billbooth

AC 105-2C has been around for about 16 years now. The way I understand it, it provides suggestions, or "advice", and does not set forth new law. This same AC also allows manufacturers and riggers to determine "compatibility". I think this is a subject about which the FAA would prefer not to be asked...you might say a "leave well enough alone" situation. Remember, it took them 17 years to make up their mind about tandem.

Here's a "catch 22" for you. I asked for the drop tower test to be added to TSO-C-23E to take care of the above "incompatibility problem" with "C" and "D". Trouble is, "E" is not yet issued, so no one can "legally" test (or label) to it. When we became aware of the new AC 105, we immediately drop tower tested some of our rigs to see what they could take. As Mike said above, the answer was well over 8,000 lbs. (Our tandem systems went to over 14,500 lbs. before failure.) But again, I'm TSO'ed in "B", and no strength labeling is required, or perhaps even "legal". I'm on vacation, and don't have a copy of the Advisory Circular with me. Does is say exactly how the strength of the harness has to be measured?

The original Para Planes had upper surface ring-and-ropes. To say the least, they were not very efficient. My first 300 or so ram air jumps were 3 second delays. When I started taking it to terminal, I got knocked out a lot. The canopy sure was pretty with all those brightly colored stars dancing around. After one opening in '72, I woke up in an ambulance. Oh well, everyone gets to be young and foolish at least once.

I never liked the "standard" single-sided RSL because if the RSL side riser releases prematurely for any reason, the reserve will be deployed into the still partially connected main, which has killed people in the past. The Collins' Lanyard (part of the Skyhook RSL system) cured that. Beyond that, I always pull very high, and figured I had plenty of time to get my act together after a breakaway. Rightly, or wrongly, I do worry about stability before I deploy my last chute. The Skyhook doesn't allow time for instability after a breakaway, even from a bad spinner. It also deploys your reserve in a direct line to the "vertical" axis of your body (where your main just was), guaranteeing equal line length at line stretch. By comparison, a pilot chute deploys your reserve into the relative wind, which may or may not be the "right" direction depending of body position. (When you're "sliding" sideways after a spinning malfunction breakaway, the reserve deploys "across" your body plane, resulting in apparent differential line lengths which makes for "sloppy" openings.) Also, RSL deployed pilot chutes lift the bag off very "slowly" at low speeds, giving the bag a chance to spin, resulting in a better chance of line twists. The Skyhook always pulls with the same force, in the same direction, regardless of your malfunction, yielding amazingly consistent openings. Simply put, after watching literally hundreds of video reserve deployments over the years, the Skyhook deployments simply look "cleaner" than the non-Skyhook deployments, and that makes me feel better.

You CAN order a Micron with an RSL and Collins' Lanyard WITHOUT a Skyhook (we do make custom gear after all)...but why would you. If you have committed to an RSL, then adding the Skyhook should be a no-brainer. Just a few years ago, most experienced jumpers wouldn't be caught dead WITH an AAD (even though many were caught dead WITHOUT one). Then came the CYPRES, the first really good AAD, and most experience jumpers now wouldn't jump without an AAD. I think the Skyhook will do the same thing for RSL's. (At last count, fully 70% of our new orders for sport gear include the Skyhook option.) I, except when I was doing tandem, never wanted an RSL until I developed the Skyhook. It simply removed every objection I had ever had against RSL's. Now, I simply won't jump without both an AAD and a Skyhook. When things go wrong in skydiving, they often go very wrong, very quickly. I simply want every "edge" available to me. I have lost too many friends who thought they were invincible.

I've been asked to comment on this discussion. For me, it is a sore subject. For the first 25 years I was in business, we all used cadmium plated hardware from US Forgecraft, with almost never a problem. Then Forgecraft went out of business, and now the problems seem never ending. The quality of the hardware and the plating have been "all over the place" for the last 5 years. For a while we were rejecting more hardware than we were accepting. We tried nickel plating a few years ago, because we heard that cadmium would soon be "banned", because it is a toxic heavy metal, with terrible manufacturing waste products. (I believe this has now actually happened in Europe) Sometimes it worked well, and sometimes it didn't. There is no danger of this hardware "failing", but chipping of the plating, especially on the harness 3 ring has been a problem. Cadmium plating also wears off, but it usually takes longer. We have concluded that our best course is to make the transition to all stainless hardware, which has mostly occurred in the sport market. Stainless 3-rings work great. However, the standard designs for friction adapters did not "translate" well to stainless, and slippage has become a problem. Even attempts to use "hang glider inspired" hardware designs has not been entirely successful, especially in the western US, where there seems to be something in the sand that makes stainless slip when the webbing get dirty. We are currently working on refining these designs. As a matter of fact, I just tested some prototypes yesterday. Both the cost and the "frustration" factor has been tremendous, but I believe we are making progress, and I believe that things will be back to "normal" soon, with the added bonus of all that bright and shiny stainless steel gracing our gear.

Years ago, I ran across a patent for a slider for round parachutes granted in the 30's. The slider for the ram air canopy was, more or less, re-invented in the 70's. Since I discovered this, I've looked through every old parachute patent I have been able to find, hoping for other "lost" gems. Nothing so far, unfortunately. Actually, I can't believe that all those hard openings on the early ram airs without sliders, didn't "beat" the idea into me.

Go ahead and play with your stainless steel riser rings if you must (I do). It won't do any good, but the oil or sweat on your hands won't hurt stainless. By the way, riser rings, when loaded toward failure, "potato chip", they do not "oval". In every case I've seen (with type 17, 1" risers), the riser webbing fails before the rings are damaged. The harness ring, which you can't rotate, is the only ring that will oval. We did have a problem with large (RW-1) harness rings which the manufacturer fail to heat treat, but that was back in 1981.

Tandem rigs don't COST...they EARN.

I originally designed the Skyhook for tandem and student rigs only. But, as soon as the test jumpers had a few Skyhook cutaways, they all wanted it on their own rigs. Reserves just seem to open cleaner, not just faster and softer, when Skyhook deployed. If you get a chance, try one, and you'll see what I mean.

35 years of experience...and watching literally hundreds of deployment videos, with every type and size of pilot chute imaginable.

I concur. In almost all cases, 27 - 28" pilot chutes are about as small as you should go. The only exceptions would be for very small canopies, or higher than normal opening velocities.

As I have said many times before: At terminal velocity, a "proper" pilot chute will get your main to line stretch in 0.6 seconds from pilot chute release...period. Anything much faster, or slower, will cause problems. Two second "hesitations" are totally unacceptable.

Tandem canopies are public transportation. Little old ladies and parapelgics jump tandem. Dacron lines give lower opening shocks. It's that simple. This might not matter much on a "normal" opening, but if someone make a small mistake packing which results in a super fast opening, the Dacron lines could save somebody's grandmothers life. I know Dacron is bulkier, but I've seen no evidence that Dacron lined canopies have more malfunctions. In fact, I believe the opposite may be true.

A little history might be interesting...In the early 70's both a Para Commander and a conventional container system cost $225 each. When Para Flite came out with the first commercial ram air, the Para Plane, they doubled the PC price ($550). I guess because they figured a ram-air was at least twice as good as a round. When John Sherman and I came out with the first "modern" piggybacks, we made a terrible mistake, we priced them the same as the conventional gear they replaced ($250), and we have been regretting it ever since. And back then, the canopies even came with risers and toggles. Guess who has to supply them now. The truth is that a modern piggyback costs as much, or even more to make than a cross braced canopy. Simply put, the only real money container manufacturers have been making is when we sell a canopy. (Witness that Performance Designs is larger than all the container manufacturers combined.) This "problem" has recently gotten worse by how extremely custom rigs have become. They are beginning to resemble NASCAR. Every rig is embroidered...many all over. There are at least 3 reserve ripcords to chose from, and even one of them can be embroidered. The same is true for cutaway handles and main pilot chute handles, not to mention several types of main pilot chute. It's very rare that we get to make even two rigs alike. We can no longer stock anything. We recently added up all the main risers options we offer...three types of 3-rings...3 types of webbing...6 or 7 different lengths of each of those types of webbing...each available in 10 or 12 colors...and lets not forget dive loops or blocks and riser housings. Multiply all these options together, and you will find out that we offer over 5,000 different risers alone. To be able to make all these custom options we have to stock literally thousands of separate inventory items. And because we don't use much of any particular material, we pay top dollar for the small quantity orders. If you want to have some fun, call up my good friends at PD and order a truly custom canopy. In addition to your normal fabric color scheme, tell them that you want the "A" lines red, the "B" lines blue, the "C" lines lavender, and the "D" lines pink. You also want every other reinforcing tape green and the line attachment tabs black. Oh, and by the way, could you please sew the whole thing together with orange thread. And don't forget your name embroidered on the stabilizers, in baby blue. If you can get them to stop laughing long enough, tell them you would like your new canopy for 30% off the normal price. And please don't tell me this example is far fetched...You do it to me every day.

The main reason I didn't like that one sided cutaway setup, was that if the RSL accidentally disconnected (a fairly common experience), you basically have no way to release the other riser. Besides, it does infringe on the Collins' Lanyard patent, which does the same thing if the right (RSL) riser accidentally goes first, but retains the ability to release both risers with the breakaway handle. This is just one of many devices I have tried in the past, but never gone to market with, because the minuses outnumber the pluses.

If you talk to the canopy manufacturers, they would probably tell you that all canopies fly better with a collapsible pilot chute. However, with a wing loading of about 1:1 or less, the difference in performance is very little. Years ago, I jumped the same canopy (1:1 wing loading) with and without a collapsible, and measured forward speed. There was absolutely no difference. What I could not measure was the effect an inflated pilot chute has on a "swoop". It tends to distort the canopy at high speeds. The higher the speed, the more the distortion. So, if you jump around 1:1, and aren't into "swooping", a non-collapsing pilot chute is just fine. I jump a 190 silhouette with a non-collapser, and I see and feel no distortion. The malfunction that scares me the most is a collapsed pilot chute that has opened the container, but does not have enough drag to pull out the main. The very slight advantage a collapsible would give me is simply not worth the chance that it might also give me this dreaded malfunction.

Some people will do anything to save a buck.

You guys should try an old Para-Plane at terminal with NO slider. I always saw stars, and was knocked unconscious quite a few times. I once woke up in an ambulance. I can't believe that the idea of the slider wasn't beaten into me.

The best automatic high "G" cutaway system is the human brain. Try using it to avoid the situation in the first place.

The yellow cable is "Lolon F" from Loos and Company. It is a plastic "alloy" specifically designed for tenacity, chemical resistance, low surface friction, and good temperature stability. It will go around a pulley at 60 below zero, and still remain functional. We have been using it for 25 years, and I have never seen it crack, come off the steel cable, or be "eaten up" by any lubricant people have put on it. (And I'm sure they've tried about everything by now.) As I have said before, we recommend a silicone lubricant. Ace hardware store in the US has a good one. A proper silicone lubricant is also good to 50 - 60 below zero. Just because your lubricant works at room temperature, doesn't necessarily mean it will work below freezing. It can get very cold up there guys, and most oils get tacky at low temperatures. Water also gets 'very tacky" when it freezes, so be sure never to jump a wet three ring system, especially the white closing loop. I have broken away while being dragged through the snow in high winds at the North Pole, with no problem using Ace silicone. (Exit temperature - 54 C., surface temperature -40 C.) My beard was frozen solid, but my 3-ring still worked! The red cable is Teflon. It is very slippery, but not very tough. (You can even damage it with your fingernail.) I have seen it crack and come off the end of the cable. If it were better than Lolon, I would use it.

Early tandem mains and reserves were often the same canopy, both TSO'ed...but that was nearly 20 years ago. I've heard of 360 canopies of that vintage being used as a main for a thousand jumps, or until they got scary (long openings, no flare) and then swapped out with that brand new 360 in the reserve container. Such conduct is atrocious, but not necessarily illegal, as long as a rigger keeps "recertifing" the reserve each time he packs it. These canopies were made by both Pioneer and PD, and back then there was no 20 use limit. If one of those ever got to my loft, we would, of course, refuse to pack it. But then, they would just probably get someone else. We always did everything the law allowed when these cases came up in the past. As I remember, we pulled a tandem rating or two. But with tandem now "legal" we have little authority any more...and no authority outside the US.

Of course, the best way to avoid a "non-cocked" pilot chute is not to use a collapsible pilot chute in the first place. But wait, that would force to jump a canopy with a sensible wing loading, which would make it a lot harder to kill yourself while trying to show off your new swoop technique to your friends...and what fun would that be. If you want to go fast by jumping a tiny canopy with micro lines and a collapsible pilot chute and slider, then you increase your risk of being hurt...pure and simple. High speed = high risk...whether it's cars, boats, parachutes, or women. Let me repeat myself: (Yes, I know I'm preaching) Jumping high performance gear increases your chance of dying. Please wait till you're ready, and get proper training. I, for one, am getting sick and tired of so many people getting hurt doing stupid things under "perfectly good" parachutes.

I wrote those words over 20 years ago for the original large 3-ring systems. Mini 3-ring risers have so little mechanical advantage that "webbing stiffness" is no longer a problem (unless you spill glue on the webbing or something). However, I will admit that webbing flexing does no harm on mini ring systems, and might actually do some good on large ring systems.

The only part of a correctly made Type 17 mini 3-ring riser (with 5/8" webbing holding the small riser ring) that might need flexing is the white closing loop. This "flexing the webbing" business comes from 20 years ago when we used 1 3/4" Type 12 webbing to hold the small riser ring on Type 8 risers. This webbing, because it was so wide in relation to the small ring, and because there is so much mechanical advantage in the "large" 3-ring system, could cause a problem if it got "stiff". Just clean and lube the yellow cable every month with silicone, and you should never have a problem.