pchapman

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Everything posted by pchapman

  1. Someone else may have a better take, but I'll take a stab at the issue, although I don't personally know of any cases: Some MARDs disconnect from the pilot chute with almost zero force, and some companies think that is a positive feature. In contrast, the UPT Skyhook MARD is tacked in place, so it takes some pounds to disconnect. That can also be seen as a positive, by preventing unwanted disconnections when the reserve bridle is whipping around in the burble as it starts to pay out. That makes the MARD feature more reliable. I'll now leave that argument aside, whether a MARD should best disconnect at say 0 lbs, 1/10 lbs, 5 lbs, or something else. It may also help in cases of an accidental reserve opening after a main opening -- The Vector pilot chute might not disconnect from the MARD RSL, which in turn is solidly velcroed to the harness, keeping the pilot chute from dragging out the freebag. That's good if you don't want a two out. But in case of a slow speed mal at very low altitude where you did want more nylon out, would that connection hinder reserve deployment? I would expect it to only be an issue in certain rare situations, where the airspeed isn't too much. The Vector PC, while it has worked just fine in huge numbers of uses in some of the world's most popular rigs, is also one that has particularly low drag, so when on a shortened bridle (just to the Skyhook) in the burble of a jumper, it might have a slightly harder time popping the Skyhook seal thread and then extracting the reserve bag from the container and reserve from the bag. How much force it actually takes to disconnect, and what happens in practice under slow speed flight under a main, I'm not sure. (Force to break the seal thread on the Skyhook will depend on actual geometry and knot strength reduction factor, and isn't simply a matter of taking the tensile strength of the thread alone.)
  2. I think we can agree to disagree on this gowler! I can be pissed at some things Boeing or even the FAA did without overdoing it. Some of us more aviation minded people (I'm including you here too) have knowledge about all sorts of accidents, and can put things in more perspective. People didn't stop flying Airbus because two A320's flew into the water with pilots putting in opposing stick inputs (or at least losing any semblance of cooperation) after losing situational awareness after systems failures and then mishandling those systems. (Air France 447, AirAsia 8501, although 5 years apart). It has long been a question about how good it is to have two non-connected sidesticks that can go in opposite directions, losing visual and force feedback between the two pilots both applying controls. It usually works but has its issues. Even if I discount your doomsday scenario, I'm probably being too rational and you have a better insight into people being irrational idiots spooked by shiny things, that happened close enough together in time that they remember both at once...
  3. Well yeah but it takes time. Thanks. One can use the awkward web interface there, or download / extract / filter the MS Access database as I did. The only Parachutes Australia items to show up are: ArticleNumber 6111-( ) [# my edit: that's the Talon 2 licensed copy#] P15 Pigmee S-7 Piggyback Thinpack Parachute Assy S5 and P8 Tandem dual pack S18 Slimpack S3 Trimpig S11 Slimpack II S3 S15 The Talon 2 is under C-23c category B, the rest under C-23b. As you were finding, this does confirm our suspicious that the Airforce reserve isn't TSO'd. As we already know from the bulletin, its life is now considered indefinite. So unless I missed something, an Airforce reserve of any age is jumpable in the US by visiting Aussies, visiting Canucks ("we don't need no steenkin' TSO"), but not resident 'Muricans.
  4. But that's an emergency situation only, not for regular operations. If a skydiver chops their main on a jump, they no longer have a rig that's legal to go jump again intentionally, even when the reserve is repacked. While I don't know aircraft certification in detail, for large aircraft they are always looking at fault trees, estimating failure rates (e.g., 1 in 10^9 hours) and the severity of the consequences of that failure. An Airbus would have degraded handling qualities too, if computers fail and the plane has to be flown in Direct law rather than Normal law. A severe degradation wouldn't be tolerated for release to another flight, but some degradation will be acceptable for emergency flight in the rules if the consequences aren't that severe. So the flight characteristics of a 737 Max might well be considered acceptable in an emergency, with the MCAS shut off. (I'm guessing it would be. It doesn't even need to kick in during normal flight. It just helps with avoiding too high an angle of attack on a plane that is more sensitive to pitch input that on prior models, and with more of a pitching effect from adding or removing power.) But they wouldn't dispatch the aircraft for a new revenue flight with it off. You don't fly A320's without computers, so I'm fine with the idea of not flying B737's without computers. (Even if I also think that the 737 design is getting long in the tooth.) But Boeing needs to have a good handle on failure modes, and how the pilots deal with various failures. It sure helps if the pilots were told what to expect, and not just in that emergency AD in November.
  5. Thanks Jerry. That gets at the 'terminology' issue I had -- how to describe something where the design has a TSO but a particular item, although built to the TSO plans, isn't TSO'd because it wasn't built through production facilities currently approved to build that TSO'd design...
  6. Which makes it sound like it is not actually TSO'd (although I can't tell for sure from this info). It sounds like they used the TSO list of requirements, and did drop tests etc. to satisfy Australian requirements. That could be reassuring to an Australian customer. BUT... the gear wasn't actually entered into the US TSO system. Nor is there any sign that an Australian part 103.18 certification is automatically accepted as equivalent to a TSO by the US. Then you get into the issue, "But what if one is talking about a PA rig that was a license built copy of a US TSO'd Rigging Innovations rig?" That's certainly worth something to a jumper, but if it isn't actually produced in a TSO approved production facility, then it still can't count as having a TSO even if the design is TSO'd. (As a similar example, for one Canadian rig that was TSO'd, it was done through Transport Canada according to bilateral agreements with the FAA, so the FAA accepts it. So it has a real FAA TSO. Then the production plans and facility were approved & inspected so that it was run on a TSO approved production line. Years later, the company owner gave up the formal TSO certification as he wasn't selling many to the US anyway, so it wasn't worth the money to pay for the inspections the Canadian authorities were doing for the production line. A jumper can be reassured that the design actually went through all TSO tests which were accepted by the US, even if a current production rig doesn't actually have a TSO. An earlier rig could be jumped by a US resident, but the current ones can't.) Correct me if I'm wrong about TSO'd production lines -- I'm a bit hazy on that aspect and what formal terminology applies.
  7. Billvon said: I agree some things were implemented poorly. Yeah, autopilot issue, kill it from a disconnect on the yoke, both easy and something pilots are used to. Stick pusher? Not sure of the forces although could be a bit of a fight. Trim problems are worse because if the whole tailplane gets trimmed for nose down, stick forces can get very high and even max deflection on the yoke (if you manage it) might not be enough to recover. It all starts with a failure of the one angle of attack sensor though. Wonder if that was just bad luck, bad sensors, or something else in the system. One wouldn't want to base the MCAS on a particular sensor unless one had some data showing that sensor system is pretty reliable to begin with. Still you should be able to indefinitely play the game with you trimming up and the plane trimming down 5 seconds later, until you remember where the cutoff switch is. Anyway, time to read up some more on understanding the details, on what display issues and warnings the pilots would be faces with, when angle of attack sensors disagree.
  8. I notice digitized copies have been going around. Very handy to have backups to my paper copies. At least the copies are free, even when not legal.
  9. Unless I'm wrong, the system seems to be kind of broken for showing what posts refer to, when made before the format change. In the old way, one would see what someone was replying to, but it looks like all that information has been stripped out, so we've permanently lost valuable information? For example, a header for a reply in the past might have been " Re: [BobSmith99] Cutaway cable length? " . But now if I look at the archives, and I read a reply that says "That's a very dangerous idea.", there's no header at all. So if they haven't expressly quoted the text they referred to, now it could refer to any of the previous posts??!! It used to be clear that that reply was about BobSmith99's idea, but now information seems to be lost. Of course there are no headers on replies made now, but at least one sees that, so one can be more careful about including a quote or referring to what exactly one is replying to.
  10. I bet you'll agree not to necessarily trust witnesses. Some are great, some are crap. Plenty of witnesses have seen "a crash and a fire" but reported "a fire and a crash". If this accident is MCAS related, I'm surprised that the pilots got caught out, given that the FAA AD & Boeing instructions after the first accident should be top of mind. Hit the flaps (if not too fast) or get to that trim cutout switch on the panel between the seats. (Not that I'm entirely aware of all subtleties of electrical and manual and MCAS trim.) Modern airliners have all sorts of refinements / kludges to make them work better / easier than their natural aerodynamics allow. (e.g., Auto trim, yaw dampers, artificial feel, stick shakers, stick pushers) So I'm not fundamentally against some extra add-on like the MCAS system to improve handling. But this has been a wake up call to think more through the automation process (e.g., inputs from one angle of attack sensor, rather than voting with 3 of them) and pilot training. Still I'm surprised at all the groundings, it's like it has gone viral. "We have to ground because THEY grounded..." God knows Airbus has had its issues too when circuit boards fail, pitot tubes clog with ice, etc. Maybe somehow it seems worse or easier to process for people if it is a case of "the plane tried to dive into the ground" rather than "the computers presented the pilots with extremely confusing or missing information.... which the pilots then didn't handle perfectly and caused the crash".
  11. I'm being ninja'd here but I'll still say: Any pressure from above on investigators is a concern, so it remains to be seen whether the following general idea applies here: Don't charge someone with something if there's no realistic charge of conviction. That I think is still a reasonable way to run a justice system in most cases. The opinion was that no conviction would be possible, so it didn't make sense to bring those charges. Looks from the Fox News article like the FBI were trying to be really fair to both sides during the run up to the election, working both the Clinton email and Russia influence issues, without panicking anyone. (Although the James Comey statement shortly before the election on the 'new' emails can be debated both ways.)
  12. This has been hashed out before in big arguments on dropzone. Someone did get a statement from the FAA that it is perfectly legal to pack a rig where the AAD expires before the end of the pack cycle. As others are saying, it is absolutely 100% clear that as a rigger you are not certifying a rig for 180 days, you are certifying a rig to be airworthy at this very moment. If you have liability concerns, then you might as well give up rigging. "I'm sorry, I won't pack for you because you're a bit of a goof. And you might try to deceive your DZ about your rig's airworthiness at some point. And your gear is kind of old; you should buy new stuff, through me. And I don't like the brand. Plus it is ugly. And you have kids and a spouse who might sue if you bounce."
  13. PD is a company that has done a lot of fiddling or research with slider design, and while they have some domed sliders, the variety of slider designs they use suggests that domed sliders are not the answer to every problem. Most PD sliders are flat, but PD uses domed sliders on the Sigma tandem mains. They also have Katana canopies of certain sizes with mesh at the outside of the slider, divorcing the grommet spacing from the actual sail slider fabric size. Those sliders are also domed. They also have canopies with I guess flat sliders, that have snaps to hold the slider in place, and that's whether it is a high end swooping canopy or a giant-nosed accuracy canopy.
  14. Probably pretty hard to find that kind of information, especially in first world-ish English speaking countries & many others. Unless it is some company-internal data at Cypres. Cypres kind of lets people go past the inspection dates and expiry lifetime (and I'm not talking about the newer units with different lifetimes), but I get the impression that was more to accommodate far-off places where such stuff was going on anyway, or units would get stolen when shipped for service, due to a bad postal system. It would be very rare to have past-maintenance or past-expiry units be used in the US / Canada / UK etc as 'here' the company recommendations are considered strict rules. In one publication in 2014 Airtec wrote: " "Airtec, the manufacturer of CYPRES does not recommend to keep out of date CYPRES units in use for life saving activities subsequently and therefore limits the warranty to 12.5 Years (CYPRES-1 - 12,25 years) in total, according to the present knowledge base and safety standards" " Note that is says "recommend". Anyway there may be some places in the world where a few more Cypres' are used past 4 yr maintenance or 12.5 yrs life, other then the ones now authorized to do so. The only accident I can recall that someone once died because their Cypres 1 battery was way overdue for its 2 year replacement and ran out of juice. Not sure of the details but that's hardly relevant now in an era with lower-power electronics and thus batteries that last 4 to 15 years. (Accident was in Canada, mid 90s maybe, novice screwed up. Not sure of how Cyp1's handled low charge, but I guess the device booted up but didn't quite have enough charge to fire.)
  15. Hop and pops count. You are still 'free' as you exit the aircraft, even if you initiate deployment as soon as you clear the aircraft. (Static line, direct bagging, Instructor Assisted Deployment, and drag-offs wouldn't count. But some of that is pretty esoteric and not an issue for you to worry about.)
  16. I don't think this is a big deal in the long run. The USPA would like to get decent feedback from the field. I still think it is kind of stupid to put it into the BSR's as filling out paperwork doesn't seem to be a fundamental part of actually making a safe skydive. So I laugh at the USPA's actions, even while understanding that they probably thought, "But nobody's gonna fill this stuff out unless we really, really try to force them by making it sound super important." But taking the time to look at the SIM, the BSR info actually makes it sound like data collection would fit the mandate. It has stuff like: Maybe a little more feedback communication is OK for the organization to have. Anyway, not my problem really. I'm in the CSPA where we have long had Accident/Incident/Malfunction forms we're supposed to send in for all sort of stuff. (The info does get anonymized and originals shredded.) Any AAD fire would likely qualify, not just on instructional jumps. Yes it is a battle to get people to send them in, and some DZ's are better than others at getting people to submit them. Incident reports are great for annual safety reviews too, internally on a DZ. I'm ready to just move along on this.
  17. In a related note, I'm still hazy on how much collusion (for the purposes of committing an illegal act) is needed to count as a real crime, to what degree things can be implied without full 2-way communication. Sort of like the issues with King Henry II's, "Will no one rid me of this turbulent priest?!" (which led to the priest's murder on the King's behalf), or some Mafia-style statement, "I would be most grateful to anyone who can solve the situation with that guy .... permanently."
  18. Sounds like a Cypres. ;-) (A new one, that is.)
  19. One needs some context there. 1. The bar tack failures, that situation was fixed about 19 years ago, and only applied to certain models. (Mind you, a fixed one is probably not as good as one that didn't need the fix.) 2. The blowing up stuff, that happened at freefly speeds to particularly heavy jumpers. Ok, I don't recall if the weights were above the certified level or just the recommended level. Nobody will argue that a Raven is as strong as a PD, nor do Ravens have the spanwise reinforcements. Still, it isn't something that happens generally. I wouldn't pick a Raven for a high use freefly rig, but wouldn't have any issue with one being in a general purpose rig, as long as it isn't too heavily loaded.
  20. This is largely ancient history stuff, but this reply is based on what I see in my notes from the Argus war era: There were 5 incidents or accidents that I have records of. All but one of which involved the early cutter design. All those cutters should have been removed from service by a service bulletin. The only new cutter involved in an incident was the San Marcos, Texas one, where the investigation found a steel ball such as from a shot bag within the cutter, and with a damaged cutter. The conclusion was that it was the foreign object that prevented the cutter from fully cutting the loop. So the new style cutter with a harder cutting edge never seems to have had any issue cutting the loop (when no steel foreign object was involved). It just seems like nobody trusted the Argus folks any more by that point, so many rig companies (and the occasional DZ) didn't want to give them a chance any more, new cutter or not. It didn't seem to based on any evidence from the track record of the new cutter. Who knows what would have happened had Argus' remained in more common use. It is up for debate whether a device should be banned without evidence of issues with the new system, while at the same time there is a lack of trust of the company as a whole. As for "letting go on climbout and taking down the whole airplane", I'm not sure why the Argus would be likely to activate unexpectedly on the way up. The chance of something going bad on climbout is in my opinion much much higher from other things -- multi-way climbouts, poorly packed BOC's, newbies in general, whatever. I wouldn't be much concerned about some Argus inexplicably deciding to pop while in the plane, and then have the new style cutter for the first time ever hold the rig closed until climbout...
  21. I say no big deal, color the attachments if you want. Yes there is some concern about acidity of markers. At least get a brand name like Sharpie. But I've never heard of canopies falling apart or fatalities from this. Maybe it's an issue if you're trying to get 3000 jumps out of your canopy rather than just 2500, who knows. It's just not high on the list on concerns in skydiving. Although I already had thousands of jumps and was an active rigger, I coloured the attachments on one canopy of mine, as it made packing just a little faster.
  22. > 2. Never go on a date without a chaperone. As a cartoonist wrote, on any date, pretend that Ronan Farrow is in the room too. > 7. Never go to a costume party. I figure I'd just dress up in a suit and tie. "Hey everybody, I'm dressed up as a Mexican! ... businessperson in a suit" or "Hey everybody, I'm dressed up as an Igbo tribesman from Nigeria.... at a business meeting in a city!" Just playing things safe. (As long as nobody is triggered by the implied cultural imperialism of Western style suits.)
  23. And to be clear, discussion of the BSR rule itself seems to be going on at https://www.dropzone.com/forums/topic/265231-uspa-board-meeting/
  24. I looked up what seems to be the topic of discussion, for anyone (like me) who isn't closely watching USPA board meetings: Ref: https://uspa.org/Information/News/uspa-board-meets-in-dallas Edit for sarcastic comment: Although the rule hardly seems to be a BASIC safety requirement at all. Seems to be an administrative / data collection / reporting / paperwork requirement. Fair enough if the USPA is curious about the stats. (Is it just put into the BSR's because few bother with doing other incident reports? Are incident reports supposed to be mandatory in the USPA?) 'Before your jump, make sure to have some reporting forms stuffed in your jumpsuit, to make sure you have a safe jump! '
  25. The original poster may have better luck with some of the WWII recreation groups out there (or whatever they prefer to be called). Liberty team etc. Or someone who supplies them, like NPTC at Dunnellon Florida. Pretty silly 25 year rule though that the Daks over Normandy group have, whether it is their own or some European country's regs.