JohnSherman

Clairification please: Parachute Recovery Systems Design Guide by Theo Kanacke is not numbered by page number just chapter number and chapter page. There is no page 340-341. I assume I have the wrong book. What is the title of the one to which you refer.

None! You are moving within an air mass which is called the wind if you are on the ground. It is only going to have an effect if you are not in the air mass and the air mass hits you. The relative wind you experience is from your movement within the air mass. Think about the boat in the water analogy

I guess we should do that for the cutters when they fire inside the reserve container. They both use the same power amd method. The only difference is that we just drive the ripcord cable and the cutter drives a cutter piston. Same amount of gas same amount of power. Same pyro and same airline consideration and if you need gloves to handle your cutter after it fires you will need them for this. If you don't you won't for this either. JS

I started jumping in 1958. I was in a car crash in 1965 which ripped a hole in my Atrium (where the Aorta attached to the heart) requiring 6 stitches. I was without heart beat for 6 minutes and technically dead. I had a resection rib which was broken in the crash. I didn't jump again until 1968 after I passed a First Class physical as I am also a pilot. I was 26 at the time of the accident and in good shape. If you can pass a 3rd class FAA physical I would think you would be good to go.

Yes, He and Scratch were the judges. That's Jeff Serales on the right. And Paul Schlee between Jeff and I. You can see the blond head of Hellen Tosher, Tyson, Frazer, etc peaking out from Garths shoulder.

Bruce was on the winning team at the firat Z-hills Turkey meet 1969. He is shown on the left. He is missed. [inline Awards_Cermoney_19690002.jpg] He was a pioneer in RW, a good one! JS

Don't I still make one for my tandem?

John, Your RSL system (or mis-rigging of it) has a built in error trap which played a role in these fatalities whether you will admit to it or not. ....Yes, I know read the manual! The reason that I brought this up is this. I think that the pin puller is the way to go provided there are no bent pins. It is a better way to go IMHO. But.....Ironically your system (with the RSL attached) has the highest probability of bent pins. More so that any other rig out there with the above scenario. MEL *** Believe it or not we did test it and as you say the caveat is in the manual. We tested it in the air as well as on the ground. While suspended under canopy, in the air, by the RSL x-connector locked under the top flap after a cutaway. The test jumper was able to pull the ripcord and the reserve deployed normally. There were no bent pins. We studied this on the ground before doing it. Strangely when the top flap is loaded there is no noticeable increase in force on the pin pull. I attribute this to the fact that the loop in tight from pin pressure in the packed position and the flap is loading the loop in a perpendicular direction while the flap itself is acting as a pulley reducing the load. Even the shock of the cutaway did not bend the puns. We knew, 30 years ago, that some dummy would make this mistake so we studied it and put it in the manual. We know of 2 occurrences of this error over that time period and that covers some 30,000 RSL equipped rigs.

It doesn't qualify. There was video of the hole thing, He never graspsed the ripcord handle. The pins might have been bent as a result of impact but they had nothing to do with the incident. The rigger admitted to misrigging the RSL under the top flap when he was changing the CYPRES batteries. The ripcord was pullable but wasn't pulled. The handle was not in the pocket but because the pocket had been modified by the user the handle came out and floated and could have been grabbed easly and the AAD didn't fire. Nothing to do with bent pins. Keep looking

This is a made up "What if". In the last 40 years nearly 100% of all rigs jumped had cloth loop and standard ripcord pins. To my knowledge there have been no fatalities attributed to the bent pins. Sure some have been found and I am sure some have been pulled bent. But no one has ever gone in from one. Cutters on the other hand, which represent only a small percentage of the overall population, have cause several fatilities and caused one company to close. If this isn't a "No Brainer" I don't know what is.

Ever try to push a rope. Its something like that.

The Advance doesn't use container friction retention to hold the bag until pilot chute loading, it uses a retainer with a pin release or so I understand it. This method while going back to Para-Flite time works. It was the method used before container retension. Container retention was something we developed in objection to the retainer and loop. Container retension was never intended to include "Friction". Current designer have gotten carried away with appearence and increased the friction to a dangerous level. The Basic folks have been aware of extraction problems and have none. Their videos, while not of good quality, do show deployment time approaching that of the Racer. At east they show deployment times and without the unreliable MARD. No body else does.

Kinda makes you wonder don't it?

How much is the pin bent? We have built a force generation tester which measures the pull force of the ripcord. Currently we have seen a low of 80 pounds and a high of 120 pounds. This is more than I can pull. I will post "Burn curves" in the future when we have finalized the Squib formula. We are at an operational state at this time but we want to hone the formula and tighten the spec. This process will take no more than 2 days when we get the necessary Pyrogin.

Let clear/muddy the water a bit.

May be where you live but not in the US. We have a perpitual maintaince program for all aircraft systems including parachutes. There is an peridoic inspection cycle on all components and during this inspection the unit is certified for service for the next cycle. When asked by the French government how long our parachutes were good for while they were stating that their parachutes were good for 20 years. Our answer was 120 days as that was the length of our cycle at that time. There is no life limit in the US even though some are still trying to get one set. I have rigs in service which were built in the early 70's,

In our thirst for test data information, I would remind all that Dave Singer, Chair of the PIA Tech Committee presented data, at the last meeting, showing comparitive results from the Raeford wind tunnel pilot chute test. I haven't seen the data as I don't believe a hand out was provided at the meeting and Dave hasen't responded to my request. Anyone out there who attended the meeting would be doing the sport a favor by sharing this data whether or it in written form or from memory. I know there were several pilot chutes tested and I am told that a Javlin and a Vector 2 were included. Additionally, money was allocated for further testing which might be going on currently.

A little heavy and a little low. LOL. Basically you might get away with no weight. I would add weight only for stability and to equalize between the test pilot chutes. The longer we can keep them in the air the better data. How's the dog and who won?

Interesting design, but WHY? What are they trying to accomplish? I understand trying something just because it is different but it should accomplish something better. If it ain't broke don't fix it. Change for the sake of change is dangerous. I would not like to speculate on any design without testing. Testing is paramount. Pilot chute testing is easy. Find a known good pilot chute and drop it from a good height along side the one in question. Make sure the total weight is equal. First one down looses. See the instructions earlier in this thread.

The AC further states that if a question of performance arrizes it must be resolved through testing. Performance must not be degraded. I certainly think it would not be advisable to put the world lowest dragging pilot chute in place of the worlds highest dragging pilot chute. This would certainly degrade performance. I can see it here on a form "Racer takes 4 seconds for a deployment after cutaway". However, it would not be for me to say and the substitution would reduce my liability.

Wow, it was a Wings you got! That’s a good thing. So it is apparent that you feel a little conflicted over what you have learned about their pilot chute. Here’s what lets do. Test the dam thing. You know how. Lets have a race. First one to the ground looses. I am posting the process here for other people to do the same. 1. Find an old Military surplus pilot chute. MA-1 type or any PC which has a traditional parachute canopy. Little Grabber, Vector 1, Racer, A3 etc. 2. Weigh it and your Wings PC. Add weight to each to stabilize them but make the total weight of each PC and store equal. Record the weight. 3. Find a tall place and drop them off together. First on down looses. 4. If you want quantitative results then measure the height of the drop suite and time the descent. 5. Divide the distance by the time to find Feet/Second. 6. Apply the Formula for Dynamic Pressure (Q = ½ Rho V^2) V is from line 5. 7. Find “Effective Sq. Ft.” by dividing the weight from 2 by the Q from 6. 8. Effective Sq. Ft. is the physical size times the Drag Coefficient. 9. If you know “Effective Sq. Ft. you can calculate the drag for any situation of speed and altitude. (D=Cd*So*Q). This low speed test is indicative of over all performance of any pilot chute, as we both know. I am not posting this here to give you instruction which you already know. I list them for the other guys who may want to do the same. I would love it if you would do the test and post it here, show photos and give data. I am sure you can find a place to drop it from out there like the Space Needle. The highest thing we have here in Florida is a life guard tower.

He is correct. But try to tell that to an Administrative Law Judge or a FSDO agent. We all know that AC's have the effect of law.

I don't agree with your assessment about the strength of the statement in the manual. I have written several owners manual for certificated gear in the past. In my original Harness and Container manual I made a statrment allowing both chest and back rated riggers be allowed to pack the SST piggy back. Piggy back were new at the time and most riggers had only a Chest ratting. There wes legal president for this statment. However the FAA called me and said their regulation take presidnts over the manual. PIA wanted me to challenge them but I removed the statement from the manual. This is a simular situation. The AC-105-2(x) allows the mixing of major components from different manufacturers. The manufacturer cannot prohibit that. For the manual to be definitive AC-105-2(x) would have to be recended.

Friction should not be counted upon to retain line stow bights. The mass of the bights and the location of the rubber bands determine the distribution of the mass of the stow. Ballance the mass and eliminate the asymetrical loading of the stows during deployment. This eliminates line dump.

Yeah Bill, and you guys say I never upgrade or improve. "bout time you got a new rig. Send it in and I will get you a Red one. I'll tell the story one more time as to why I went from Yellow (Nylon) coating to (Red/Orange) Teflon. RWS had just come out with the Yellow from the previously used clear coating. In their manual they said the Yellow cable was impregnated with Teflon and needed no oiling. The instructions went out to all manufacturers to stop oiling. We did. Turkey meet at the Hills and I had a new rig with 6 jumps and the yellow cable. I also had a PD 210 with Kevlar lines. Next jump all but 3 of the nose lines broke on opening and I found myself spinning in 2 different axis. Ripcord in one hand and pud in the other I pulled the pud first. No luck, I could feel the housing tighten around the back of my neck as I pulled. I dropped the reserve to try 2 hands, no better. I had a round Phantom 24 with a diaper so I pulled the reserve while still connected to the spinning main. The pilot chute went up toward the main and before it could reach it I grabbed the lines and jerked them so hard the diaper released and I then started pulling the lines in to keep the reserve out of the main. It inflated and jerked the lines out of my hands. I started to pull the main in and landed. I took the rig back to the packing area and tensioned it between 2 cars. No one could pull the 3 ring release cable. I released the tension and removed the cable. When I pulled it between my fingers it squeaked like clean hair. I lubricated it with oil from a dipstick and put it back into the rig and re-tensioned the rig. The cable pulled and released the risers with little effort. That Teflon was a good idea so I set out to make it happen for real. That's the Red or now Orange coating you see on some rigs cutaway cable.