pchapman

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pchapman last won the day on February 25

pchapman had the most liked content!

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253 Excellent

Gear

  • Main Canopy Other
    75,88,135,154,265,265,282, & some rounds
  • Reserve Canopy Other
    2* PD143, 2* Phantom 24, Baby Cobra
  • AAD
    Cypres 2

Jump Profile

  • Home DZ
    (Ontario, Canada)
  • License
    D
  • License Number
    1014
  • Licensing Organization
    CSPA
  • Number of Jumps
    3900
  • Years in Sport
    30
  • Freefall Photographer
    No

Ratings and Rigging

  • Tandem
    Instructor
  • USPA Coach
    No
  • Pro Rating
    Yes
  • Wingsuit Instructor
    No
  • Rigging Back
    Senior Rigger
  • Rigging Chest
    Senior Rigger
  • Rigging Seat
    Senior Rigger

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  1. Here's all mine. (Did you get yourself a 'dactyl?) Paradactyl Manual (slightly expanded version).pdf Paradactyl - shorter Guardian manual [P Chapman scan from M Stevens copy].pdf Paradactyl manual (DactylManual)[M Stevens scan].pdf
  2. A tip -- If you can turn off Javascript and refresh, most WaPo articles can be viewed. (Depending on the browser & operating system, that can be very longwinded to do, or easy to do with some browser extension.)
  3. From BasicOne's posts, I get the idea that the M2 cutters are like this: a) The old ones had the "flat plate plunger" design that shears the loop at both cutter holes. Something not at all known to the public before, I think. Quite a different design. b) Then I guess after Airtec/CYPRES' patent expired on single blade cutters, newer cutters use a single blade like a Cypres. That the kind BasicOne did tests on, using 2019+ M2 cutters, and was concerned with the amount of damage to the cutting edge after firing.
  4. Boy this brings back memories of the AAD wars from a decade or more ago! As far as I recall, this is how I'd put this into context compared to the other AAD companies: Cypres always had the hardest, best cutting cutters. Vigil has the circular cutters (effectively 2 blades), that they tout as being a good concept, but have come under some criticism, even though they generally do the job. (eg, one serious critique in "What's going on with AAD's" by Kirk Smith, 2011) Argus had serious cutter issues. They also used circular cutters. (I got the impression that was due more to a Cypres patent in the early days?) Most issues were actually with their older style cutters, before upgrades in hardness & manufacture, but in any case the tide turned against the company and their AAD's are pretty much irrelevant now. Mars M2.... don't recall hearing of cutter issues before (for actual cutting), but never saw any engineering data on their cutter hardness. (There was one accident relating to their very old MPAAD design, not the M2.) Someone should ask Mars about their M2 cutter hardness. That's just one measure of goodness, but a decent one. I would still have to dig up info on other designs, to see what metal hardness values were found for other companies. .......Hmm, here's something I had on the Argus vs. others: (My interpretations of the Polish report on the fatality there in 2009 that involved the Argus.) So, I wonder what an M2 cutter is like. Great testing by the original poster, BasicOne, thanks, but I'd like to see independent confirmation too! [Edit:] After all, the M2 has been reasonably popular in recent years too, and surely cutting loops successfully, even if not out there in number like Vigils and Cypres'.
  5. Sorry, can't be true. I don't know anything about what may have gone on in the background, but the canopies are very different. Excalibur wasn't tapered -- Adding taper was a huge change in canopy design complexity! Excalibur had different nose inlet shapes. Different standard sizes. The Precision built FX's were of course licenced from Icarus in NZ. Maybe that's what you were thinking of? (I still fly an FX but don't know all the history from back then!)
  6. Space X uses Pioneer drogue parachutes for the return of their Dragon spacecraft. (But Airborne Systems provides their main parachutes.) High speed parachute design is a specialized thing, so even Space X didn't do it in house. Still got my Pioneer Titan canopy, though it has been a decade since I used it at Bridge Day... Will be interesting to see what happens to Strong.
  7. Interesting. How much of an issue is this in practice? I don't know, but I see the EG18X smoke grenade is on the list as no longer exempted. Its baby brother -- with less smoke volume -- is the EG18, isn't mentioned, so that one is still OK without the extra regulations. I have used the EG18X on demos. A pretty decent grenade for that use, at a reasonable price. Some years back they seemed to be the best I would see available. But in recent years there are pricier grenades out there with higher performance. So I don't know what high end, well sponsored teams use. But for smaller demos, the EG18X's were nice to have. So it kind of looks like the higher end, better stuff, is getting more regulation.
  8. Since this 2018 thread was revived: It is interesting to consider the "two ways to double stow" issue that sundevil777 brought up after Westerly's observations. To recap, there's the "wrap around twice like wrapping it with tape" , and there's "make a single stow, stretch the elastic, make a half twist to create a new 2nd loop, and put that over the line bight". One sees the first method, for example, in one PD tips youtube video. I confirmed that both methods are equivalent topologically in the sense that the final result can be changed from one to the other while the elastic is in place on the lines. If you try it, you can look down at the line bight in its double stow, and move one loop of the elastic over a little and be back to the first instead of the 2nd configuration. Like sundevil said, there's technically no actual knot created. But the 'twist 180' method does seem a more secure or little more grabby, as there's more rubber band overlapping other parts of the rubber band. Whether there's any significant effect on line deployment in practice, who knows. So far I'm not worried about which method I use. I also tend to do the twist 180 method. Which one does will depend on what one is used to , but perhaps also likely on how tight the elastics are when trying to wrap the bights. The simple wrapping method works better for me if there's a lot of stretch in the elastic relative to the position of the lines needing to be stowed. As for Westerly's elastic breakage issue: I may not be imagining correctly what Westerly did. I'm not sure if he meant putting in the 180 twist, or even adding another 180 on top of that, which does change things and make it impossible to simply slide the elastics around once in place on the line bight, to change to the other configurations. That might in effect be 'tighter' and put more stress on the elastic when the bight gets yanked out of it.
  9. Lines out of trim. (If they are the kind that go out of trim. Any Spectra in there,as main lines or brake lines?)
  10. Still F-111 if I recall correctly. An invention a little ahead of its time, just waiting for ZP to arrive...
  11. Paragear 1991-1992 catalogue, the first with the Cypres in it: Cybernetic Parachute Release System (Cypres) $1225 (In current dollars, that's $2770) (Compare to Cypres 2 price at Paragear now, over 30 years later: $1199, less than the original dollar price, with a longer life and no mandatory servicing either.) Also in Paragear that year: FXC AAD $695 (A lot less than the Cypres, but its 2 year factory checks added up too, for the diligent DZ's that did them.) RWS Vector II $978 (Cheaper than the Cypres) (In current dollars that's $2210.) (Vector III at Paragear now is $3350, over 50% more despite accounting for inflation, although it certainly does have a few more features than a Vector II. Still just certified as a Wonderhog.) [Edit: Inflation calculated online with 1991 average, to Sept 2023, the most current data, for the US CPI]
  12. Lots of things are not 'recommended', or 'unsupported' but are perfectly safe and/or are accepted in the industry. But leaving that aside... One pack volume chart, from Parachute Labs, shows a Tempo 150 at 312 cu in, and a Smart 160 at 416. While pack volume measurements are notoriously uncertain, this does suggest the Tempo is quite a bit smaller in volume. Sounds a bit iffy to me. You could of course just pack it up and have a look, to see whether it is loose in the freebag (and not putting tension on the safety stow?) or makes the rig close up oddly. Would be interesting to know how it turned out. Usually the problem is totally overstuffed rigs (ugly, bulging, poorly fitting flaps & PCs, and hard to close) rather than ones with too small a reserve in them...
  13. I have seen so many stows where the internal elastics are breaking but nothing has seemingly been done about it for ages. So on the one hand I have replaced many that I think should have been replaced earlier, but on the other hand I'm also willing to let things slide to some degree, as it is as if the local consensus is to leave these things a long time. I think riggers don't always try pulling them out a little way just to see what condition they are in. (Or if they are a horribly ugly home job with terrible stitching... every rigging horrors album has a photo of those.) After all, it seems like there's still a ton of strength in the fabric of the stow even if all the internal elastics are broken -- through some combination of stretching over time, and overaggressive sewing when building the stow, that damages a lot of the elastics from the start. I've seen ones look pretty damaged when almost brand new. What I tend to object more to is the state of stretch, whether the stow is getting really stretched out and holding the lines only loosely. Yeah the mass distribution of lines, and accelerated mass of the canopy in the freebag "should" keep the stow functioning, but one does also want the safety of it being able to grip the lines securely when just sitting there. FWIW, I'm also in the old school camp of just sewing them up myself, using 'standard' good quality shock cord material from ParaGear. Rather than snapping to attention and intoning, "That is a TSO'd component! A replacement must come from the manufacturer (unless I have specific authorization from the company to make replacements according to their plans.)" Like a lot of rigging stuff, don't sew them up yourself unless you can do a decent job of it. It can be, I dunno, 10 years before a safety stow is starting to get sketchy, overstretched and losing grip. Some might be less, and start to go after only half that time. It varies a lot.
  14. This is the earliest all digital Javelin manual I have, with the file dated 2004. (not sure when it actually came out.) The next version I have is Rev02 in 2007, because then Skyhooks were added as an option. Javelin Rev01-Issue01.pdf