billbooth

Very true...the first time the Skyhook saves your freebag/pilot chute, it pays for itself. Better yet...everytime thereafter, it pays for a very nice dinner with your significant other. Such a deal... Once again, I shot myself in the foot.

Remember my rule of thumb: 0.4 - 0.7 seconds between pilot chute release and line stretch. Anything slower or faster, and you have a problem.

Did your CENTER locking stow(s) break? If they did not, you DID NOT have a bag strip. I too have never seen a total bag strip without rubber band breakage.

UPT DOES have an "elasticized" version of the "Y" mod on several rigs for evaluation. We just want to be sure it doesn't cause more problems than it solves before we require it. For instance, it could put a disproportionate portion of the opening shock on the spine if the leg straps weren't tightened in the first place, or slipped.

Ditto! Always stow all but the last 12-18" of your lines.

Most major manufacturers have license applications. I will let each of them announce when the Skyhook will be available on their respective rigs.

This scenario has been tested again and again, both on the ground and in the air, and the system works fine. All rigs with the Skyhook will use the same RSL/Collins' Lanyard system as Relative Workshop/UPT, with the same pin. If you want to worry about something hanging up in a bag lock situation, worry about your riser covers. Very often, a bag lock will not open tuck tab riser covers. You will have to do it yourself, either before (recommended) or after you pull your cutaway handle. Here are some general numbers which may interest you: There are over 5,000 Skyhook equipped rigs out there. If we assume an average of just 200 jumps per rig, then over one million jumps have been made on Skyhook equipped rigs. If we use USPA's estimate of one malfunction for every 601 jumps (I think I remember that number correctly.), that means that there have been 1663 reserve uses of all types on Skyhook rigs. Add to that over 150 filmed test jumps done by Relative Workshop and Sun Path, and over 350 Skyhook demos done at DZ around the world, and you get a grand total of 2,160 actual Skyhook uses. At this point even I, one of worlds greatest skeptics and worriers, am beginning to believe that the Skyhook is a pretty damn good piece of equipment.

For those of us who don't know much about TSO testing, is doing 99 tests good or bad? How many are suggested/required? Does additional testing mean there was something wrong with the initial testing, or that a company went above and beyond the requirements (i.e. is more testing good or bad)? All you learn from 99 test jumps is the malfunctions that happen every 50 jumps or so. However, some parts of a parachute system can be almost fully tested on the ground, before the first jump is made. A canopy release or ripcord system are two examples. However, a pilot chute, or especially a canopy, must be proven exclusively by drop testing. It seems to take about 1,000 jumps or so before you can have much confidence is a new canopy design...and then only if it is packed the same way, by the same people, and deployed out of the same rig. The real problem is mis-rigging, and incompatible components being mixed. Because there are nearly infinite possible combinations, it probably takes about a million jumps, under all conditions, before you really find out how reliable a canopy or container system is.

Almost all the rigs on the market today will deploy a reserve in about the same time.

Well then...It seems my life's work has been for nothing.

I still do not see the point. A 6 year old is also unable to appreciate and analyze the risk of riding his parents car - and the number of car-related fatalities is high. I'm not even talking about activities like riding a bike, going to kung-fu class, or even swimming in the backyard pool. Another problem is that every parent has to make decisions for their children. Some of those decisions are fatal, and almost every child injury or death _could_ be viewed as parents negligence. Like if a kid was shot in school, the parents could be accused of neglecting to work harder, so they could earn more and live in better neighborhood with better schools, where the kids weren't shot. Should it be a felony as well? If no, how could you make a difference? The real point here has nothing to do with safety. There is simply NO insurance available for drop zones and gear manufacturers. The only thing that keeps us in business, and therefore YOU skydiving, is assumption of risk agreements (waivers). Children (under 18 in most states) cannot sign contracts. No waivers, no more DZ's, no more gear manufacturers, no more jumping. It's that simple.

This is interesting, does this mean that if you are using the RSL and have a baglock, that has not released the riser covers, you should manually release them before cutting away? Yes, if you have time.

Yes, (usually) if your main pilot chute is properly designed and fully open...No, if your main pilot chute is improperly designed or streamered. A common cause of a bag lock is forgetting to cock you pilot chute. The streamered pilot chute lifts the bag off so slowly, that the lines blow up over and around the bag. Pilot chutes can also knot up with their bridle. Remember, some people have landed fully open canopies that NEVER opened their tuck tab riser covers.

It is possible with any rig to have a bag lock, or other low drag malfunction, that will not open tuck tab riser covers (which can take well over 30 lbs. of pull to open). You should always be sure that your risers are completely free before pulling your reserve ripcord.

My staff tells me that Parachutes Australia can install Skyhooks now for sport Vectors with Collins' Lanyards already installed.

Simon: Sorry you had a hard pull. However, the Sigma system is not that delicate. While as it says in the manual, I prefer the "good Sigma" ripcord twist, the "bad Sigma" routing only increases the pull force by a couple of pounds. What does make a hard or impossible pull, again as it says in the manual, is routing the ripcord pin down under the main loop washer. Otherwise, pull forces with 450 lbs. suspended weight should be under 10 lbs. (The left handle will always seem "harder" than the right, simply because it is in a more awkward position.) By the way, we do have a military "drogue bundle" double loop which brings pull forces under 10 lbs. with up to an 850 lbs. load.

The evidence looked pretty convincing to me. I came in a sealed container, and was opened at a neutral location in front of me, an FAA observer, and several other witnesses. We were also supplied with video and still pictures from the site, which agreed with the actual condition of the rig as I saw it. If someone played with something, I don't know how.

Sorry. I will get you an answer by tomorrow. Bill

It is probably possible that a collapsed-drogue-bag-lock will not generate enough force to unstrip the RSL velcro on a Sigma. However, that was not the cause of the Guam fatality. The reserve lines were wrapped around BOTH main line groups, just above the risers. This clearly indicates that BOTH main risers were still hooked up when the reserve was pulled.

You are correct. Those are the only two so far. I expect others soon.

It is still in the works. For those that don't remember, I once said that the "snap shackle" is the weakest link in any RSL system. I'll certainly let you know when a better unit is ready.

Guys. All I know is what the magnet company rep tells me. I'll give you his number privately if you wish to talk. We tried a lot of different magnets, with the basic idea of producing riser covers which release with about 5 pounds of force. Whatever the "Gauss" of these magnets, that is what they do, and that is really all I care about.

You know, this is one of the things I had been wondering myself. I am by no means an expert on magnetism or magnets but if I find something interesting I tend to google it. It seems to me that the magnets being used in the new riser covers are very similar to the magnets in which George Galloway had sent around with his paratelemetry devices. When I had asked George about the magnets he told me they were made from a powder and epoxy and then coated. That sounds similar to Bill's magnets. Upon further investigation I was informed that these were made of a Neodymium Iron Boron (NdFeB) Material, which also coincides from what Bill's magnets are made out of. Digging even deeper, I found that most places that sell these magnets grade them as N40, one of the stronger readily available grade of magnets. Still curious, and this is where the uncertainty begins, I began finding manufacturers websites that state numbers as high as a maximum of 40 MGOe (about 40,000,000 Gauss) for the material used to make a grade N40 Magnet. However, it seems that when measured, at the surface of the magnet you'll find numbers less than 13,000 Gauss. They tend to have about a 10lb pull force, obviously depends on the material tested with, and would make sense that they see around a 5lb pull force after sewn into a rig. Bill has said he's tested these in all the scenario's he can think of and the only side effect so far was a variation in magnetic compass heading in the front position of a small jump plane. He's given his input on DV tapes, pace makers, etc. It just struck me as odd when he had mentioned such a low gauss with these magnets. Sorry guys. What I referred to is surface Gauss mesurements of 35 HUNDRED Gauss. We just say "35 Gauss" around here to make it simple.

What struck me was how little "new stuff" there was. I guess that means that things have stabilized for a while gearwise...which might actually be a good thing. Our big problem, if we have just one, is not gear related...it is people, or training, related.

The pin is the same one we've been using for the past 15 years. It looks something like a standard hand deploy pilot chute curved pin. It is stamped out of a solid plate of stainless steel...no joints. The new ripcord simply loops over it. There must be a picture of it on the UPTVector web site somewhere.