diverds

For those who are interested, I am pasting an email string between myself and John LeBlanc of PD. He was very insightful on this issue. ----------------------------------------------------------------------------------------- -----Original Message----- From: Dave Schwartz [mailto:diverds01@yahoo.com] Sent: Wednesday, March 20, 2002 12:51 PM To: John LeBlanc Subject: Reserve/Main Sizes Mr. LeBlanc, I jump a Javiln container with an fx-116 and a swift plus 175. My exit weight is 250 lbs and I have just over 1700 jumps. I have been wanting to go to a bigger reserve in case I am ever injured or unconscious under it. I was told by some people at Relative Workshop that this would be a bad idea because of results from testing 2 squares out that are not close in size. Do you have any thoughts on this? I am not fond of the idea of jumping a reserve at higher wing loadings. I feel that there is just as good a chance of being injured or at least not 100 percent mentally there under a single reserve as there is of having 2 canopies out. I have landed my reserve off the airport and had no problems, but what about next time? Is there any thought going into this problem of mismatched canopies? In short, I want my fast main with a docile reserve. Is this possible? ===== Blue Skies, Dave S. ------------------------------------------------------------------------------------------ Dave, You've made a great case for being conservative in the choice of your reserve, but the choice of main isn't very congruent with this conservatism, is it? We have done extensive testing on the two canopies out situation, doing so on other brands of equipment as well as our own. A very sanitized report on this testing is available at www.performancedesigns.com. (I believe it is in the articles or seminars section.) I would prefer not sharing the gory details of the test jumps with you in detail, but let me say that the mismatched canopy combinations were pretty ugly. The smaller canopy does not stay very stable, and can buckle and distort into a totally unflyable shape. Basically, the bigger canopy eats the little canopy. We didn't test with cross braced canopies at the time, but I think they would be worse due to the smaller inlet shape and more critical airfoil characteristics. I am surprised that you are willing to jump such a small canopy as a main, but are so conservative on the reserve. There are several people who lean toward this direction, but making such a big jump in size such as this is unusual. Most bad spots occur when flying your main, since you fly it so often. It is true that your spot tends to get worse when you open lower on your reserve. Another thing to consider is that many people (including me) have a tough time flying accurately on a big canopy when current only on small ones. I'd just as soon take a familiar smaller canopy into a tight place than a bigger unfamiliar one. If you need the steep vertical sink to get in there, then I won't jump in that environment without leaving myself a big out to prevent that, or at least I'll pay a hell of a lot of attention to where I am at all times! Skydiving has its risks, and participants must decide which risks are acceptable and which are not. Obviously the huge risks of flying a FX116 are at a level you are willing to take responsibility for. The way I see it, when I am flying a really small canopy, I give myself so much room for error on the spot and opening altitude, that I'm willing to jump a small reserve. As for the durability of the reserve, I can't speak for other makes, but having participated in the development and testing of our reserves, I know that we've tested all of ours at 300 pounds or higher, at 180 knots or higher, and I know that the forces are actually lower on the 126 size I would choose than on the bigger ones. As for the unconsiousness issue, there have been several heavy people who have landed without injury under really small PD reserves, but again, its a bit of a crap shoot. On the other hand, no reserve will be big enough to allow survival if you fly downwind into the side of a building. Several years back an unconcious person flew through the side of a motorhome at Quincy, taking his head off. So we get back to the question, "What level of risk is acceptable?" In the end, the choice is yours, but it should be a well though out one that includes looking at as many risks as you can forsee, and then deciding which ones are worth assuming. This includes evaluating the risks of having two highly unmatched canopies out, and deciding if that risk is one you want to take over the other risks involved with the other options. I hesitate to recommend that anyone go smaller on their reserve, but in your case I think it is the second best option, right behind going to a bigger main. By the way many people who are flying our Velocities use a PD reserve one size larger, but no more. For example, a person flying a Velocity 111 might choose a PD-126 reserve, rather than a 113. (I have flown both the 113 and the 126 at your wingloading, and they land great in this range if your approach and flare is reasonable. You may want to go to the PD-143 size, but there is the risk that having two squares out is more likely to cause problems. We also make our PD reserves available as demos, so you can see how they fly, stepping down in size if you feel it is necessary. I hope this information helps you make a good choice. Sincerely, John LeBlanc Vice President -Dave "Gas...Undercarriage...Mixture...Prop...Beer"

Thanks for the info. -Dave "Gas...Undercarriage...Mixture...Prop...Beer"

Okay I read the forum. Looks to me like he only made a couple jumps. I believe the other tests were done by the Army and involved many more jumps. Not to say that Dereks test is not valid. I just think opinions should be formed after a little more experimenting then one or two jumps. -Dave "Gas...Undercarriage...Mixture...Prop...Beer"

Okay, I went to PD's site but could not find an email address for Mr. LeBlanc. Do you happen to have one? -Dave "Gas...Undercarriage...Mixture...Prop...Beer"

I had not done that but I will. Thanks. -Dave "Gas...Undercarriage...Mixture...Prop...Beer"

I jump a swift plus reserve at a wing loading of 1.42. This is an F-111 canopy and it has landed me well, but I had to fly it well if you know what I mean. I would like to go to a bigger reserve in case I am ever injured or unconcious under it. I feel a lower wing loading could help me under these conditions. However, after talking to some manufactures I was reluctantly convinced to stay with my current reserve. I was told that my reserve should be as close in size to my main as possible because of tests done with 2 canopies out. In these tests when the reserve was not close to the main in size, it caused much more radical results like downplanes and entangelments. When the reserve and the main were closer together in size it generally resulted in a biplane or side by side configuration. So I guess you need to decide which is more likely to happen, 2 canopies out or being in a situation where you are not 100 percent alert under your reserve. By the way, my main is an FX-116 and my reserve is a Swift Plus 175. My exit weight is 250 lbs and I have just over 1700 jumps. I would like to hear from people in the business who know what they are talking about. Chris? Dan? Mr. Booth? Mr. Galloway? Any thoughts? -Dave "Gas...Undercarriage...Mixture...Prop...Beer"

Looks like I spoke too soon. -Dave "Gas...Undercarriage...Mixture...Prop...Beer"

I like that you are planning on doing some jumps on a 150 first. When you do go to the 135 just fly it conservitivly(spelling?). Do some hop-n-pops at 10'000 and learn the canopy. Find the stall point. Practice several flares at altitude to get the feel. Do both toggle and riser turns to learn all aspects of the canopy. Then fly it straight in on landing (no speed building manuvers) for a couple hundred jumps until you are fully aquainted with it. Know your parachute! Oh, and have fun. -Dave "Gas...Undercarriage...Mixture...Prop...Beer"

I think it is pretty interesting that there have been 20 replies to this thread and I only see one that lists anything other than a Sony for video. Sony DV ROCKS! -Dave "Gas...Undercarriage...Mixture...Prop...Beer"

Sony rules. I use a TRV-30 in a D-box mounted on a bonehead Optik. Very clean setup and very light. Don't mess around with other cameras. Get a sony DV camera and all will be peachy. -Dave "Gas...Undercarriage...Mixture...Prop...Beer"

That is a good plan. As a tandem instructor I can say that I would be very leary of letting someone with limited experience in either skydiving or camera flying video any of my tandems. When you have a drouge above you, you are a sitting duck and you need to be able to completly trust the people flying with you. If a camera person gets too aggressive on a tandem there is not much the tandem instructor can do to avoid a collision or a funnel. Learn to fly yourself and your camera well before you ask to shoot tandems. -Dave "Gas...Undercarriage...Mixture...Prop...Beer"

Yes they suck too. -Dave "Gas...Undercarriage...Mixture...Prop...Beer"

About 1300 or so. -Dave "Gas...Undercarriage...Mixture...Prop...Beer"

Hmmm...glad you bestowed that title on him. I would have hated to see it go to someone like Norman Kent or Mike McGowan. Those guys really suck at shooting video. -Dave "Gas...Undercarriage...Mixture...Prop...Beer"

It could also be said that you don't really skydive or swoop period...depending on your definition of the two. Just kidding. Not really. No I am kidding. Haha...im dead serious. No joking...NOT. -Dave "Gas...Undercarriage...Mixture...Prop...Beer"

A friend of mine found something called an Evolution 2000. It is an audible made by the Cool and Groovy Fridge Company. In the add it says that it comes with software and an interface cable to download your jumps like a Pro-Track. Has anyone heard anything about this. If so how does it compare to the Pro-Track? What features does it have? Any feedback would be apprecieated. -Dave "Gas...Undercarriage...Mixture...Prop...Beer"

I disagree as well, I just bought a bonehead Optik with a D-box and it is very clean. -Dave "Gas...Undercarriage...Mixture...Prop...Beer"

What do you guys think of the new Bonehead Optik? -Dave "Gas...Undercarriage...Mixture...Prop...Beer"

Hmmm...what if I just wear the suit on tandems? -Dave "Gas...Undercarriage...Mixture...Prop...Beer"

I agree with the above posts. There is a time to say "lets not swoop today" and there is a time to say "lets not jump today". Not knowing when to do so can be hazerdous to your health. -Dave "Gas...Undercarriage...Mixture...Prop...Beer"

Just to keep things in perspective, you could say the same thing about skydiving in general, or skiing, or snowboarding, or skateboarding, or bike riding, or petting small furry animals. There is an element of risk in many activities we do, and if you do them long enough the chance of an injury increases. Do your best to be safe, listen to others input, and always be open to learn. -Dave "Gas...Undercarriage...Mixture...Prop...Beer"

Thanks...thats helpful info. -Dave "Gas...Undercarriage...Mixture...Prop...Beer"

OUCH! Thats like twice the cost of a reline with vectran. Is the new slider and the stable rib a requirement to go to hma or can you get the cost down if you just do the lines? -Dave "Gas...Undercarriage...Mixture...Prop...Beer"

Chris, How about letting us know what it costs. I have an fx116 that will be ready for reline in about 100 jumps. How much $$$ do I need to save? -Dave "Gas...Undercarriage...Mixture...Prop...Beer"

So once I have captured something to the computer I have already lost some quality? I thought the great thing about digital video was that you could go from the camera to the computer and back without loosing any quality. -Dave "Gas...Undercarriage...Mixture...Prop...Beer"