billbooth

It's Les Preludes.

I recently answered that one. Please check my posts for the last couple of weeks.

If an existing rig has no provision for an RSL in the first place, (riser ring, velcro bridle path) then the answer would be at least $200. To install a Skyhook from scratch you have to 1. Disassemble, and sew an RSL attachment ring to the right riser. 2. Sew an RSL bridle path over the right shoulder. 3. Shorten the reserve freebag bridle and sew a Skyhook to it. 4. Remove the single long 3-ring housing, and replace it with a split housing for the Collins' Lanyard. 5. Fabricate and install the Skyhook bridle attachment "pockets" and flap to the top reserve pilot chute kicker flap. 6. Fabricate the combination RSL, Collins' Lanyard, and Skyhook Lanyard. And 7. Put the "whole nine yards" together. Needless to say, this is much easier to do on a new rig while you are making it. As an option on a new Vector III, we charge $175. This is actually quite a deal when you consider that a lost reserve freebag and pilot chute cost $195 to replace, and the Skyhook greatly lowers the chance you will ever lose your freebag. But as I said above, all this is theoretical, because we have not tested the Skyhook on Vector II's and therefore do not offer a retrofit.

Sorry about not responding to e-mails at bill@relativeworkshop.com. That address is so polluted that it often gets 350 junk e-mails a day. I have installed a spam program. It helps some, but it also dumps good e-mails on occasion. My dropzone.com address is non-polluted (at least for the moment). In answer to your question. At the present time, we are not converting old Vector II's to Skyhook. The Skyhook has not been drop tested with Vector IIs, and we do not feel that there is a sufficient market in Vector II conversions the justify the cost. Besides, for the first few years of such a radical new system, I wanted to remove all possible variables, and putting the Skyhook on two different kinds of rigs is a hugh variable.

The theory is that no rig will bounce twice. There was a four way team in the 70's that all jumped "bounce rigs".

Whatever you said. I think I must have missed that chapter in high school math...percentage increase vs percentage decrease, or something like that. Anyway, you got the point.

Can I watch?

You would have to send me a picture of the RSL on your Vector. If it is a Relative Workshop RSL, with a semi-curved pin directly attached to the end of the RSL, it should have a "guide ring", through which the RSL passes (unless it has the Skyhook installed). If it is some other after market conversion, I'd have to look at it to know if it is safe. By the way, most after market conversions aren't legal.

Years ago, we mounted a High priced (1000 samples a second) digital scale on a the back of a harness, and connected it to a ripcord. From the standard reserve ripcord position, everyone could pull over 85 pounds with both hands...hell, one girl pulled over 100 pounds, and a few guys pulled over 150 pounds. "Soft" reserve handles generated forces nearly identical to metal handles. These numbers are from memory, but are probably pretty close. From other tests with the same scale, I have learned that if you pull "quickly", from a "running start" (slack in the cable), the pull force necessary to open the same reserve container is up to 300% lower than if you apply the force gradually to the handle. Most riggers only have a spring loaded fish scale, and therefore must apply pull forces gradually in order to read the scale. So, what reads 30 pounds on the fish scale in the loft, will only be around 10 pounds when you actually pull your reserve in an emergency, because I don't know of anyone who applies ripcord pull force "gradually" while falling rapidly toward the earth.

We have not tested a Skyhook from every conceivable main malfunction, as that would obviously be impossible. However. since the Skyhook gets the reserve out of the bag in about 1/2 a second, your main malfunction would have to be spinning YOU at 120 RPM to put a full (360 degree) line twist in your reserve in that time...and that's one-hell-of-a spin rate. Most breakaways from spinning canopies on Skyhook tests produce no line twists. The worst twist I have heard of is about 180 degrees (1/2 a twist), and that jumper said that it was gone in about a second. This question won't be answered definitively for many years, because reserve systems are used so infrequently. However, with one year of actual Skyhook use under our belts, I am optimistic that reserve line twists on Skyhook breakaways will not become an issue.

The "Skyhook" itself is a small metal fitting which is sewn to the reserve bridle. When you pull your reserve in response to a main container total, the Skyhook automatically disconnects itself from the Skyhook Landard. The Skyhook then leaves with the freebag bridle. All that is left of the system in your reserve container, is one end of the 6" long Skyhook Lanyard, which is connected to the RSL, which isn't going anywhere because you have a main total. The Collins' lanyard connection between the RSL and the left (non-RSL) riser's 3-ring release cable doesn't come into play at all in this scenario. PS. When I read this reply it seems overly complicated...It really isn't. All you have to know, is that the Skyhook system automatically handles every scenario I, or anyone else who has talked to me about it, has ever come up with. I'm sure nothing I make will ever be perfect, but after one year....so far so good.

If you still have "soft housings", please get rid of them.

We don't publish an exact length, because it depends on the bulk of the particular reserve being packed, and the skill of the rigger packing it. Even our riggers, who pack hundreds of rigs a year, sometimes have to resize loops during a packjob, because no two reserve canopies, even of the same type, have the same pack volume. Even temperature and humidity can affect pack volume.

We have dropped Vectors and Javelins (which are both constructed out of type 7 and 8 webbing) on PD's instrumented drop tower, and both harnesses BEGIN to come apart at around 8,500 lbs (applied dynamically). To a 200 lb. jumper, this represents over 42 "G's", which is about twice the force required to kill a human. So, I don't lose too much sleep over the issue.

Obviously, I don't make the Javelin, but I think I can safely say that the riser covers will be instantly opened by a pilot chute that pulls at least 50 lbs.at low speed, and over 100 lbs. at terminal, where you will be if you have a main total. Rigs are not designed to work on a table. They are designed to work while you are rapidly falling toward the earth. You hand deploy pilot chute won't open you main when you throw it on the ground either...will it?

Before you panic, go to www.virusmyth.com. What you find will probably make you mad, but it will also make you feel a lot better.

I have only measured F-111 pilot chute drag. There shouldl be little difference when the F-111 is new. However, F-111 does gain porosity as it ages.

Anyone skiing at Lake Tahoe (Squaw Valley), Feb 14-17, before the PIA meeting?

N/A

I was curious about the newly packed Vigil firing at the loft, right after cutter replacement, so I called Vigil in Belgium. They have inspected the suspect unit, and have found the cause. It seems that when the rigger closed the case after replacing the cutter, he inadvertently trapped a battery wire between the two havles of the case, crushing the insulation on that wire. The first time the rig was handled, the resultant short circuit fired the cutter.

"I've heard that a PC in terminal velocity pulls at about 160lbs force." A 36" pilot chute, at 120 mph, pulls at about 120 lbs. A 27" pilot chute, at 120 mph, pulls only at about 56 lbs., if it is properly made, and in still in "trim". So whether or not your pilot chute will pull your bag out of a tight container depends on the size and construction method of your pilot chute...plus how fast you are going when you pull. Remember, someday you may have to do a fairly low emergency exit.

The only way to make a small fortune in skydiving...is to start with a large one.

If no one should buy a new piece of equipment until it has been out for two years, then there would NEVER be any new equipment. We would all still be jumping rounds with Capewell canopy releases. No, wait a minute, we wouldn't be jumping at all, because even round canopies and Capewell releases were "new" once.

Look in the February issue of Skydiving...although I think it would be more appropriate to put the "ad" in the April First issue. It's the cleverest spoof I've seen in a long time. I especially like the antenna.

On Vectors, we recommend keeping the reserve pilot chute fabric out of, but folded closely around the spring, simply because the pilot chute jumps further when packed this way. Putting fabric between the coils of a spring is like stepping on your shoelace, seems to me.