• Content

  • Joined

  • Last visited

  • Feedback


Everything posted by dgw

  1. dgw


    I think that is right. I think a lot of historic wars (in Ireland) were about having a war to lose the least amount of resource, knowing that sooner or later a war was going to happen. No nukes, of course.
  2. I have no dog in this fight at all. If the bone is real however, I say pick all the meat off it and fully expose the bone. It seems to me that this issue could be tested by any competent rigger with access to similar harness-container / parachute combinations. I don’t think this website caries the weight it once did in informing people by skilled, knowledgable, and esteemed peers. I do think, however, that Aerodyne should answer this challenge for the purposes of both finding the issue (whatever it is) in the complainant’s video and, assuming the bone is clean, protecting their reputation.
  3. Yes. That is what I thought Coolbeans more or less had in mind. I noted your comment responding to me but I couldn’t reply earlier. My thoughts were that, for this sort of idea, more thread / stitches = less riser stretch over a bit longer time than in a normal deployment. That was it. The injury risk is not just acceleration related, but duration related.
  4. Here is a study on fall arrest harnesses / acceleration / impulse published by the UK Government’s Health and Safety Laboratory. I think it touches on your idea, and might help. https://www.hse.gov.uk/research/hsl_pdf/2003/hsl03-09.pdf
  5. You might want to have a look at some of the injury tolerance research. It might help with understanding the relevance of the opening deceleration and impulse to risk of injury. https://humanresearchroadmap.nasa.gov/evidence/reports/Occupant Protection.pdf Here’s an extract setting out some relationships between deceleration, impulse, and injury:
  6. I might have missed the point entirely here, but it seems to me that Mr Beans had an idea that ‘fall arrest’ type risers might ameliorate opening acceleration, not by stretching of the risers, but by failure of the thread in the stitching in the sewn parallel ‘accordion’ of webbing. So, I don’t think his idea needs metres of webbing, but it might need meters of thread. $0.02
  7. I expect that they would all just coalesce into one group of magnets in the pack job. That might hinder the slider opening correctly, and therefore hinder proper opening. My $0.02
  8. Two minor things. Clicking on a fully open thread does not open the thread, it just reloads the sub forum. When one opens a thread with new posts, the first new posters name is off the top of the screen. One has to scroll the screen down to see who the poster is (if one doesn’t recognise the posters avatar) and then read the contribution. This is what it looks like on a random pick: It’s a minor thing but it niggles me a little. I echo the thanks offered above for the effort put into this site improvement.
  9. Agreed. I am very much pro RSL / MARD. However, people should arrive at their own informed view. My issue in that regard was that the coach was promoting the no-RSL rig as superior equipment, without at least covering the pros of RSL / MARD rigs.
  10. They can be money well spent, but I sound a note of caution. I have attended on two occasions such courses in the UK by a known outfit. On one occasion, the advice for getting back from a long spot with a tail wind was to make oneself as large as possible so that the tail wind would push one more efficiently through the air. I challenged this and eventually prevailed, but only temporarily - by the next day, he had thought about it further and reverted to his former understanding. That advice has also been given by a well known diminutive coach, I am reliably informed by a former team mate. Secondly, attendees at the second course were encouraged to use ‘clean equipment’, by which he meant rigs with no RSL or MARD for reasons of getting stable etc, without at least acknowledging the potential pros and cons of both philosophies. For newer skydivers, this is poor practice. Caveat emptor, and those that fly with them.
  11. I note the same. I’ve used the site on desktop, mobile phone and tablet since the inception of the new site. All devices are fewer than 24 months old and are up to date on operating systems. On the iPad, and the windows computer, each time I click on a link, the secure site padlock disappears, there then follows a pause of a few or up to twenty seconds, and the ‘secure’ padlock reappears. As soon as the padlock appears, service is normally quick. I also miss the ‘how many new posts’ red number. That was the most useful part of the old presentation format in my opinion / usage. Many thanks for the effort put in to this.
  12. I have a V348 with a Smart 150 and a V348 with a PD160. The Smart is a much more comfortable / smaller fit than the PD160.
  13. The attached is from the PD Horizon manual. I'll leave the physics to Yuri.
  14. I think the physics of what you say is difficult to refute. I agree with the idea. Safe implementation might be a practical issue, but implementation of the 'standard' method is also potentially a practical problem. Out of curiosity, I downloaded a PD reserve manual to see what the practice is on (a) reserve parachute. It's a TR-375, which was just the first manual that I happened upon. The attached photograph shows the slider packing method to be ES
  15. Wings listened and they changed the reserve PC design. What about all of the legacy equipment? 6 years of new pilotchute does not cover off a large fleet of 6+ year old Wings containers in the field.
  16. His side flaps look pretty similar to the manual image to me. (I am not a rigger.)
  17. It doesn't have to be. You can use the 'alternative' method and have the kill line window visible.
  18. This is all very strange, but obviously the prosecution didn't do enough to convince the jury of his guilt, certainly not enough to get a majority decision. Here's an article from The Times of 24 November. It sets it out reasonably clearly, in my opinion.
  19. http://www.uk-skydiver.co.uk/cms/files/category/4-manufacturers/
  20. It is either an old Racer or a TSE Chaser, which was (in my opinion) a clone of the Racer. I have one or more Chasers and without digging them out, they are a product of the '80's.
  21. It's an FAR, not a technicality. ***(And couldn't you at least offer to unthread the cutter from the loop without doing a full repack?) I don't do that, I do offer to open (a reserve I packed), remove the AAD, and re-close it. FAA FAR Part 65 and 105 are very short, not much to them. As a skydiver, you should be well versed on the FAR's that cover skydiving. Derek V Having an expired Cypres in a rig, which has been maintained, and not turning it on, is in accordance with the manufacturers instructions. They instruct you not to use it after 12.5 years. I don't think (I haven't checked) that they instruct an owner to remove it from a rig after 12.5 years, just to not use it?
  22. The skydiver and the reserve pilotchute, once deployed, have different terminal velocities. The reserve pilotchute terminal velocity is lower than that of the skydiver. After the transient launch period (and all that goes with that..), this differential (or part thereof) results in the launch force applied to the free bag through the bridle. The launch of the free bag does not require the reserve pilotchute to achieve its natural terminal speed whilst connected to the skydiver. I think...
  23. Unfortunately I could not view the content due to rights restrictions. But, I am sure I can hazard a good guess at the content. The reality is that 'forensic' is a misused word. Forensic means something pertaining to litigation. Forensic science is (or should be) regular, often very basic, science that is used in support of litigation. It is as good as the scientist who does the science. The same applies to 'forensic' accountants, 'forensic' IT consultants, and the whole medico-legal industry.