raymod2

From what I have read this one can log at 5Hz but it is $150: http://www.amazon.com/Qstarz-BT-Q1000eX-Professional-Vibration-waypoints/dp/B0036ANQ52/ref=sr_1_1?s=gateway&ie=UTF8&qid=1285275699&sr=8-1

Here you go, Mike. It's a 10Hz GPS for $80. It looks like it just came out this year. http://www.amazon.com/QSTARZ-BT-Q818XT-EXTREME-BLUETOOTH-A-GPS/dp/B003YCZINA/ref=sr_1_2?s=gateway&ie=UTF8&qid=1285269956&sr=8-2

This could be a useful tool for training purposes. Things like vertical speed, rollout height, gate speed, etc. could be compared on successive runs to determine what techniques produce the best results and where to focus your efforts at improvement. However, from your video it looks like the sample rate is around 1Hz which is probably a little too slow to provide meaningful data.

Very cool. Now all you need is to generate this data in real time and use it in an HUD.

That was an impressive landing in the video that fkaros posted. I am surprised he stood that one up. I doubt he could have pulled it off on a dirt or grass landing area, though.

LOL, it was a sloppy run. I made a sudden correction just after passing through the gates that visibly and audibly distorted the canopy for a moment. I hadn't considered that it might have had an effect later on during the transition. I also hadn't considered the effect of Cheesy Poof deprivation. I'll have to go to Target and restock my supply.

Here's a video from a practice run last weekend that shows the canopy pitching *forward* during a rear riser to toggle transition. I'm not sure if it indicates I transitioned too soon or too late but I thought it was interesting because it challenges the conventional wisdom that toggle input only generates lift because it pitches the canopy backwards. http://www.youtube.com/watch?v=B2MvjZCdVnQ

I don't think it was so much over your head as it didn't make any sense. 1) Your speed (gate speed) in a distance run is not a function of trim angle. It is a function of weight, parasitic drag, and (of course) technique. 2) Best glide ratio is not affected by weight nor is it particularly relevant in a distance swoop which is predominately horizontal flight with continuous changes to angle of attack. 3) I believe cruising heights of airliners are subject to several considerations including stall speed, the speed of sound, and engine efficiency. I don't see the relevance to swooping. 4) The Reynolds Number predicts the likelihood of turbulent (versus laminar) airflow. I figure the Reynolds Number for a parachute never exceeds 6,000,000 (assuming a chord length of 6.5 feet and a maximum speed of 100mph). But what does this have to do with wing loading?

Also, I have noticed that there are two different inner diameters for pool noodles. I've used the smaller inner diameter ones in the past. They are a pain to work them on the PVC pipe but they stay put once you get them on. They are a seasonal item at Walmart so you might be forced to go to a pool store depending on the time of year.

I'll bite. At my last comp at sea level I was using an initiation altitude of 1100 feet (+/- 100 feet) for a 450 degree turn on a JVX 90 (zero-p) with RDS loaded at 2.35. Notice I say "initiation altitude" instead of "turn altitude" - that's because some people initiate their dive by easing off the brakes and/or using double front risers. A decent amount of speed can be attained before you start turning. Yes, there are a lot of variables and even with the same set of variables there is a good range of initiation altitudes you can use. We experiment and try to use what works best. In my experience, all other things being equal, using a higher initiation altitude allows you to build more speed but makes it harder to put all your power through the gates.

@crazydiver: you are aware that RDS stands for "removable deployment system"? It is not the same as "removable slider". The primary benefit to an RDS is that it allows you to remove the pilot chute and D-bag from the top of the canopy.

Put a non-collapsible pilot chute on your canopy and try to swoop with it. It will be very obvious that it is fighting you during your dive and you will have a tendency to roll out earlier than you wanted or expected. In fact, you will probably feel that it royally screwed up your swoop. It is more than just parasitic drag. It is actually pulling on the top of your canopy, distorting it and frustrating your attempts to configure a low angle of attack. The same thing occurs with a collapsible pilot chute but to a lesser degree and it doesn't become noticeable until you start generating high speeds during your dive.

Sangi, you've made your point. The top pilots are sponsored. They are not free to change their canopies unless they want to give up their sponsorship or seek out a new one. For this reason competition results are not necessarily a useful metric for judging the best canopy design. So which is the better design? The JVX or the Velocity? First of all, you are not going to get an unbiased answer from a sponsored pilot (at least not on the record). Also, brand loyalty is like religion. It is very hard to engage people in logical discussions about it. I have flown (and competed) under both and I am not sponsored. I currently choose to fly the JVX because I still believe that a 9-cell has more performance potential than a 7-cell. But my opinion could change. I have not flown the competition Velocity yet.

As a competitor I agree with what Kolla has suggested. Adaptation is fundamental to competitive swooping. Changes in temperature, humidity, elevation, body weight, wind speed, wind direction, etc. must all be accounted for. I don't think that putting restrictions on elevation is necessary or desirable. I also agree with most of what CJ has said. I started swooping competitively right around the time they built the pond in Longmont, CO. I personally looked forward to competing there every year partly because of the pond but also because of the high altitude. You flew faster and farther and it was *easier* to hit the gates, at least for me. Sure you had to adjust your initiation altitude and, more importantly, you had to start your rollout higher. But anyone who has downsized their canopy or added lead or (gasp) switched from a 9-cell to a 7-cell has made the same adjustments before. As for the cost of jump tickets... $33? Really? I thought $25 was excessive in Australia. My understanding is that jump ticket prices are part of the bid and one of the criteria used in selecting the venue. I guess there weren't many bids this year.

Ian posted this news in a thread titled "Why Velocity is so popular?"... as if to offer it as proof that the Velocity is better than the JVX. Sangi was merely countering that implication. I don't think that makes him look like a fool.

Your comment sounds similar to one from "the lesson of the moth": i would rather have half the happiness and twice the longevity Let moths be moths is what I say.

I'd like to thank the jackass who started this ridiculous thread because I have truly enjoyed some of the responses. Especially you guys, hallux and Andy_Copland.

Better yet, never fly downwind of your initiation point.

I think the 10% estimate is a little bit of an exaggeration. I've seen people get 250 feet or so with an aggressive 90 degree turn but I haven't seen anyone get 2500 feet with a bigger turn. Limiting your turns to 90 degrees probably limits your potential somewhere in the ballpark of 50%. On the other hand, I do not understand why people have such a blase attitude about the ban on swooping at Lodi. It can no longer be argued that swooping is reckless and violates basic safety. It is a recognized discipline in the sport. A skydiving operation that bans swooping is not much different from an airport that bans skydiving.

I've always wondered why large planes are used for many of these swoop events. It seems incredibly inefficient to put 20 swoopers on an Otter, fly to 5000 feet, and then make 5 passes to drop them all. Why not use three 182's assembly line style? Al did this at this year's Last Big Splash and it appeared to work very smoothly. With 30 competitors the turnaround time between rounds was much faster than other events I have attended that used a large turbine aircraft.

Here is an updated report from AAD and a graph of the jump. According to the graph I reached a peak vertical speed of 40 m/s (89.5 mph) at 120 m (394 feet). It also shows that I exceeded the firing threshold for a little over 2 seconds and the unit took slightly less than 1 second to fire.

It doesn't really add up that the unit fired at 354 feet but the reserve didn't start coming out until 10 feet. I haven't heard a good explanation for that. I have asked Vigil to take back the AAD and reimburse me for it and for my reserve pack job. I am considering buying an Argus.

On June 14, 2009, during my 8th jump with a newly purchased Vigil 2, the unit activated and deployed my reserve while I was executing a high performance landing over the swoop pond at Mile-Hi Skydiving in Longmont, CO. I was dragged into the pond but I was unhurt. Equipment: JVX 90 zero-p (2.4 wing loading), PD160R, Skyworks Rigging RDS, Javelin J2, Vigil 2 Technique: right hand 450 degree turn initiated from 1200-1300 feet Here is the report from Vigil: The report states that the unit fired at 354 feet due to a vertical speed exceeding 78mph. Eyewitnesses reported the reserve deploying about 10 feet off the ground. My own observations were that the main started shuddering just as I was rolling out of the dive and preparing to put my toe in the water. Shortly after that my speed decreased very rapidly and I landed in the pond less than 1/4 way across (the pond is 350 feet long). The reserve freebag landed about 20 feet before the pond.

Have someone shoot video inline with the entry gate about 200 feet away. At that distance it won't make much difference if the camera is 5 feet AGL or 10 feet AGL. Assuming the gates are 40 feet apart and the swooper flies through the center then he will get an extra 6" before he verticals. No big deal since I doubt your gates will be exactly 10' high anyways.

I've watched Nick Batsch going horizontal as he passes through the entry gates with his face about 2 feet off the water.