mark

Members
 View Profile  See their activity

  • Content

    1,993

  • Joined

  • Last visited

  • Days Won

    2

  • Feedback

    0%

Everything posted by mark

  1. mark
    Try US Academy of Parachute Rigging. --Mark
  2. mark
    Over the life of the rig, that's a difference of approximately $0/jump. Buy what makes you happy. --Mark
  3. mark
    ^^^ This. Also, when you cutaway from a big straight-flying main parachute, your forward speed is around 20mph and your vertical speed is around 10mph. The reserve pilot chute presents its side to the relative wind. No pilot chute has a lot of drag in that configuration, but pilot chutes with more fabric do a little better than those that are 50-50 fabric-mesh. --Mark
  4. mark
    One size fits all! That's also true for: UPT, Sunpath, RI, Mirage, etc. --Mark
  5. mark
    At least one manufacturer is using magnets for a tailgate, so it's possible to have magnets on the canopy. I'm curious how using magnets for slider control would work, though. How would you ensure only particular pairs of magnets stuck together, especially since in the course of packing they could reorient, rotate, or flip? For example, how would you keep slider magnets from sticking to other slider magnets? --Mark
  6. mark
    How would you get the failure point to stay the same for the life of the riser? --Mark
  7. mark
    The main canopy drogue release is not TSO'd in the sense that there are no performance standards for it, the same as there are no performance standards for the main canopy itself. So using a home-made drogue release would not invalidate the TSO. It would, however, be stupid. --Mark
  8. mark
    Suppose the answer were "yes." What would be your next question? Also, supposed the answer were "no." What would be your next question? -Mark
  9. mark
    The weak link in the hanger in a hybrid formation is not the 500-pound 70101-1 friction adapter. It is the hanger's shoulder, which is not designed for a 500-pound extension shock load. -Mark
  10. mark
    It's posts like this that make me rethink my position. Strong 26' Type-2 diaper in a Super-Pro is not as easy as a T-10R. 24' flat in a Strong Pop-Top chest is not easy either. Too old school for you? Try a BaserX chest. As for seats, not all seats are the Strongs you describe. Some are Butlers (which pack like other Butler rigs), some are Nationals (which pack like other Nationals), some are Softies (which pack like other Softies), some are military surplus Navy seats with C-9s that pack like T10Rs. The trick for all is to do it with finesse, which is different than using brute force and swearing. -Mark
  11. mark
    I agree, in part. Except I would suggest no ratings at all. Right now we do not distinguish between rounds and squares when issuing ratings, and we're not killing people. DPREs that choose not to train or test on rounds do not get to issue ratings restricted to squares only. Riggers that graduate from such courses are authorized to pack rounds and yet they don't, at least until they choose to get training they are not legally required to have. Why create restrictions where there were none before? -Mark
  12. mark
    Using your reasoning, it's safer for wingsuiters to jump without a helmet (since there are no or very few wingsuit fatalities involving no-helmet jumpers), than it is to jump with a helmet (since nearly every wingsuit fatalitiy involves a jumper wearing a helmet). -Mark
  13. mark
    This combination would allow forexample intentional cutaway. Anything is possible, and we advance only because some people are "out of the box" thinkers. Consider whether the harness could accept the load. Probably, but harnesses are not tested in this configuration. Also consider whether you want to land on your head. Please get video. -Mark
  14. mark
    Emergency procedure for 3-canopy system with MARD on the first of the two reserves, total malfunction of the #1 (Main) canopy, MARD failure to disconnect when attempting to deploy the first of the two reserves: this results in a pilot chute in tow. Plan A: disconnect the RSL. In freefall. Maybe with gloves on. But this releases the towed pilot chute, hopefully in time. Plan B: deploy the #1 canopy, then cutaway the #1 canopy, hoping for an ordinary MARD deployment of the first reserve and not an entanglement. Except that you had a total on #1 in the first place. Plan C: deploy the second reserve, hoping for a good deployment. Except that the first reserve container is open, and is the first reserve still in the container or has it fallen out and started tangling on stuff? -Mark
  15. mark
    This is the best explanation for what happened. -Mark
  16. mark
    You don't need to get speeds that high. You just need to get cabin air pressure changes that would mimic speeds that high. For example, you could slip an open-door aircraft (like a Caravan), then straighten it out. You might do this if you were making an engine-out approach and needed to scrub off some altitude after arriving high on final. -Mark
  17. mark
    Might be sketchy. Might not. The data panel on a 1990 VTC-II says the manufacturer is UPT (even though we all know it was really made by PD). They came without a bowling-score data panel, so knowing the number of packs and jumps depends on having accurate entries on the packing data cards and having all the cards. Since there's no requirement to retain old data cards, canopy history is frequently incomplete. Solution 1: don't worry about it. If a main canopy had just 7 jumps on it, we would call it new. Solution 2: send it to PD for evaluation. They'll add a new data panel, including boxes to score spares and strikes. In fact, this one may have already been back to PD and had a new data panel sewn on, in which case you'd like to know how many open boxes are left, not how many have been filled -- PD doesn't always recertify for a full 40 packs/25 jumps. -Mark
  18. mark
    A good friend/rigging customer tried this. He settled on a Storm 230 that had been a PD demo canopy. He got a really good deal on it. But it wasn't popular as a demo -- it had only a handful of jumps on it. So it was still a handful to pack, not quite what he had in mind! -Mark
  19. mark
    I never do this. Even with new canopies. -Mark
  20. mark
    To see whether this strategy might work for you, try hanging on a chin-up bar for 4 minutes. -Mark
  21. mark
    IIRC, the problem manifested when the closing loop did not go straight through the cutter. The blade would first strike the top (or bottom) side, causing it to tumble slightly, then jam on the opposite side because of misalignment. For Argus, the size of the hole compared to the diameter of the cutter body is not that different from Cypres and Vigil cutters. I do not recall a grommet strike being identified as an issue in any of the problematic incidents. -Mark
  22. mark
    These two sentences do not go together. -Mark
  23. mark
    Looks like a typical RSL activation to me. SOS would not be any faster. -Mark
  24. mark
    Not sure if PD is using this exception, since the exception requires a note on the container, not the reserve itself. But the exception is saying the reserve glide ratio with brakes stowed is greater than 1.12, mark the container and set the max weight for descent rate alone. Do sport containers contain such text by default (I can't check mine right now)? Jerry was in ahead of me. (Thanks!) Your quote is indeed from TS-135v1.4, the standard for TSO-C23f. However, the FAA did not agree to Method 2. See page 5 of the attached cover letter. -Mark TSO-C23f.pdf
  25. mark
    PD Optimums are certificated to the standards of TSO-C23d/AS 8015B. These documents are included in the appendices to the 2005 Parachute Rigger Handbook, I think still available online as a free download. TS-135 has the standards for TSO-C23f. -Mark