brodg

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Gear

  • Main Canopy Size
    120
  • Reserve Canopy Size
    126
  • AAD
    Cypres 2

Jump Profile

  • License
    C
  • Licensing Organization
    USPA
  • Number of Jumps
    300
  • Tunnel Hours
    10
  • Years in Sport
    3
  • First Choice Discipline
    Tracking
  • First Choice Discipline Jump Total
    200
  • Second Choice Discipline
    Freeflying
  • Second Choice Discipline Jump Total
    100
  1. I want to thank the few people who took the time to point out where my calculations were wrong (ghost47 and Di0) and those who gave their opinion without being fucking smart asses or disrespectful. I must say I’m amazed with how many condescending assholes this forum has, specially coming from such a friendly community (skydivers); you guys must have very sad lives to be so critic and arrogant about everything. Anyway, I just wanted to say that the point of this thread wasn’t to prove if skydiving is dangerous or safe; it was only to show people, using some oversimplified numbers and statistics, that the sport can be very dangerous if you don’t pay attention to security and that safety depends a lot on how you see it. Yes, I made some wrong calculations, but at the end the final percent of my oversimplified and generalized chance of dying if you do 10k jumps throughout your life was 7.3% instead of my initial 7%, so I wasn’t that far off. You guys just got lost in the math and completely missed the point.
  2. You're right, 10k is not representative. But I would say there are way more than 25 jumper with 10k jumps in the US. But, again, if you (the OP) are trying to convince yourself that skydiving is safe using statistics, you 're not getting it. Adding skydiving as a regular activity significantly increases the risks your take. Deluding yourself that it's safe only makes it more dangerous for you, and me, so please get it. Mmm I don't why do you assume I'm trying to convince myself skydiving is safe. If you read my post you'll see that in fact I stated just the opposite: skydiving needs to be perceived as a dangerous activity in order to try and make it safer. Because: "We always hear that skydiving can be a very safe sport, and I truly believe that, but statistics can disagree." I said "skydiving CAN BE a very safe sport", which doesn't mean skydiving IS a safe sport (it depends on how you approach it and practice it). I also said
  3. You're right, 10k is not representative. But I would say there are way more than 25 jumper with 10k jumps in the US. But, again, if you (the OP) are trying to convince yourself that skydiving is safe using statistics, you 're not getting it. Adding skydiving as a regular activity significantly increases the risks your take. Deluding yourself that it's safe only makes it more dangerous for you, and me, so please get it. Mmm I don't why do you assume I'm trying to convince myself skydiving is safe. If you read my post you'll see that in fact I stated just the opposite: skydiving needs to be perceived as a dangerous activity in order to try and make it safer.
  4. Here's the method I've always used: If you have a 1% chance of dying, that means you have a 99% chance of living. So what are the odds of living after one jump? 99%. Two jumps? 99% * 99%. Three jumps? 99% * 99% * 99%. Etc. After 100 jumps you'll get 36.6% chance of living. That means, after 100 jumps, you have a 63.4% chance of dying. That's of course assuming that you have a 1% chance of dying. If, instead, you have a 0.001% chance of dying each jump (1 out of 100,000), then you have a 99.999% chance of living. Over 10,000 jumps, you get 90.48% chance of living. Which means 9.52% chance of dying. Disclaimer: I haven't taken a math class, or significantly used math in my life, for close to 20 years. So I could be wrong. ETA: However, once you get to the 9,999 jump, your odds of dying on Jump 10,000 would still be 0.001%. As would be true with any other jump you do. Exactly! I just read the same here http://math.stackexchange.com/questions/227177/what-is-the-probability-of-an-independent-event-occurring-after-repeated-attempt Thanks for taking the time to clarify this bro. Sorry I used the wrong procedure to calculate the probability (I took statistics way to long ago), but I think the concept still applies. Please correct me if I'm wrong but the numbers should be then: *Probability of dying in one jump 0.00075%, so probability of living is 99.99925% *Probability of not dying in 10.000 jumps is (0.9999925)^10.000 = 92.7% *Probability of dying in 10.000 jumps is 7.3%
  5. So, by your method, if every time you jump you have a 1% chance of dying, then the probability of dying in 100 jumps is 1% x 100 = 100%? To illustrate why that's wrong: What are the odds, when you flip a coin, that you get heads? 50%, right? So if you flip a coin twice, what are the odds that you get heads at least once? (Hint, it's not 2 x 50% = 100%.) Yes, you're right bro.. Lol i was so sure of my numbers I'll correct the math and post the right probabilities
  6. Holy shit! So, 50% of jumpers don't make it to 51 jumps? Hahaha you missed this part:
  7. Completely effed up. Statistically speaking that is. You made the odds cumulative right there and they are not. top I fail to see how I made the odds cumulative. I'll use the same example as above to prove my point:
  8. OMFG I never said the risk is cumulative!!
  9. I never said that if you are on your 10.000th skydive you are suddenly at much higher risk. All I'm saying is if every time you jump you have, for example, a 1% chance of dying, then the probability of dying in 50 jumps is 1x50=50%, which is not the same as the probability of dying in you 50th jump (which still is 1%).
  10. Hi everybody. I was doing some math and giving some thought to the skydiving safety statistics. We always hear that skydiving can be a very safe sport, and I truly believe that, but statistics can disagree. I believe this is because safety depends hugely on how we approach the sport and how conscious we are. However for the sake of this discussion I will forget about this and present my case assuming everyone has the same odds of getting injured. My reasoning is as follows, let´s take year 2013 as an example: 24 fatalities in 3.200.000 jumps, in other words a fatality every 133.333 jumps. That doesn't sound so bad, doesn't it? In fact if you give that number to someone who doesn't jump they might say the sport is very safe. This is because we assume that we have a chance of 1 in 133.333 (0.00075%) of getting killed, and while this might be true for someone that only does a single jump in his whole life, it's not even close for a regular jumper. I want to be an active regular jumper so I wanted to know how this odds apply to me. I assumed an active jumper does around 10.000 jumps throughout his life. If this is the case then the statistics change from 1 in 133.333 (0.00075%) to 10.000 in 133.333 (7.5%). That's right!: If everyone has the same chance of dying per jump and you want to do 10.000 jumps in your life, you have a 7.5% chance of getting killed! How fucked up is that? Another funny way to see it is that by every jump you make you are buying 1.950 lottery tickets, if one of them hits the jackpot you're a goner. We can put it a million different ways, but you get the idea. I don't want to be a fun killer and I know this topic can be tabu for some people, but I think everyone should know how dangerous this sport can be in order to take safety seriously. I said that I would assume that everyone has the same chance of getting hurt, and I want to clarify that this is far from true; if you do things the right way then this odds can be lowered extremely. I saw a video the other day where Rook Nelson said "skydiving is like crossing a street: if you just run across it without looking sideways it is indeed very dangerous, but if you do it carefully it can be a really safe sport" and I couldn't agree more with that. So remember, safety depends only on you, be safe out there and have fun!