jumperconway 0 #1 August 7, 2003 I didn't post this in incidents but I think it is well worth reading by all. I replyed to it. Pilot-chute packing & extraction force Quote | Reply -------------------------------------------------------------------------------- An incident at my local DZ that resulted in a routine reserve ride got me thinking about pilot chute packing. There's one aspect of it that isn't always appreciated. A jumper with perhaps 100 or 200 jumps was unable to extract her BOC pilot chute last weekend at my local DZ. As she had planned to open quite high, she tried to extract it for some seconds, before activating her reserve at a safe altitude. On the ground, it took an estimated 25 to 30 lbs. of force to extract the PC from the BOC, pulling straight outwards. The problem was caused by a combination of two things, either of which is not a problem on its own. The BOC pouch's mouth had a very strong, stiff elastic in it. The mouth wasn't too small, but when stretching it open, it took more force than on many pockets. On first glance, the BOC would be considered very secure and safe for freefly. When a PC is packed, the result can be either one or two rolls of fabric, depending on how it is packed. (End-on views are (a) and (b) of the drawing attached.) The PC can be inserted into its BOC pouch either with the roll upwards (c) or roll downwards (d). The latter drawings are slightly exaggerated examples showing the pilot chute handle sticking out beyond the rolls. When the roll is placed facing up as in (c), the pilot chute extracts much easier than in (d), where the downwards facing edge of the roll catches on the mouth of the BOC pouch. It was a situation like (d) that caused the high pull force in the incident mentioned -- when combined with the snug and secure pouch. Packing with the roll catching on the mouth of the pocket also makes it more likely for the pilot chute to bunch up if poorly folded. Although rolling the PC into 2 rolls is more symmetrical, for me personally, creating just one roll makes it easier to keep the PC really tight. My opinion is that neither packing "roll up" or "roll down" is on its own right or wrong. It depends on the size of the pilot chute and condition of the pouch, whether one wants less force or extra force when trying to pull out the pilot chute. It's something to consider for a moment when one is about to stuff a pilot chute into its pouch. (Background details on the incident: The BOC was a replacement pocket, source unknown, which had been on the container about a year. The gear was a Vector II. The jumper in the incident had only owned the rig a short time. For this jump, the main and PC had been packed by a quite experienced packer. I don't know whether he had packed that particular rig before or not. It was easy to replicate the problem with a normal quick PC pack job, stuffing it in with the roll facing downwards.) Peter Chapman Ontario, Canada (This post was edited by pchapman on Aug 5, 2003, 1:42 PM) Attachments: pilot chute packs.jpg (17.5 KB) Quote Share this post Link to post Share on other sites
jumperconway 0 #2 August 7, 2003 This was my reply to Peters post. If interested in the origanal, see incidents. Conway Hi Peter, I will have to disagree with this post as I have seen a hard pull exactly packed the way that you say and I will explain. I had a friend with over 1000 jumps go silver because a hard pull packed by a packer. The reason for the hard pull was because of the pilot chute being packed as you suggest. The tight elastic on the container hung up on the stitching on the hackey on the pilot chute. I always pack the "soft" side of the pc towards the ellastic so that there is NOTHING for the elastic to grab at pull time. I displayed this to the jumper in question and there was total agreement on the cause of the hard pull! This had a lot to do with the tight elastic on the BOC and the long stitching on the PC. I am sure of the testing we did in this scenario and it may differ from your's, but I will continue to pack my "soft, folded side of the PC towards the elastic" for safeties sake, and always check the PC before I leave the plane to be sure that it's coming out "free" before I leave. Peace and blue ones, Conway 1453 If you're gonna be stupid, Don't get ignorant about it! Quote Share this post Link to post Share on other sites
mjosparky 4 #3 August 7, 2003 How do I open the attchments?My idea of a fair fight is clubbing baby seals Quote Share this post Link to post Share on other sites
okalb 104 #4 August 7, 2003 Take a look at this method http://www.bigairsportz.com/pilot-chute.php There is much less chance of a horseshoe by packing your pc this way. If your main pin were to pop prematurely, there is a good chance the pc would automatically be extracted on its own. -OKTime flies like an arrow....fruit flies like a banana Quote Share this post Link to post Share on other sites
jumperconway 0 #5 August 7, 2003 The attachments are in incidents forum. Quote Share this post Link to post Share on other sites
mjosparky 4 #6 August 7, 2003 QuoteThe attachments are in incidents forum. Thank You!My idea of a fair fight is clubbing baby seals Quote Share this post Link to post Share on other sites
