jmidgley 0 #1 September 28, 2004 Can anyone settle a debate with some facts? I'm looking for some data on likely injury/surviveability with increasing vertical descent rate. Of course if the data supported my position, that would be fine, but I'll protect the last vestiges of my intellectual honesty by not saying what that position is... Regards John Midgley Quote Share this post Link to post Share on other sites
DanG 1 #2 September 28, 2004 Are you talking about the landing? If so, it seems obvious that injury/death is more likely upon landing if your vertical descent rate is anything much more that zero when you set your feet down. Maybe I misunderstand the question. - Dan G Quote Share this post Link to post Share on other sites
jmidgley 0 #3 September 28, 2004 Mmmm... Assuming a vertical descent onto solid flat ground, such as might be experienced by someone under a round non-driven reserve, or someone stepping off a wall. In the latter case (unless it's an awfully high wall) the subject would be accelerating, but given the height of the wall it's easy enough to work out the speed at the moment of impact. In ideal conditions, the reserve would have a fixed descent rate. So the question is, is there some received wisdom (from the military, say) about the likelihood of injury or death as speeds increase. I'm thinking of something like[1]: 10 feet per second (equivalent to 1.5' wall)- no injury 16 fps (4' wall) - small proportion minor injury 20 fps (5'9" wall) - large prop minor injury 32 fps (16' wall) - dead as a door nail The 'impact' goes up with the square of the speed too, I'm sure. Anyway, that's the kind of thing I'm after. John [1] Numbers illustrative only! Quote Share this post Link to post Share on other sites
councilman24 36 #4 September 28, 2004 As a medical first responder we treat any fall from a standing position as potentially life threatening. So, velocity of feet or head? Any information would be only anecdotal. As in, I've seen people break their leg stepping off a curb and I've probably walked away from 25 fps in the peas.I'm old for my age. Terry Urban D-8631 FAA DPRE Quote Share this post Link to post Share on other sites
jerry81 10 #5 September 28, 2004 QuoteAs a medical first responder we treat any fall from a standing position as potentially life threatening. So, velocity of feet or head? Any information would be only anecdotal. As in, I've seen people break their leg stepping off a curb and I've probably walked away from 25 fps in the peas. I agree. People manage to kill themselves falling off chairs. On the other hand, I personally know two climbers who dropped off +30' walls and survived with nothing more than serious bruises. Quote Share this post Link to post Share on other sites
kelpdiver 2 #6 September 28, 2004 Quote 10 feet per second (equivalent to 1.5' wall)- no injury 16 fps (4' wall) - small proportion minor injury 20 fps (5'9" wall) - large prop minor injury 32 fps (16' wall) - dead as a door nail In that range, trying to stand it up versus PLF'ing makes a big difference on the injury potential. I'm not sure how big a variance there is for jumpers based on their bone/muscle mass versus their ideal weight. Quote Share this post Link to post Share on other sites
namgrunt 0 #7 September 29, 2004 as an older military jumper many years past t-10 round, 200lb body weight ,75+lb stuff + rig under perfict canopy with little wind was thug, ug, hurt, but you get up. plf on the outher hand hard to plf backward you lat there sooo face the wind you young folks really do not know how great this sport has gotten,not easier mind you but modern equipment makes ALL the differance in the game I just did my aff level 1 after 30+ years since last jump ,old bones,gray hair ,flab all the stuff you have yet to look forward to.hooah love it but hope to never know the answer to your question59 YEARS,OVERWEIGHT,BALDIND,X-GRUNT LAST MIL. JUMP VIET-NAM(QUAN-TRI) www.dzmemories.com Quote Share this post Link to post Share on other sites
mjosparky 3 #8 September 29, 2004 For what its worth. Canopies manufactured under TSO-C23d are required to have a decent rate no greater than 24 fps. In the Operational Requirements Document for the new ATPS, they call for a decent rate no greater then 16 fps with a 300 pound load. SparkyMy idea of a fair fight is clubbing baby seals Quote Share this post Link to post Share on other sites
jmidgley 0 #9 September 29, 2004 Aha! Thanks. I imagine that there's some research somewhere behind those figures - unless they plucked them out of the air... Regards John Quote Share this post Link to post Share on other sites
mjosparky 3 #10 September 29, 2004 QuoteAha! Thanks. I imagine that there's some research somewhere behind those figures - unless they plucked them out of the air... Regards John Its called testing........drop testing and live testing.My idea of a fair fight is clubbing baby seals Quote Share this post Link to post Share on other sites
