pchapman

I'm glad I took a few hours to download a bunch of posts from recent years that I hadn't gotten around to, some of the story threads & incident discussions & technical discussions, etc. (Just downloaded manually, no scripts, so one had to click 'view all' to get the full thread on one page for long threads, and any attachments one really cared about, had to be downloaded manually.) It's one of those things where to the inexperienced, one thinks, "should be easy to write a few scripts to save all that stuff", but as Admin says above, they didn't find it that easy to migrate the old dropzone.com format. (And they still lost attachments in that move...) Hope they find a way to bring back some of the old info, even if the site wasn't as popular in recent years as it once was.

This is nitpicking, but is the "foreign jumper" defined more closely somewhere? I assume it would be about RESIDENCY not CITIZENSHIP. Residency would make more sense? (Not that making sense is a criteria for the FAA...) So then a US citizen living and working in Europe could bring their non TSO'd gear to a US boogie without being told they can't jump it. Similarly, I'd expect one can't have an H-1B visa or Green card holder living and working in the US for decades, be able to jump any gear they want, because there's no US TSO requirement in the country of their citizenship.

The 2008 Aerodyne bulletin stated that the French parachuting federation made it mandatory for AAD cutters on rigs to be above the pilot chute. But I don't actually know the current situation in France -- what might have changed since then, what exceptions there might be, etc. So I am interested in hearing more about this whole situation and what the opinions are in France... (Edit: Also interesting is that this new bulletin is from the civil aviation authorities, rather than the parachuting federation. Like something from the FAA rather than the USPA.)

I'm confused by the documents out there. The new French document (F-2021-003) says that jumps with a cutter below the reserve pilot chute (the 'extractor' to literally translate the French) is not permitted. And that's what Arnaud above says. But, the title block in that document says that the bulletin applies to Aerodyne Icons, and that it is only Aerodyne they are talking to. So is the cutter position thing for all rigs or just all Icons? But if it is all rigs, does that also temporarily ground Racers & Teardrops & Javelins & Wings etc? But if it is just for Icons .... I thought Icons in France already had a mandatory change of cutter location from the kicker flap to the side flap, above the pilot chute. That was noted in the 2008 SB210108 from Aerodyne, which made it optional in general but said it had been made Mandatory in France by the French authorities. (And I guess all subsequent Icons have had the cutter built into a side flap. ) So in this case, has anything changed at all? Here's a Google translate of part of the new French document, with a few mods of mine for the worst bits of translation: This doesn't really clarify if it was regular manual pulls on the ground that were failing, and then the tests were done on manual and/or cutter activation, or what exactly was tested. (Similar to what Skydiverek was wondering.)

Fair enough. Although if someone went to the reverse S-fold because they have difficulty packing , if they pack the normal way -- everything in a double S-folded stack before bagging -- they might well tend to lose control and and have the bottom of the canopy "squirt" out of the whole stack, again messing up the slider placement. But I'm sure we'll agree that either way, one has to control the slider at the bottom of the canopy. (I've got a couple thousand jumps on sub-100 crossbraced canopies and I prefer the reverse S-fold. Still easier than trying to control the full stack, especially on a canopy that is short from bottom to top.) But back to Pilots, which like almost any ZP canopy, seem to be able to slam people in rare instances...

Got mine, maybe a week ago, and I'm even across a border in Canada.

I thought it was a pretty common concept that smaller canopies tend to be more sensitive to given inputs. This all goes way back, for example being part of Brian Germain's wing loading chart and all sorts of stuff he has written. Accompanying his chart: But: I also recall that he (and others like me) say not to take things too far -- All that isn't supposed to be an excuse for a big guy to start loading up his canopy excessively 'because it's more docile for me'. So one is still free to agree or disagree with the exact numbers in that quote at the start of this post, about a 1.2 loading for the poster being like 1.0 for a smaller person.

Odd company. Basically there is 60+ years of a few guys fiddling around with aircraft recovery parachute system designs on and off, and getting a few patents, but no product produced or marketed. Their 'thing' was a 3-unit aircraft recovery chute that blows the wings off and has each wing and the fuselage descend under a separate parachute. (Umm..... that's different.) Then in 2018 they hire an ex CEO from BRS, well known for their recovery parachutes. A year later: [Emphasis mine] Then recently they started to get a few awards or development contracts: So somehow they have gotten a real team together and found a little funding. They seem to have a line of recovery parachutes for ultralights etc but I'm not sure if they are really out there in the market yet?? The 'big idea' they seem to have now is to design recovery parachutes for all the eVTOL / Urban Air Mobility vehicles that are being designed in the dozens these days. Will be interesting to see how the company deals with Strong: "Great, we acquired a whole lot of parachute system production knowledge, and they actually have the experience of selling bunch of stuff to a variety of clients!", but also, "So, what's with this sport parachuting and tandem stuff -- you know, where people tried to sue the original company to oblivion even if some accident had nothing to do with the product other than that some idiot used it -- How does this fit in with our future plans at all??" But I don't know much about ASR or the recent ups and downs of Strong... so if someone has more accurate knowledge, let us know...

Yes, fixed, thank you.

Generally emergency procedures may assume that you've already made "one try" to fix the issue, and that means one short try. Can't get PC out of pouch? Try once more, but then go to emergency procedures. I would tend to stick with that "one try" idea for an entanglement. With the usual warnings about how people can stretch "one try" out way too long. However, I haven't actually spotted anything on bridle entanglements in the USPA SIM (but I'm not really familiar with it), only more generic "out of sequence" deployments, which it kind of ends up being if the bag is out but PC bridle wrapped around a foot. The SIM basically says for premature container opening to " First, attempt to deploy the main pilot chute for no more than two tries or two seconds, whichever comes first", then cutaway and use reserve. (5-1 Skydiving Emergencies) Huh, "two tries" in there! Well, yeah that works with the qualifying statements but I suspect most instructors would just say "one good try" or similar. For pilot chutes in tow, the SIM does allow 'the two methods' -- cutting away or not cutting away first. And for "partial malfunctions" in general, for all the many many varieties of 'container open but no good chute', the instructions are just to cut away and go to reserve. So, are there specific recommendations about a bridle entanglement somewhere? (Not just from the USPA) They do exist for things like tandems, but in that case the entanglement with the drogue bridle normally happens shortly after exit at altitude, so one can afford to try to fix it for 10 seconds like the UPT Sigma tandem manual says! Skydiving organizations do expect a jumper to try to fix some entanglements -- like with a camera helmet -- Otherwise, why would any organization bother with all the recommendations to have a cutaway system for the helmet! The Aussie APF's great malfunction video series, for horseshoes, just says to cutaway and deploy the reserve -- with the video of the the test jumper doing that, but with little tension on the main risers [Edit: fixed from 'reserve risers'], the reserve fires into the mess -- but clears it. (Even with a tersh, there's a fun jump...) I only skimmed the video but didn't see a specific Entanglement mal. One thing I wonder about entanglements is what to do with the RSL -- as that will fire the reserve as one cuts away before pulling the reserve handle, if the main risers are tensioned and clear the rig. Does anyone address that? Does having a second of time between cutaway and firing the reserve improve the outcomes in case of an entanglement? The Sigma tandem manual these days has stuff on releasing the RSL first before cutting away, when dealing with various messes behind one's back -- but again, their emergency procedures tend to happen at a higher altitude. The USPA SIM does have a section (5-3) where it lists all the ways that an RSL can complicate procedures in the event of an emergency..... but does it actually go through those messy scenarios and what to do about them anywhere?? With a high speed entanglement in regular skydiving, time is very short, and those RSL tabs may not be easy to find in freefall quickly. I figure theoretically it would be better to release the RSL first but in practical terms it is hard to do in a short "one try" time period...

Never was a member.... but when visiting Germany in the summer of 1992, I stopped by at the Lahr DZ one weekend. Put in a few jumps in until the airplane transponder went on the fritz and they couldn't climb high. The fellow in charge maybe took pity on a student roaming the country who had walked to the air base from the local train station, so he didn't charge me any club fees, and gave me free rig rental. Slept on a barracks couch. I think fuel was at military prices, not high European civilian prices, so DZ jumps were cheap compared to pricy jumps at civilian DZ's in Europe. So I got a sweet deal. After a hop and pop to demonstrate I wasn't a total idiot, I did a couple two ways, breaking off at 3000'. ("I mean, it's only a 2 way, why break off up at 3500'?") Looks like Volker Kock signed my log book, though I didn't jump with him. Peter Landry (at least once a Canadian Nationals meet director) also showed up. Rental / student gear was EZ Flyers with Mantas or the super sluggish Laser 288's. They had new Telesis rigs but they were temporarily grounded after some student a few weeks earlier had had a main riser catch under the reserve tray during a mal, leading to him spiralling in and being paralyzed. While I was there someone else renting failed to catch an FXC set to 2000' and came down under the main but trailing the round reserve, the diaper having held it shut. It was the best defended DZ I had ever seen: DZ ops were housed in a large hardened aircraft shelter, complete with siren and rotating beacon as the heavy blast doors opened. Very impressive... but then there's a little C-182 inside! They called it the Yellow Banana I believe. By 1992 after the end of the cold war, at CFB Lahr the F-104 Starfighters were long gone, the Kiowa helicopters were gone, and many personnel were off doing peacekeeping things in Yugoslavia, so it was a quiet place, only a couple years before the Canadian military bases in Germany shut down. I did take some perhaps illegal photos on base, as attached. I had also been to Germany a bunch of times as a kid -- Great fun in the cold war, with so much military hardware to see on the streets and in the skies. Note the "Panzer crossing" sign outside the main gate. That's all for my most minor of exposures to the Canadian military's German sport parachuting club! Cheers Rob.

A lot of people are more likely to follow what they are told when they understand the reasons behind what they are told. There are plenty of dumb, incorrect, and arbitrary things that people are told in life, so backing an instruction up with some reasoning can be helpful.

Although I haven't been in the aerospace industry a long time, I would think that aero engineering isn't the only way to get into the aerospace businees. Not everyone at the companies are doing computational fluid dynamics of air flows or calculating shear stresses in carbon fiber D-cell spars. There's plenty of mechanical & electrical engineering and software coding to be done. So there's a range of engineering fields to study which can be useful both in aerospace and elsewhere.

It was NOT a taildragger, just a plane with a bigger / longer cowl & radial engine. Looked like a Nanchang CJ-6, something like that. The riding mower and the plane off to the side of the runway could be seen in a new news video. Not that any of this really changes the issues as mentioned in the first post. ( https://montreal.ctvnews.ca/video?clipId=2235845 )

Thanks. I had only seen less complete English language news outside of 'la belle province'. On the video, the way Mario explains the lack of vision just at landing, suggests the plane was a taildragger, which makes the visibility issue a little tougher. Lessons indeed about communication at smaller & private strips where it isn't like ground service vehicles and planes are in contact with ATC.

I almost confuse Donald Rumsfeld with Robert McNamara, every time I think of them. Seemed like top-down efficiency experts, who worked both in private industry and government. Both with documentary videos done later in life (by Errol Morris). Although as someone noted elsewhere, McNamara apparently did have doubts about his past, while Rumsfeld never conceded much.

So are there no other requirements other than minimum distances to obstacles, for an LZ size? Eg, USPA (at least in my older 2018 SIM) shows 330 ft to an obstacle for a solo student. So can one open a DZ with an LZ that is a 661 ft circle? Is that sufficient or is there some other rule that would make the USPA say "Nope, you need to have a decent sized landing area, PLUS the 330 ft in all directions." (Mind you, as a novice at USPA rules, I can get into other weird musings about the BSR rules: Trees covering less than 32,292 sq ft are NOT an obstacle? A concrete runway is not listed as an obstacle? So you can put a student LZ ontop of a 100' * 100' forest surrounded by runways & taxiways? Either I'm missing something or the BSRs in this case are way too lax compared what any actual DZO would do.)

The website seems to work for me. Even jumpshack.com redirects to them. Aha.... "plabsinc.com" works. "www.plabsinc.com" fails. Despite the latter being the link on their facebook page. Although even for the version that works, the intro page is blank except for a "Skip" link to the real page -- Maybe the first page had some deprecated Flash animation or something that is so, I dunno, 2005?

Anyone can become a dropzone bum. It takes more work to get a decent job / career. Which can then pay for lots of skydiving. (Like TampaPete said.) Everyone likes the "right" to do whatever they choose in life. But young adults often can use a boost / support from parents to get an advantage, and that financial power does give them some leeway to impose conditions. One can argue about those conditions, but one can't always avoid them...

Yes I meant "the whole point" in the context of skydivers using tunnels, as one of the reasons skydivers want to use tunnels. Rather than the obvious "The whole point of tunnels, which are commercial enterprises, is to make money for their owners". Even in skydiving I have seen waivers where one has to state that one is "fully recovered" from any injury. Bad ankle, dodgy shoulder? Doesn't matter, you can't do the first jump course unless you claim to be perfectly healthy, as the DZ doesn't want to play the role of giving expert medical opinion. I think we agree on the liability thing.

It would seem silly to exclude people just because of prior injury. The whole point of the tunnel is to be able to check things out in a safer environment than in the sky. Obviously there are walls to smash into, but all sorts of people are advised to get tunnel -- like people with flexibility issues, physical disability, older age, returning from an injury, etc. Often that's about doing basic skydiving things like staying stable, basic belly maneuvers, and being able to pull, not whether they can join a 4 way freefly style team in the tunnel. Heck, one local jumper here in Ontario got free tunnel time from worker's compensation, because his screwed up landing that broke a lot of stuff, was on a working camera jump. He still can't lift one arm much above his shoulder but flies ok. To the OP: Anyway, it sounds like general purpose legal disclaimer & warning stuff. Contact your local tunnel to find out what they really think about working with someone with a prior shoulder dislocation.

Tests have been done over the years but little by individual jumpers as opposed to companies. Just whipping this post off: While GPS data is easy to get these days, you would still need to do some analysis to get good data out of it. It is hard to find "no wind" conditions all the way up to altitude, so you are going to have to take data acquisition runs in different directions, ideally up and down wind, to help calculate out the wind's effect. Plus, for any observed rates of descents and airspeeds, you'll want to do all your tests in similar conditions to avoid density altitude effects messing up your numbers. At least if you measure on a similar temperature day (across the air mass and not just on the ground), and at similar altitudes, you could compare canopies, even if they are not the 'proper' numbers as one would have for an airplane. That is, airplane flight data is always adjusted to be what it would be at sea level, International Standard Atmosphere conditions (29.92"Hg, 15 deg C), that sort of thing. So if measuring canopy speed and rate of descent at 6000' on a hot summer's day, it'll be faster than if measured at 3000' on a cooler day, in a predictable way. If all this goes over one's head, then one isn't ready to do accurate comparisons of flight characteristics of different canopies. ... Still, it can be fun to go up and get a little data just for fun, comparing different canopies for some rough numbers. Back 15-25 years ago I did a bit of data collection on a few canopies of the era, using a calibrated anemometer, electronic variometer, and a whole bunch of data reduction (analysis) to take into account density altitude effects. So the canopy types are a bit old now! -- and I'm not including modern competition style swooping canopies like a Leia or Valkyrie. This is a very quick summary that I used in a canopy flight course I have sometimes given, to give people some "rough numbers": From my testing. (These numbers have been adjusted to sea level standard conditions... because that's how it is done in aerospace engineering for comparing airplanes in a standardized way. On a typical summer day at a typical dropzone, at a typical height above sea level when flying one's canopy, the air density will be somewhat less. The Glide Ratio won't really change, but the Airspeed and Rate of Descent will be a little higher.) - Glide ratio typically: (brakes off) 3 student canopy 2.5 medium modern ZP canopy 2.1 small canopy In partial brakes, my Icarus FX 88 at 1.9 loading went 2.1 to 2.8! (lowered the rate of descent a lot, while only moderately reducing the speed) (While big F-111 canopies might just get less glide angle with brakes, with less effect on their already slow descent rate) (Sabre 1 135 when adding brake: got only bit better glide ratio with a bit of brake, then a lot worse as one got into heavy brake). Different designs could be more efficient… e.g. a special experimental high glide ratio 11 cell 170 from PD over 20 years ago that I jumped = 4.5 glide ratio in slight brakes - Airspeed: (Bit more than Forward speed horizontally) 25 mph student canopy 46 mph small crossbrace @ 1.9 loading (Icarus FX) But: Deep brakes only 25 mph - Sink rate: 800-1000 fpm big canopy (13-17 fps) for students or novices (On the lower side of that for modern ZP student canopies compared to ones like F-111 Mantas) 1300 fpm Sabre 1 135 @ 1.25 loading 1750 fpm (29 fps) small crossbrace @ 1.9 loading (Icarus FX) In brakes any of those down to only 750 fpm (So one can have the case of an instructor under a crossbraced canopy, maybe not a modern competition style one, being able to almost stay with a student or novice flying full speed under their rental canopy.) Note that glide ratios are only partially affected by the design of the canopy itself. Certainly a fat Parafoil with giant nose openings will be draggier than a modern highly elliptical swooping canopy with small nose opening and crossbraces for holding the shape well. Much depends on the trim the designers have chosen, nose up or nose down. That's why many swoop canopies are so 'ground hungry', trimmed nose down for more speed to use for a long swoop & flare, not just floating around in the sky. Another big factor is jumper size relative to the canopy. Scale the same parachute design down, and keep the same sized jumper under it, and now that jumper is in effect a larger draggy object below the canopy, dragging back from under the canopy even more as the speed increases with a smaller canopy. I saw some manufacturer test data way back that certainly showed the effect: Same canopy design at the same weight had a much worse glide ratio as it scaled to smaller and smaller sizes. - The PD info in a youtube video that BMAC posted is good, comparing a Pulse and Katana 150 at the same loading. Note that it looks like the data hasn't been adjusted to sea level standard conditions -- it is just the data they got that particular day and speeds would be slightly faster than in my type of data. Still a great comparison -- You can see how with brakes set, the Katana and Pulse are only somewhat different. Pop the brakes and now the Katana is super ground hungry in comparison.

Even if the camera isn't a snag hazard: a) national skydiving organizations often forbid cameras on less experienced jumpers (even if the person is strapped to an instructor) and b) there's no incentive for skydivers and dropzones to take away from their own revenues in providing video services to tandem students. It is what it is. Enjoy your jump. Hopefully you do get video. :-)

Curiously, their current Vortex / Decelerator manual has no mention of, or instructions about the number of reserve pack jobs or any porosity checks. Then one can get into the arguments about "What instructions from a manufacturer are the official instructions a rigger must follow?" I'm sure many would argue that something printed on the reserve parachute itself constitutes an official instruction, even if "it's not in the instruction manual".... Does Parachute Systems currently answer messages or are they now completely gone, despite the website being up? For a while in the last couple years, various people around the web said they were still supposedly open for spare parts sales & manufacture but not whole rigs & canopies....

"Survey says...", I mean, my old ParaGear says: Raider = 220 feet in their 9 cell range of canopies (unlike the Fury), supposedly 484 packing volume (although those numbers can be uncertain). If your rig is a Vector II, then attached is a pack volume chart. Although modern canopies don't always have volumes listed any more, so it isn't necessarily a great help in figuring out what modern canopy will fit in the rig. What you should be flying, both initially and as you get experience with ZP canopies, is a whole other thing. 09101 (Vector II sizing chart).pdf