JohnSherman

No, and the bad part is that you can't rely on it or predict it. It varies from way more drag than you need to not enough drag. You could have in situations such as twisted lines and a full canopy where you got more drag than you need, but there are videos of streamers on YouTube that, because you are vertical, you are falling faster than you would be if you were on you belly, no drag there. If your main pilot chute is collapsible, as it always is on Skyhook tandem, you will have no drag and you must go back to and rely on the reserve pilot chute which has only 2.3 Effective Sq. Ft. At the point in the deployment where you are quoting 18 pounds (1 second after release from a 20FPS descending main at 2000 ft. on that model of pilot chute only) there is only 3 pound per sq. ft. resistive pressure available. With 2.3 Effective Square feet on the Skyhook reserve pilot chute you will have only 6.9 pounds of drag not 18. That’s why some rigs have a Skyhook. It takes more than 6.9 pounds of drag to pull a tightly packed bag out of the reserve container especially if the reserve weighs more than 7 pounds. The point is; that the Skyhook is sometimes faster and sometimes slower than a Racer with an RSL. The Racer will be predictable and consistent and the Skyhook will vary depending on the severity of the malfunction. BTW: That 18 pound number you have latched on to is the maximinum allowable extraction force of the reserve bag on any rig. Most pilot chutes will just barely pull it and some won't at all. They are the ones who need a Skyhook.

Not since the 1940's when they first formulated Nylon. Most manufacturers I know only make service life claims which limit service life. Sell more gear that way. This is a small market you know. However, if you look at even partially maintained gear made in the 1940 it is servicable. The formal service life of most gear is 180 days or the duration of the inspection (repack) cycle.

When RSL were first introduced it was done by Perry Stevens for conventional gear with a chest reserve. It was called a “Stevens System”. The main risers had dual (one on the front and one on the rear) cross connectors at the junction of the lines to the risers. Note: Cross connectors were required on any jump made by US Navy personnel, if a cutaway was planned. The right main riser had attached to its base a lanyard which had to be hooked up on every jump to the chest reserve ripcord as that was the ripcord pull connection. This configuration was almost guaranteed to knock some teeth out when used. That reserve ripcord handle, which usually had and AAD firing mechanism on it was heavy and if it hit you on the way by it hurt. Piggy backs came out and the Stevens system was adapted cross connectors and all. A couple of early ones had the dual cross connectors but they would catch on the bottom of the reserve pack and hang up. The Navy had one hang up after a cutaway and it jammed the reserve so that only the PC came out. He landed hanging by the cross connectors of the malfunctioned main. Broke his wrist. Its all on video. Happened at El Centro in the 60’s. Well cross connectors were no good at the end of the risers on a piggy back so most of the manufacturers just did away with them. Except the Racer, where they kept the original concept by moving the cross connector to the base of the risers, where it also acts as pull lanyard. Other manufacturers have developed other methods, for a complete explanation see:http://www.jumpshack.com/default.asp?CategoryID=TECH&PageID=RSL&SortBy=DATE_D and follow the links to more information. Then you will be equiped to make a decission.

Peter Draper had posted the entire Racer Packing DVD on You Tube. It is in 5 sections. All 5 may be found at: https://www.youtube.com/user/ParachuteLabs?feature=mhee Thank you Peter

The British brought that up some 40 years ago. We tried to fail it with a packing paddle trying to push fabric into the tightened loop. No way. We could not make it happen. Pure speculation can only be absolved by having over 40,000 rig in the field over some 40 years and never have it to happen. The test of time would have failed it if it were to fail.

It does. I downloaded the video and brought it into my Video Editor which has been down for over a week. Your first capture “Bag lock chop” is a long time after Riser Release. The risers are halfway up the fully extended reserve bridle. On my time line it occurs at 1:01.05 I used a different time line but they are all relative. I get: Chop @ 1:00.10 Your Bag Lock Chop picture @1:01.5 Reserve bag out of container@ 1:01.09 Reserve landable/slider down @ 1:08.08 Remember that 13 foot bridle with a PC on one end and a bag on the other is about 16 feet or the distance of separation in the first second. That is commensurate with my observation. From Chop to Landable I get 7 seconds and 23 frames @ 25 FPS that’s 7.92 seconds. I don’t believe you can give the Skyhook much credit for this one. Incidentally; This is a great video to show how a tandem pair go onto their back when a bag lock occurs. Vasilli was correct.

I don't know but I have a digital recording anamometer with altimeter which record against a time line and I have a Firebolt 146. If you know someone with the correct weight and available time and ability I'll make it available and pay for the jump. I do have data on some size weight combos and am attaching the data from a 200 loaded at 1.05 to 1. I would expect from the information found in this data that a 146 would perform about the same. This seems to be in the neighborhood of 15 to 20 FPS or 10 to 13 MPH.

The clocks aren’t off, you are correct and I have learned a bunch and proven a theory. Both cutaways were from fully deployed mains. That hurts the RSL and helps the Skyhook. Reason: The RSL is always the same; it is consistent because it always uses the pilot chute which will always have the same drag capabilities. The Skyhook is faster when it has the very high drag of a fully inflated canopy but it will slow down depending upon the drag of the malfunctioned main. As the drag of the main (which is working as a pilot chute) decreases due to an increased severity of a malfunction on the main, the rapidity of the deployment also decreases. My previous views and timings were of higher speed mals to the extent where the malfunctioned main had no drag and the main pilot chute was doing all of the work. This can be dangerous if the main PC is collapsible and has collapsed. In a bag lock the collapsible PC doesn’t collapse with the bag closed. This is where Tandem gets tricky. The drogue has already collapsed upon release and is not available to assist the main if it has deficient drag. So now we are back to depending on the reserve pilot chute which if any good we wouldn’t need the Skyhook.

Yeah, but not even close to “as quick”. The Racer Tandem does it in 4 seconds, the one on the video above takes almost 6 seconds. Hard to tell exactly when the canopy is landable. Win to the Racer by a bunch. Racer Tandem deployment: https://www.youtube.com/watch?v=FtNKXDW0Ixo&list=HL1355429170&feature=mh_lolz This certainly substantiates my assertion the Skyhook is not necessarily faster. In some cases (Tandem) it is still slower than the Racer. Get out you stop watches folks or one of you video types could match them side by side.

Correct, it actually depends on the capability of your pilot chute. A good pilot chute will stand you up, right now. Free bag hang up is not really the issue here. It is whether or not the reserve pilot chute has the necessary drag to extract the bag. Some manufacturers use pack compression as a staging method (We don't). Pack compression can lead to high extraction forces as we have seen. Does the pilot chute have the capability to overcome those forces? Ask you manufacturer; make him give you numbers and test results. Make him give you a max extraction force so your rigger can make sure the bag will come out within the capability of the pilot chute. Look for “Effective Sq. Ft.” marked on the pilot chute. You can take that number times the Dynamic pressure for that speed and altitude ( See:http://www.jumpshack.com/Q.htm ) and calculate to and find the drag. And for god sake if all you have to compare equipment on is comfort, looks, and options don’t admit it by declaration. There are too many functional issues which could be asked about.

It has not, here is another one: http://www.youtube.com/watch?v=QtgneR9Ei00

I have been nit picked on this as to which one is quicker. They are close, no question The Racer without a Skyhook and a Vector with one. You judge the risk and cost value. Now lets look at the big canopies with the more demanding deployments, like tandem. Try as I may I haven't seen a good tandem video with a Skyhook to compare with this actual field video. See: https://www.youtube.com/watch?v=FtNKXDW0Ixo The tandem deploys the reserve in 4 seconds after a cutaway from a 500 sq. Ft. canopy with a broken line. Very low deployment speed. You can hear the pair talking. Show me a Tandem Skyhook video which is as fast.

Peter, A couple of things: At 2000 ft I calculate 52FPS or 35.5MPH which generates 3 psf. The standard Racer Reserve PC is 36 inches diameter or 7.06 Sq. Ft. (The SRP is 30 inches) With a Cd of .83 we calculate 3*7.06*.83= 17.57 pounds Rounded off to 18 pounds. We agree on the numbers but you just got one of my small ones (SRP) which is not used on anything but smaller canopies. A Racer free bag will not take 18 pounds to extract. I provided that number as an absolute ceiling for any rig because I don’t know of any pilot chutes which will handle it. It must be the absolute acceptable maximum for any rig when we test it on the ground. We do limit our extraction at 17 pounds but we know it is just the weight of the canopy and bag that is required and I put the big number out there because I knew our PC could handle it even on tandem reserves. I can envision this event happening if the reserve fired just as the main blossomed. The PC takes 1 second to get to the end of the bridle at 3 Pounds per Sq. Ft. (Q). But now the canopy doesn’t fly at 35MPH. It maybe flies at 15 to 20 MPH. At 23 MPH at 2000 ft. the Q is only 1.28 pound per sq. ft. 5.86 Effective Sq. Ft. There is only 7.5 pounds of drag. Not enough to pull the bag out horizontally when aligned vertically. It comes out only when it is supposed to. I like that. I will find out more tomorrow. John

Yeah, now I have to go and modify all thoes Racers so they will hold the bag in at that angle. I'll never learn. Oh BTW: Here is another one:http://www.youtube.com/watch?v=QtgneR9Ei00

Parachute Labs., dba Jump Shack is conducting a Rigging course in Deland, Fl. from January 12 thru 18, 2013. This course is for both Senior and Master canadates. Instruction will be from the folks at the factory. FMY: Contact Info@Jumpshack.com or call 386-734-5867. DPRE on staff for finals in house. Only 3 slots left.

Usually, when I have a partial, the malfunctioned main sets me up into the vertical. I know that it would be wrong for me to go back into the horizontal because I want the air flowing over my back to sweep off any possibility of a burble. Additionally, I am in a position to accept opening shock. Likewise when I am deploying from the horizontal (main or reserve) I "Sit up and dump" or get vertical for the above reasons. The biggest problem I have with test jumpers is that they want to go back to the horizontal after release. That’s dead wrong, fly on you shins, stay vertical. You will get a faster smoother opening. Oh! I have been designing rigs for 40 years and didn't know that.

It was a V3 with a PD176R packed on 3/20/2001 and as said a 170 main. It was not staged. Remember the fact that the main was full and packed, this might make a difference. I don't know what is supposed to go in there as it came to us packed for cyclic inspection and we videoed it as we often routinly did. I believe the combinations were correct. This happened in 2001 and has been on the web for that long. It is not uncommon. Yes the owner was told and shown the video. I don't believe he is in the sport any longer. A USPA Bullitin issued a couple of years ago solicited info about situations like this to be reported to the PIA tech comm. There has been considerable conversation over the years on this forum. If you want to know about more, just ask for it. I am sure you will get your inbox filled.

Yes, I do. What would you like to know?

Buy the big one and enjoy the longer glide and softer landings during your lean seasson. If you are told that you are underloading the canopy in the lean phase find a different canopy.

Does it come with a sign readable from 25 feet which is to be mounted on the rig anouncing to your fellow skydivers that you have an AAD set to fire at xxxx altitude? If a CYPRES set to fire at 750 will fire at 1000 feet in a track what will a CYPRES set to fire at 1500 feet fire at in a track? 2000 feet?

I think he is refering to an improperly seated pilot chute which tips to one side. If so we have miniminized this by hand sewing the Reserve Closing (Quick Loop) loop to the pilot chute at the factory. The loop must be centered exactly from 12 o'clock to 6 o'clock or the spring will not seat properly. When this is done in the field we recommend the rigger make a template to mark the proper positions on the pilot chute and adhear to those locations when tacking the Quick Loop. If you get the loop off center by to much the spring will tip. Ugly!

I wouldn't usually jump in here but now that you asked... Stronger Harness, Faster reserve, more reliable deployment system (SPEED Bag) Known/published reserve extraction force and reserve pilot chute drag capability. Ask the other guys for that spec and see what you get. Guaranteed left/right riser separation within 2 inches on cutaways. Teflon 3 ring release cable, no oiling required for easy pulls at high loads.

An old subject. I am linking to our position on "Head Down" Tandem published back in 1998. http://www.jumpshack.com/default.asp?CategoryID=TANDEM&PageID=TANDHEADDOWN&SortBy=TITLE_A Racer Tandem harnesses will withstand a terminal drogue deployment.

Read the reviews at:http://www.dropzone.com/gear/Detailed/88.html Note the dates. The second review is for the current version.

Not this manufacturer. This is maddness. Try this on for size. You are on a big way everybody has a CYPRES and each person has set their own altitude. Some could be as high as 1500 feet. The unit raises the firing altitude 100 feet for each advance, up to 1500 feet. I don't want to be there. I predicted this was going to happen. We did a poll about a year ago. The response was in favor of the rig manufacturers fixing their problem. They don't know how. This won't solve the problem. It will delay root cause definition for a few more years as the manufacturers who make rigs which will not deploy in 300 feet continue to sell defective products. If the pilot chute won't pull the bag out more altitude will not help.