markbaur

Bump. Can I vent here? If it's not condolences, it's congratulations. I don't learn much from one-liners like "Sweet job, man!" or the longer versions, and I find I am less likely to check for good information if I have to wade through blurts to get there. I feel better already. Mark

A PLF is an option for me under my X-VX93 (thanks GroundZero! a fabulous canopy!). A face-plant is the result of a poorly performed PLF, in turn usually the result of a rarely practiced PLF, and ultimately usually the result of poorly taught PLF. (Although if the PLF is poorly taught, lack of practice is probably a benefit.) Mark

Use the one supplied by the rig manufacturer. Mark

I've probably jumped a pack job like this a couple thousand times. I haven't experienced the 90-degree off-heading openings you suggest are routine. What are you basing your theory on? Mark

How come I've never experienced that? Mark

I am, and have been since 1983. I agree with Zoltan. Mr. Bonadies' heart was in the right place, but his actions put his student's life in greater danger, not less. Mark

Don't expect anyone to help. Mark

No. If the pilot chute is on its side, the side toward the relative wind collapses up into the opposite side, creating a hemisphere. Mark

I like a Mirage pilot chute in my Mirage, a Vector pilot chute in my Vector. It's easier to keep mesh and fabric out of the pull-up cord on either Vector or Mirage (where the material is pulled out of the coils), versus Rigging Innovations (where the material is stuffed into the coils). An all fabric pilot chute like the Vector has nearly as much drag on its side as it does upright, so is less likely to hesitate than a pilot chute with mesh, which tends to deflate if it falls on its side. But the Vector pilot chute has a higher parts count and more seams, thus is more expensive to make. So which do you like? Mark

Go for the coached jumps. I made 5 last Sunday with Hunter Roberts in Deland -- an excellent instructor. Check out the website, FreedomOfFlight.tv. I jumped with Jimmy T the previous time I was there, too. Thanks for the opportunity to give them a plug. You learn so much faster with a coach. There's no wondering about who's moving and who's not; the in-air instruction is invaluable, and the ground critique afterward gives a good basis for setting goals on your next jump. You learn more safely with a coach, too. Some very good freefly coaches move north for the summer, so don't restrict your search to the traditional Florida-Arizona-Southern California axis. Good luck! Mark

What is your source of information for this? Mark

In addition to the 3-mile light required under canopy, I'd recommend a small flashlight so you can check your canopy, and a really loud whistle in case the ground crew needs to find you after landing. Mark

It's not just a loophole; it's there deliberately, so tandem instructor candidates can do their tandem terminal jump, where the drogue throw is delayed. I did one earlier this year, and we got to 179 mph belly-to-earth before the drogue was tossed, definitely exceeding the speed of normal droguefall. Mark

USPA BSR E.4.e.(3): "Intentional back-to-earth or vertical orientations that cause tandem freefall speeds exceeding that of droguefall are prohibited." This is in the section on student skydivers, so head-down jumps with experienced skydivers are not specifically prohibited. Mark

Bill: I guess I'm still wondering about how realistic your micro-burst example is. I thought they'd be much larger. What you've described sounds almost like an upside-down dust devil, without the rotation. Mark

I'm not sure I understand this. Both canopies should turn the same amount, since they are weathervaning into the same relative wind. But the angular difference between the pre-gust flight path and the relative wind created by the gust is less for the faster canopy. Wouldn't that mean a less violent weathervane for the faster canopy? Is this a common occurence in weather we jump in? It seems like a vertical gust of 30fps (18 kts) would be hard on the jump plane, too. I was wondering also about the size of your micro-burst. Did you choose 25 feet (radius? diameter?) for the sake of your example, or is this the generally accepted size? Thanks for an excellent essay. The best explanation of turbulence effects I've read. Mark

1224 cm^3 = 75 cubic inches (or a little more than half of a 2-liter bottle of Coke). PD106R = 253 cubic inches. Mark

Okay, demonstrating geezerhood here: 2-shots: open the Capewell cover, push both button latches, pull the locking lever forward. Designed to release on the ground. 1-shots: looks like a 2-shot, but opening the Capewell cover pulls the locking lever forward, releasing the canopy immediately. Much better if you want to cut away from a malfunction, but suppose at 100' you notice that you're going backward fast, and the landing is going to hurt. You decide to open the covers of your 2-shots, so as soon as you start your PLF, you can push the buttons. Now is a bad time to find out that your 2-shots are in fact 1-shots, even though with the covers closed they look the same. 1-1/2 shots: Compromise. The wire loop allows for tight friction fit instead of button latches -- easier to cut away -- and opening the covers by mistake won't be so bad. R2: I can only guess, from what I read in Poynter. I am unfamiliar with the R2 and the single-point R2-squared. Uses the load-bearing parts of the Capewell system. R3: Also uses the load-bearing parts of the Capewell, but has fabric and velcro cover, and allows a cut away by just pulling on a wooden or plastic dowel. Center lines: lines that run from the pulled-down apex of a round parachute to the connector links. Found on PC-class canopies -- and your collapsible pilot chute! They're going to support about half the load, so need to be about as strong as the suspension lines. Tubular nylon is the most common material used on PCs, but it stretches, and needs trim adjustments from time to time. Crown lines: run from the crown of a PC-class canopy up to the pilot chute bridle, hence the name. Typically made of Type 2 suspension line sleeving (stuff we frequently use for main closing loops now), since the primary function is to provide a load path from parachute to pilot chute, and probably not required if you free-bagged your main. So I'm looking through my Poynter's manual, in the canopy release section. Who is that handsome fellow showing off the Boothwells? Mark

Easier than making or converting a set of risers: -- unfold the riser end so it lies flat -- insert a small piece of Type 12 as a buffer strip -- insert the L-bar link -- tack in place A five or ten minute job, no stitch picking or machine sewing, and the risers can be easily restored to rapide-link configuration.. Mark

Don knows the pass/fail/incomplete rate for his own courses, as do each of the course directors for their own, but only USPA knows the aggregate. Part of the problem is how to count. Suppose a candidate takes an incomplete at one course, then finishes up at another course in the next calender year. Should he count as one candidate or two? An incomplete, a pass, or both? I know one individual who took an incomplete with one course director, started another course from scratch with a different course director and took an incomplete in that course, then went back to the first course director. How would you count that? Some things I'd like to know, but we're unlikely to find out: -- for candidates starting from scratch, the pass/fail/incomplete rate; -- for candidates starting from incomplete, the pass/fail/incomplete rate; -- for incompletes, the return/non-return rate. I'd also like to know if the rates are different (in a statistically significant way) for different course directors, and if so, if that is because their candidate pools are different, or because their course performance standards are different. Mark

According to the statistics presented by USPA at the AFF Course Director Standardization Meeting on February 1st, the success rate has increased from 53% in 2000 (221 Candidates), to 71% in 2001(255 Candidates), then 85% in 2002 (244). I am not convinced that the reported increase in the success rate represents an increase in the completion rate per course. USPA reports pass and fail, but not incompletes, and the statistics are meaningless without all three numbers. You'd like to know if you are going to pass, so 85% sounds pretty good. But suppose USPA ignores incompletes, and imagine there's a course like this: -- 10 folks in class on the first day, -- 5 of the 10 earn a rating, -- 1 person fails, -- the other 4 take incompletes. I hope USPA would report this as 83% pass (5 of 6), not 50% pass (5 of 10). Otherwise, an 85% pass rate means nearly everybody makes it, and the more likely explanation for that is lowered standards, not improved preparation. So do 8 or 9 out of every 10 candidates in class the first day leave with a rating a week later? I don't think so. My observation in a number of courses over the past year is that the average completion rate in any one course is around 50%. There are ways to improve your odds, but that's a different thread. BTW, the format of practice jumps followed by pass/fail evaluation jumps encourages marginal candidates to take incompletes. Unless a candidate has made an evaluation jump, there is virtually no penalty. The previous system of collecting points on each jump, with points carried over in case of an incomplete, meant there was no advantage to continuing in another course, and so no point in taking an incomplete if you were in trouble. I'd like to know if the incomplete percentage has gone up, down, or stayed about the same over the period covering the change in evaluation systems. Mark

I am not convinced that the reported increase in the success rate represents an increase in the completion rate per course. USPA reports pass and fail, but not incompletes, and the statistics are meaningless without all three numbers. You'd like to know if you are going to pass, so 85% sounds pretty good. But suppose USPA ignores incompletes, and imagine there's a course like this: -- 10 folks in class on the first day, -- 5 of the 10 earn a rating, -- 1 person fails, -- the other 4 take incompletes. I hope USPA would report this as 83% pass (5 of 6), not 50% pass (5 of 10). Otherwise, an 85% pass rate means nearly everybody makes it, and the more likely explanation for that is lowered standards, not improved preparation. So do 8 or 9 out of every 10 candidates in class the first day leave with a rating a week later? I don't think so. My observation in a number of courses over the past year is that the average completion rate in any one course is around 50%. There are ways to improve your odds, but that's a different thread. BTW, the format of practice jumps followed by pass/fail evaluation jumps encourages marginal candidates to take incompletes. Unless a candidate has made an evaluation jump, there is virtually no penalty. The previous system of collecting points on each jump, with points carried over in case of an incomplete, meant there was no advantage to continuing in another course, and so no point in taking an incomplete if you were in trouble. I'd like to know if the incomplete percentage has gone up, down, or stayed about the same over the period covering the change in evaluation systems. Mark

Your chest mount reserve doesn't need a freebag. May not even need a pilot chute, depending on the reserve you choose -- nothing quite like hand-deploying it! Mark

I was thinking about DZs that use 3-fingers as the practice-pull prompt. There you have 1-finger is "first priority" (a number association), 3-fingers is "do 3 practice pulls" (another number association). But 2-fingers is not associated with numbers, hence the interference. Decoding the signal becomes a two-step process: first, is this a number signal or an analogue signal, and second, what does the signal mean. The interference is not as great if you use the conventional PRCP signal, leaving the student to decide just "Is he pointing, or is it time to pull?", or "Is this legs out, or what the heck is action #2?" Mark

Most canopies improve glide ratio in quarter brakes: in light winds, you'll go farther than you would with the toggles all the way up. Mark