adamUK 3 #1 July 10, 2012 Hello all, I had a slammer a few months ago that left me bruised but not busted but it did leave me seeing stars. I also have followed the tandem fatality thread with interest ( http://www.dropzone.com/cgi-bin/forum/gforum.cgi?post=4330697;sb=post_latest_reply;so=ASC;forum_view=forum_view_collapsed;;page=unread#unread ) My question is: Does anyone have any data on the loads placed upon the body during opening and for a particularly hard opening what levels would cause serious injury or incapacitation? Has anyone measured these? Many thanks in advance. Adam. Quote Share this post Link to post Share on other sites
Bluhdow 31 #2 July 10, 2012 I got crushed a couple of weeks ago too. This is just an estimate but I'm pretty sure it was around 75 g's.Apex BASE #1816 Quote Share this post Link to post Share on other sites
virgin-burner 1 #3 July 10, 2012 opening shock is known to have torn aortas if that's of any help..“Some may never live, but the crazy never die.” -Hunter S. Thompson "No. Try not. Do... or do not. There is no try." -Yoda Quote Share this post Link to post Share on other sites
VideoFly 0 #4 July 10, 2012 I had a whacker several years ago. The force caused my camera helmet to break through the fiberglass on both sides in the jaw area. My right foot hit my right shoulder and my neck broke into pieces. I now have a neck made of part of my hip bone, a titanium plate, and a bunch of screws. I am partially paralyzed in my right hand and mostly paralyzed in my left hand and arm. I’ve had whackers before, but this was an instant slammer! Quote Share this post Link to post Share on other sites
adamUK 3 #5 July 10, 2012 Quote The force caused my camera helmet to break through the fiberglass on both sides in the jaw area. My right foot hit my right shoulder and my neck broke into pieces. Found some interesting information here though it refers to automotive and aeronautical fields primarily: ftp://ftp.rta.nato.int/PubFullText/RTO/EN/RTO-EN-HFM-113/EN-HFM-113-06.pdf P.S. The severely injured data points are from tests using chimp and pigs. So not much different to skydivers then Quote Share this post Link to post Share on other sites
JerryBaumchen 1,441 #6 July 10, 2012 Hi adam, This guy was on the leading edge for a long time: http://en.wikipedia.org/wiki/John_Stapp JerryBaumchen Quote Share this post Link to post Share on other sites
adamUK 3 #7 July 10, 2012 Quote This guy was on the leading edge for a long time Thanks Quote Share this post Link to post Share on other sites
theonlyski 8 #8 July 11, 2012 QuoteI got crushed a couple of weeks ago too. This is just an estimate but I'm pretty sure it was around 75 g's. Death or serious injury can occur at 25 g's. If you had a ~75 g opening, you'd be lucky to be alive and able to move IMO."I may be a dirty pirate hooker...but I'm not about to go stand on the corner." iluvtofly DPH -7, TDS 578, Muff 5153, SCR 14890 I'm an asshole, and I approve this message Quote Share this post Link to post Share on other sites
JohnSherman 1 #9 July 11, 2012 There is data and understanding about opening forces. It is a complex subject. You can find technical understanding in Theo Kanacke's "Recovery Systems Design Guide". What you probably endured was Line Dump/Strip. This is when the lines are left in you container as the bag is lifted off. Caused by inadiquet line stows. The pilot chute generates about 20 G's as it jerks the bag out of the container. There is a great picture somewhere on this forum where the lines are 3 to 4 inches from the bottom of the bag during lift off. This demonstrates the differential of forces. When this happens the slider drops down the lines before the lines are tight. Canopy inflates with full benifit of the slider. That is why I always rubber band my slider to the canopy. Quote Share this post Link to post Share on other sites
Martini 0 #10 July 11, 2012 He was joking. That's allowed here.Sometimes you eat the bear.............. Quote Share this post Link to post Share on other sites
adamUK 3 #11 July 11, 2012 Quote There is data and understanding about opening forces. It is a complex subject. From what I read on the paper I found it was dependent on not only force magnitude and duration but also direction and the rate of increase of the force applied. I ended up with painful lower back, substantial bruise on my arm and my chin had also bruised my chest at the manubrium. I was lucky I guess considering some of the postings on here. I discussed the incident with the rigger and it seems that a line dump was the most probable cause of the hard opening and it's something that I'll pay a lot more attention to in future. I'll look up the reference you supplied and thanks for the input. Quote Share this post Link to post Share on other sites
Bluhdow 31 #12 July 11, 2012 QuoteQuoteI got crushed a couple of weeks ago too. This is just an estimate but I'm pretty sure it was around 75 g's. Death or serious injury can occur at 25 g's. If you had a ~75 g opening, you'd be lucky to be alive and able to move IMO. Lollerskates!Apex BASE #1816 Quote Share this post Link to post Share on other sites
RiggerLee 61 #13 July 11, 2012 I'm trying to recall but looking back I think I've been pressent for at least four fatalities that were the dirrect result of deceleration injuries. I've seen or have knowlage of other nonfatel injuries includeing one guy that would up a parapligic and another that wound up with a torn liver. I'm not sure if any one has ever kept track of these especally the non fatel ones but it would be interesting. There's some pretty good data outr there on opening shock now. There's been a lot of work with data recorders and load cells. Ask Gary Peek. He was kind of leading the charge on that at one point. LeeLee lee@velocitysportswear.com www.velocitysportswear.com Quote Share this post Link to post Share on other sites
bucketlistpilot 1 #14 July 11, 2012 QuoteThat is why I always rubber band my slider to the canopy. Heard of this before. How is it done?Ian Purvis http://www.loadupsoftware.com LoadUp DZ Management App admin@loadupsoftware.com Quote Share this post Link to post Share on other sites
Lastchance 0 #15 July 11, 2012 I had a slammer once that resulted in a lower igunal hernia. It required surgery. I seen stars on that one. I may be getting old but I got to see all the cool bands. Quote Share this post Link to post Share on other sites
Clouddancer22 0 #16 July 23, 2012 How do you rubber band the slider to the canopy?QuoteThere is data and understanding about opening forces. It is a complex subject. You can find technical understanding in Theo Kanacke's "Recovery Systems Design Guide". What you probably endured was Line Dump/Strip. This is when the lines are left in you container as the bag is lifted off. Caused by inadiquet line stows. The pilot chute generates about 20 G's as it jerks the bag out of the container. There is a great picture somewhere on this forum where the lines are 3 to 4 inches from the bottom of the bag during lift off. This demonstrates the differential of forces. When this happens the slider drops down the lines before the lines are tight. Canopy inflates with full benifit of the slider. That is why I always rubber band my slider to the canopy.D-11672 Quote Share this post Link to post Share on other sites
theonlyski 8 #17 July 23, 2012 QuoteHow do you rubber band the slider to the canopy? IIRC the Vector tandem rig manual has a pretty good description."I may be a dirty pirate hooker...but I'm not about to go stand on the corner." iluvtofly DPH -7, TDS 578, Muff 5153, SCR 14890 I'm an asshole, and I approve this message Quote Share this post Link to post Share on other sites
Clouddancer22 0 #18 July 23, 2012 QuoteQuoteHow do you rubber band the slider to the canopy? IIRC the Vector tandem rig manual has a pretty good description.Hmmm, I just looked at the Vector 2 Tandem Owners Manua;, 2003, p. 29, where packing the main is described and no mention is made of using a rubber band for the slider. Which Vector Tandem Manual do you have?D-11672 Quote Share this post Link to post Share on other sites
theonlyski 8 #19 July 23, 2012 Quote Quote Quote How do you rubber band the slider to the canopy? IIRC the Vector tandem rig manual has a pretty good description. Hmmm, I just looked at the Vector 2 Tandem Owners Manua;, 2003, p. 29, where packing the main is described and no mention is made of using a rubber band for the slider. Which Vector Tandem Manual do you have? Oops, apparently I don't RC!I'll look for where I saw it unless someone beats me to it."I may be a dirty pirate hooker...but I'm not about to go stand on the corner." iluvtofly DPH -7, TDS 578, Muff 5153, SCR 14890 I'm an asshole, and I approve this message Quote Share this post Link to post Share on other sites
Clouddancer22 0 #20 July 23, 2012 Thanks! D-11672 Quote Share this post Link to post Share on other sites
loch1957 0 #21 July 24, 2012 Out of curiosity how much of a role does the jumpers weight play into a hard opening?Avoiding danger is no safer in the long run than outright exposure. Life is either a daring adventure, or nothing.” Quote Share this post Link to post Share on other sites
adamUK 3 #22 July 24, 2012 In 'g' terms (as in 2 g, 3 g), from what I've read, I don't think it makes much of a difference as the deceleration speed appears to be dependent on the mechanics of the canopy/container as it opens (any riggers able to shed any further light on this?). The speed of the jumper at the instant before deployment does make a difference though. However with regard to the force applied on your body. The heavier you are the higher the force (i.e. 1.5g on a 200lb mass is 300 lb force whereas 1.5 g on a 100lb mass is a 150 lb force). Quote Share this post Link to post Share on other sites
