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mark last won the day on February 14

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  1. US patent 8,074,934 B2, 13 Dec 2011. Also, French patent 2 706 855, 1993. I'm not a lawyer, and I don't know if US companies are required to honor non-US patents. I also don't know if this patent has expired. --Mark
  2. "This force evaluation is measured in exponential exertion."
  3. This rig comes with a MLW-mounted hook knife standard.
  4. I know people like that, too. A label that says "put lines here" is not sufficient for stupid. Twice, eh? DIdn't figure it out the first time?
  5. Not exactly. Depending on when the disconnection occurs, it's possible to launch the bag with enough momentum for the lines to pay out and for the bag to open without the help of the pilot chute.
  6. No. You get to the "V" stage when the reserve bridle is first stretched from the bag to the MARD, as the bag is lifting out of the container. The MARD needs to stay connected until the canopy is out of the bag. After that it doesn't matter much if it remains connected or releases, except it's nice if it remains connected to the main -- easier to find everything.
  7. During a MARD deployment, just as the bag is lifting off, the MARD device is pulling on both the bag and the more-or-less inverted reserve pilot chute. The bag/canopy has mass, the pilot chute has mass, and both legs of the inverted "V" of the bridle stretch and recoil repeatedly. The masses are different, and the legs are different lengths, so the magnitude and period of the recoil oscillations are different. If the pilot chute leg loads while the bag/canopy leg unloads, the MARD device disconnects. This is the case for all MARDs in common use, except the Infinity MARD.
  8. So after a week of back-and-forth emails, here's what I have: A porosity test is required. Anybody with a porosity tester can do the test. There are no special qualifications for the tester, no calibration standards for the equipment. The porosity test must be done at least twice (to get a "mean average"), but maybe more, one of which must be the center cell. All the tests are "normally" done 12" from the nose on the top surface. If there are normal places, there must be alternative places, but these are not specified. The center cell reading can be an indeterminate amount higher than 3 cfm, as long as the average is 0-3. If the average is higher than 3, there's nothing to prevent you from doing additional tests until you can get the average down to 3 or lower. If you are happy with the results of your inspection and the porosity test, you can put the canopy back in service for at least one pack. After that, additional packs/jumps might be authorized, but I never got an answer to repeated questions about the correlation between porosity test results and additional packs/jumps. No new scorecard on the canopy required, so no way for the next rigger to know if the porosity test was done or what the results might have been, or how many additional packs/jumps might be authorized. Findings should be recorded on the data card, even though there is no data card retention requirement in the US, and the data card is not a maintenance record in the US. Findings should also be recorded in the rigger logbook.
  9. Ok, I could do that. How should I translate their results into additional packs/jumps? And do I need to sew another scorecard on the canopy?
  10. Please share email address. Thanks.
  11. Parachute Systems Decelerator reserve scorecard is full. If it were PD, I'd send it back for recertification. What to do with Decelerator?
  12. Maybe for some people (though the OP considered it and decided against). Just know that landing on rears with intact brake lines is different from landing on rears with no brake lines.
  13. Actually, I was thinking of $500 as the down payment. Your time is more valuable than that. In your area, see what Chuting Star charges, and consider what MEL, Dave DeWolf, Kirk Smith, Tom Dolphin, et al, charged or charge, closer to $1500-1800 exclusive of testing.
  14. I'm happy to share all the materials I developed for the US Academy of Parachute Rigging, no charge except for acknowledging the source. As for "mentoring," consider asking for, say, $500 per interested student, as a way to screen for those who are willing to make a commitment and will be a joy to teach.