billbooth

Let's say that you have a main horseshoe malfunction, and you are going to have to dump your reserve up through it. Now let's say you have not one, but two reserve pilot chutes on your reserve bridle, which are connected so as to form a letter " Y ". What are your chances that that " Y " shaped junction, with a pilot chute on each upper end, is going to make it up through, and past, your main horseshoe. Not very good, I think. Do you really still want a Catapult?

Question: So why do we have 2" bridles in the first place? Answer: Para-flite started it over 20 years ago. When they came out with the first square reserve, the Safety Flyer, they decided to "tinker" with a lot of other things too. The "free-bag" with its bungee "safety stows" and 2" wide "anti-horseshoe" bridle was the result. The Safety-Flyer was marketed with the Swift container system which had no pocketed corners. As a result, when you pulled the ripcord, the bag would simple fall out of the container. When they drop tested this combined system with a built-in "horseshoe" malfunction and a tumbling (unstable) dummy, the bag would simply be ejected from the container because of centifugal force (angular acceleration) and be pulled to line stretch by the force of the relative wind on the bag. The super long bridle allowed the lines to unstow, and the freebag allowed the canopy to open. The 2" width merely provided stabilization so that the bag did not tumble through the lines as they unstowed. The anti-horseshoe system worked in those test conditions. However, as stated earlier in this thread, it will not work with a stable jumper using a modern piggyback system. The long, wide bridle has persisted out of inertia. i.e. No one wanted to go against an existing, "proven" system. Even though, I suspect, the wide bridle helps create and lengthen pilot chute hesitations, because of the drag it creates in the burble right above a stable jumpers back on initial pilot chute launch. I have made one change recently, however. I had to shorted the bridle a bit to make the Skyhook work correctly. I kept the 2" width because of the stabilizing effect I noted above.

The pull generated by a 2" reserve pilot chute bridle in a horseshoe configuration is about 2 pounds. I published a video recording that fact about 20 years ago. Reserves weigh at least 5 pounds. Plus, all modern reserve containers add a "containment" force to keep the reserve bag in the container during pilot chute hesitations, to prevent out-of-sequence deployments (which, by the way, have killed several jumpers using older containers without this safety feature). So, it usually takes at least 10 pounds of force to remove a reserve bag from its container. Therefore, a horse-shoed reserve bridle does not generate nearly enough force to pull your reserve bag out of its container. This is a good thing, because it prevents out of sequence deployments due to pilot chute hesitations. The basic problem with two reserve pilot chute systems like my Vortex (which I developed years before the Catapult, but did not market) or the Catapult itself, is that they cannot tell the difference between a pilot chute hesitation (very common) and a reserve horse shoe malfunction (very rare). So, the second pilot chute on these systems can easily pull the reserve free bag above a hesitating primary (spring loaded) pilot chute, allowing that pilot chute to get into the lines below the free bag, thus totaling your reserve. So, the Catapult system actually encourages out of sequence reserve deployments, which as I said above, is a very bad thing. I tried to solve this problem with the Vortex, but was unable to do so. The Catapult does not solve it either.

Most people who FLAT PACK my tandem canopies go 1,000's of jumps between partial malfunctions. The record is 7,500 between malfunctions at Skydive Las Vegas. Skydive Chicago, and certain military groups, reported similar results. Most DZ's who PRO PACK their tandems have 'functions every few hundred jumps. This differential between malfunction rates, Pro pack vs. flat pack, only seems to occur when packing large canopies.

Unless you have a lot of experience with internal, spring loaded pilot chutes (and therefore know how to "break the burble" at pull time to get them to deploy without hesitation), don't assume that pulling a reserve ripcord while falling "stable" at 1,000 feet at terminal velocity, is high enough. A pilot chute hesitation can easily eat up 500 feet or more. (We are all so spoiled by hand deployed pilot chutes.) And remember, from the time you DECIDE to pull your reserve ripcord, to the time you ACTUALLY DO IT is at least 2 seconds (400 feet) if you have a metal handle, and at least 3 seconds (600 feet) if you have a "soft" reserve handle. 500 plus 600 adds up to 1,100 which ISN'T GOOD when you start at 1,000 feet.

There are two main reasons for long waiting times on rigs: 1. Almost everything is custom. Even cutaway and reserve handle are embroidered nowadays. Another for instance...when you add up just main riser options, i.e. length, color, ring size, webbing type, toggle type, dive loops...we have over 4,000 different types of main risers alone. I'd hate to think what that number would be if we added up all rig options for every part. The point here is that it is impossible to stock anything anymore, so your order cannot be assembled from ready made parts, like when you order a computer from Dell. 2. Demand is not constant. Orders seem to come all at once, or not at all. This means that we keep just the right amount of staff to keep our yearly (weekly) average number of rigs flowing. When times are "good" a large backlog develops, and rig orders sit around for weeks (or months) waiting to be cut. Once a rig is cut, it is out of here in about 10 days. When someone says they can get you a custom rig in two weeks, it simply means they don't have any orders. We can't just hire and fire people every time demand changes. It's simply too expensive, and not fair to the people anyway. And it takes weeks or months to train someone new to do the kind of work jumpers demand on their "new baby". I wish I could just go back there and turn a knob to speed up the rig making machine when a lot of orders come in, but I can't.

A single rear riser break is very rare. Risers usually break where they go around the large harness ring. It is obvious that since the "reinforcement" in type 17 risers is below the confluence, it does nothing to prevent this kind of damage. When this riser broke, it "released" a lot of energy, thus preventing much more serious injury of the jumper. Which is a good thing. The only way I know of to prevent "killer" opening shocks, is not to jump Spectra (Microline) or Vectran. They don't stretch at all, and therefore do nothing to help absorb the energy of a really hard opening. As long as we insist on jumping non-stretch lines, incidents like this are bound to happen. (Canopies with Dacron lines can still open hard, but much less shock is actually felt by the jumper.) If something has to break, it should be above the main riser attachment ring. That is a basic rule of parachute system design. It is possible to make risers that are so strong that they remain intact while the harness below them fails. This is really stupid, but it has been done...recently, in fact.

The failure rate on the reserve ripcords we test is very low. I'll take a look at our test reports for the last year, and get back to you on the numbers of failed tests. By the way, TSO standards require that your ripcord DESIGN pass the 300 lb./3 second test, but does not state that you have to test every ripcord. You could choose to, for instance, test only 10%. However, since even one bad ripcord can ruin your day, we do 100% testing. We have added the new 11 lb.,4x90 degree side load test on every ripcord, simply because I no longer trust currently manufactured ripcord pins. The amount of incoming material testing I have to do now is at least three times what is was in the past, because of the generally lower quality of received goods. We now even have to test every friction adapter for slippage. One batch will come in that doesn't slip until 1,200 lbs., yet the next batch, from the same company, might slip at 300. Kevar went to crap about 4 years ago, and I had to redesign the lower bridle on my drogues to be easily replaceable, because now the drogue envelope now outlasts the drogue bridle...exactly the opposite of a few years ago. And don't even mention Velcro...It is nowhere near as good as it once was. I could go on and on...but that's my problem, not yours. What you get, in the finished product, at least from us, is the best materials available.

Quote:[Great euphamism, but what is the curve as related to skydiving gear and how do you define the safest equipment? To my knowledge, the majority of skydiving incidents do not involve engineering or manufacturing defects in harness/container systems.] It's true. Most fatalities involve humans failing to perform properly, not gear failing to perform properly. However, the Skyhook, like the AAD, performs a "human function", not a "gear function"...ie. An AAD does not make a reserve open any better. It simply "pulls" the ripcord...a human function, when the human fails to do it in time. The Skyhook, more or less, does the same thing. It "pulls the ripcord" when you don't. (It also allows the reserve canopy to open faster and softer, but that's another discussion.) So both AAD's and Skyhooks "make the person better", not the gear better, and therefore save more lives than "safer gear" ever could. According to USPA, 25 jumpers, in the US, in the last ten years, failed to pull their reserve ripcord after a successful breakaway. That's 2.5 jumpers a year who might have been saved by an RSL. Remember, an AAD might not rearm and fire in time to give you an open reserve, when you breakaway below 1,000 feet. So don't think for a minute that an AAD makes an RSL redundant.

The Skyhook will be licensed. Just when I'm not sure. It has now been "public" for just over a year. So far, so good. But as you know, reserves don't get used very often, so it will take a little while longer to get all the data I want before I let the device out of my direct control. Look what people did to my three ring release system...soft housings and reversed risers, to name just two disastrorus "improvements", "innovated" by other manufacturers. I've got to make sure the same thing doesn't happen to the Skyhook, although I'm not sure exactly how. There are also technical problems with other rigs... ie. Racers, Javelins, and some other rigs don't have the reserve kicker flap that the Skyhook is mounted on in the Vector. They will either have to add the flap, or mount it somewhere else...either of which will require a lot of testing. To further complicate things, the "Skyhook" is actually three different sub-systems...the Vector RSL, the Collins' lanyard, and the Skyhook itself. Each of these sub-systems must be integrated into each different rig. Also, the Skyhook freebag bridle is a different length than "normal", and I'm not sure if other reserve pilot chute designs will affect Skyhook performance. ( A different pilot chute launch profile might affect reliability) We had to do a lot of "fine tuning" to get it to work reliably on Vector III's. (We haven't even tested it yet on Vector II's.) Now as to cost. The Skyhook adds just $175 to the price of a new Vector (it's "free" on all tandem and student rigs we make). A new freebag and pilot chute costs $195, and the Skyhook greatly improves the odds that you will not lose them after a cutaway. So, if a Skyhook saves you just one freebag in your life, it is actually free, and you can buy a case of beer (on me) with the extra $20! So, if you have a lot of malfunctions, it might actually COST me money to sell you a Skyhook.

I'll admit it. Standard reserve pins and ball swages have always scared me. There is virtually no way to tell if they are OK by just looking at them. That's why we test 100% on ripcords...300 lbs. for 3 seconds, applied from handle to pin. And after the recent cracked pins, we now also apply an 11 lb. side load, at 4, 90 degree angles, on every finished ripcord pin we sell.

Just think what might have happened if this jumper had a "soft" reserve handle. With a fogged visor he could not see his reserve handle. With gloves on he probably could not feel it. Is it reasonable to assume that someone spinning rapidly on their back (possibly in a "panic" situation) will be able to quickly pull a reserve handle that he can neither feel nor see? Are you still sure you don't want an RSL?

30 years ago, when I invented the 3-ring release, I used soft housings on the first few rigs. I went to the present metal housings almost immediately, because they simply worked a lot better. (The first few people who wanted hard housings had to steal a payphone to get them. Luckily, I soon found a lot more legal source.) Not only did hard housings yield softer pulls, they also allowed simultaneous release of both risers. The long curved soft housing has no stiffness, and will therefore compress in response to the cable pull, causing the right side 3-ring to release before the left. This transfers the entire load of the now rapidly spinning, half broken away canopy, to the left riser. The now higher force on the left riser closing loop transfers to the yellow cable, and friction in the now compressed soft housing goes up astronomically. If soft housings are wet or dirty, pull forces get even worse. These problems just get a lot worse if your main malfunction is spinning rapidly. Soft housings were never a technological advancement. They were a very dangerous step backwards, made in the name of "coolness", and they hurt a lot of people. To this day it amazes me that no manufacturer ever "recalled" the soft housing rigs they had made. They just quietly stopped making them.

Let's see...A Mister Bill dive without releasing? Sounds like a tandem to me.

No, I don't see any problem removing the "crystal ball" from Vector II's or Sigmas, if the forward facing loop handle is installed (and of course an AAD is installed), and all tandem instructors that use the system are briefed on the change.

The RSL system on Vectors is different from that on other container systems. It is designed NOT to damage your reserve ripcord cable. The velcro attaching the RSL lanyard to the top reserve flap is designed to allow the RSL pin to rotate when you pull the reserve handle so that the pin will not jam against the ripcord housing. On Vector 3's this tab is a double velcro sandwich that almost always allows this rotation to take place. As noted, even if the RSL pin doesn't rotate out of the reserve ripcord end piece, there is no negative effect on the reserve container opening. The snap shackle that connects the RSL lanyard to the right main riser is held together by a short pin, which is held in place by a small spring. If this pin is not fully seated, or if the spring is weak, then the shackle might release on opening shock. The stainless steel shackles we now use have stronger springs than the brass shackles we used to use. That's why we switched. They make the RSL connection more reliable. On RWS tandem rigs, there is a small plastic ball attached to the RSL to act as an "emergency" ripcord handle, in case the tandem master can't pull the "real" reserve handle, because of left arm injury or student interference. This "crystal ball" is held in place by a small velcro strip. If this strip comes undone, and you have a hard opening shock, and your snap shackle is not fully closed or has a weak spring, then the inertia generated by the crystal ball on opening might pull it open. This is probably what happened to you. When the crystal ball secondary reserve ripcord was developed, Vector tandems came with a pud reserve ripcord, which was difficult or impossible to pull with the opposite hand. However, for quite a while now we have been using a forward facing loop reserve handle, which CAN be pulled with either hand. For all these reasons (and others) I have decided to ask people to remove the crystal ball on Sigma tandems when they convert to the Skyhook, and all new Sigmas simply come without it. Since these changes have been made, we have received no reports of disconnecting RSLs. One question...what main and reserve canopies were you using, and how hard was your MAIN opeing shock?

Here are some facts: Well over 95% of the rigs Relative Workshop manufacturers have hand deploy, not pull-out pilot chutes. "Packing Kathy" tells me that almost all the total malfunctions reported to her rigging service are on pull-out systems. Relative Workshop riggers have made the same observation. BOC hand deploys, in Spandex pouches, are simply more reliable overall, and therefore dominate the market. Pull-outs can work well, too. You just have to be more careful, and know exactly what you are doing when you use them. Just understand that your chance of a total malfunction will be higher with a pull out.

There is nothing wrong with Type 17 (1") main risers with "mini-rings, for solo jumpers....as long as they are made correctly. Relative Workshop's web page gives you simple tests to tell whether or not yours are. The components of the release system, other than the actually rings, have a greater impact on cutaway forces than the rings themselves. For instance, a dirty cutaway cable, or soft housings, or too short a riser loop, or lack of riser housings in a line twist situation, can all make a much greater difference in cutaway forces than having large or small rings.

Do you realize that when Orville Wright made the first flight in 1903, he wasn't current? In fact, I have it on good authority that he even had a pilot's license.

Spinning the rings was never necessary. All you do when you spin the rings, is put salt from your hands on the hardware. By the way, each opening rotates the rings a little anyway. If you will look at cadmium plated middle rings with over 100 jumps on them, you will see a slight "compression" of the plating evenly all around the "back" side of the ring. Flexing the webbing was a good idea when we used 1 3/4" Type 12 webbing to attach the smallest ring on "large" 3-ring systems. (We've used 1" square weave for over 20 years now.) On mini-rings, flexing the webbing was never really necessary. We left it in the generic 3-ring instructions only because not all risers are made with the correct webbings, and it doesn't hurt anyway.

Improper (or not) stowing excess brake line on "Velcro-less" toggles was implicated in 3 fatalities last year, as well as many, many breakaways. It is a very important subject. It is inconceivable that a manufacturer would put out a toggle system without any provision for excess brake line stowage.

Bill Booth, are you out there? Yes, but I'm on a ski vacation with my kids. Equipment compatibility is a big subject, which I don't have time to go into right now. However, on reversed (Integrity) risers...The scariest stories I've heard about them happen in two canopy out situations. Often, the main risers are held back across the shoulders, preventing the unfortunate jumper from cutting the main away in a "personal downplane" situation. Reversed risers offer no advantages, have lower mechanical advantage, have no published construction or inspection specifications (so you can't tell if they are going to work in a high "G" situation), and can kill you in the above situation (and others). They should be replaced, and you should get very mad at anyone who sold them to you. The same is true for most "soft housing" 3-ring release systems. More later...

If this RSL ring setup isn't "an accident waiting to happen", I don't know what is. A large number of people ARE going to pass the 3-ring closing loop through the RSL ring, simply because they can.

Absolutely! Suspension lines that are old (dirty and fuzzy) tend to stick together and knot more than new lines. That's why we recommend line replacement at 300 jumps. We learned this by the analysis of tens of thousands of tandem jump reports from the waiver period. Malfunction rates on canopies with over 300 jumps on a line set are nearly double those on canopies with line sets under 300 jumps.

The lowest tandem malfunction rate I've heard of, for an entire DZ, is one mal in 7,500 jumps at Las Vegas. They, of course, flat pack. Dz's that flat pack have consistently lower tandem malfunction rates than those who PROpack. I'm sure the reason is that line-overs are far easier to pack when you PROpack. When some DZ's have a tandem mal every few hundred jumps, and others every few thousand jumps (on identical equipment) the only reason has to be packing.