from Flight Concepts [edit: your edit beat me to it...]

Front outside line used in order to spiral. Less pressure than trying to hold down the front riser for a long time. Guess he likes a bit more speed than doing toggle spirals on a bigger, slower canopy. Is that trick used much??

In that or a similar picture, published in a magazine, one could just barely make out that his special Cypres displayed "08 12" (I think) after landing, not the usual "0" . Not sure what that was about...

One shot operation got mentioned in this post onwards: http://www.dropzone.com/cgi-bin/forum/gforum.cgi?post=4369765#4369765 (Differing opinions on whether it was 'just pull them down hard' or 'pull open, then give them a knock downwards') The 'safety precautions got less' in order to make it easier to activate in the air, something the original design wasn't intended for. Here are some pics of a 1 1/2 shot being opened. (Sorry, pretty crappy fuzzy webcam captures, was set up too close and on low res mode.) Edit: see also Andrew Hilton's photos of old releases http://www.flickr.com/photos/vintageparachutegear/sets/72157622676844920/