Gary73

Yes, but I think he was asking about turbine vs. diesel engines, not jet-fuel vs. diesel-fuel diesel engines. There may be a few specific exceptions, but in almost all cases the diesels are heavier. The Thielerts, for example, are heavier than the Lycoming and Continental avgas engines that they are intended to replace, and the Thielerts are brand-new technology while the avgas engines are 1930s technology. Yeah, diesels have that reputation, but the Thielerts don't seem to be living up to it yet. Maybe in a few years. Don't get me wrong: diesels have their place, and maybe even in some long-range aircraft; I just don't think they're a good choice for jump planes. "Extraordinary claims require extraordinary evidence." - Carl Sagan

Actually turbines use a glow plug or spark plug ("igniter") to get the flame going. After startup that system is shut down, since the flame in the combustion section is continuous, kind of like in a gas or oil furnace. For any given power output, diesel engines are heavier than gasoline engines, and way heavier than turbines. From an engineering point of view, the main advantage to a diesel is the lower fuel consumption per horsepower, so diesels are a good choice for long flights, where the lower fuel weight makes up for the higher engine weight. I'm not sure they'd be a good choice for jump planes, where fuel tanks are rarely filled and the plane spends most of its time climbing, where weight is so critical. I'll stick with a nice PT-6 turbine, or better yet, two oversized ones on a King Air. Once you're used to nine minutes to fourteen grand, anything slower is torture. "Extraordinary claims require extraordinary evidence." - Carl Sagan

From the CYPRES manual: If a jump plane is descending without having dropped, switch the Student CYPRES off! Unlike the Expert CYPRES models, we recommend that the Student CYPRES be switched off in the aircraft prior to descent if the jump is aborted and the student will land with the plane. Be aware that it is possible to exceed a vertical speed of 29 mph under a fully inflated canopy! The problem is that once the descent begins, the AAD doesn't want to shut off, which is understandable. In that case, it's very important to tell the pilot to keep the rate of descent less than 1000 feet per minute below 2,000 feet AGL. I''ve been on the DZ for at least four such cases with student CYPRESs. Everything stayed in the plane; no injuries. A few years ago, however, there was a fatality (in Europe, I believe) when a student AAD fired and pulled an observer (or maybe co-pilot?) out of the plane. The AAD functioned exactly as documented; it just wasn't used as intended. So yes, unintentional firings do happen. What I'm trying to get a feel for is the proportion of intentional (partial malfunction) student AAD firings to unintentional ones. Please don't misunderstand me here: AADs save lives. I have two rigs, both have (Expert) CYPRESs, and I wouldn't have it any other way. But at the same time, every safety feature has drawbacks which must be understood in order to be minimized. "Extraordinary claims require extraordinary evidence." - Carl Sagan

Student AADs are supposed to fire at 1,000 feet at descent rates over 29 MPH to protect students who haven't cutaway from a malfunction that's fast enough to hurt or kill them but isn't anywhere near the 78 MPH firing speed of an expert AAD. Unfortunately, that speed range can easily be reached by performing spirals or making fast descents in the plane, which can result in an undesired and possibly dangerous two-canopy-out situation. I've seen several cases of the latter over the years, but none of the former. What I'm wondering is how often student AADs fire for the intended reason instead of the unintended one. So if any of you have actually been on the dropzone when a partial-malfunction student AAD firing occurred, I'd appreciate if you would tell us about it. Please also give an estimate of how many "undesired" student AAD firings you've witnessed. Thanks. "Extraordinary claims require extraordinary evidence." - Carl Sagan

They're too much trouble for me to make and I don't have detailed plans, but you're welcome to copy the design. The 3/16" aluminum for the base plate, 1/2" plastic for the frame, and motor/worm-gear assembly (windshield-wiper unit) are from eBay, the switch is from Radio Shack (momentary DPDTCO), and the 14.4V battery is from a drill/driver. All held together with countersunk 1" deck screws and gaffer's tape. Tension is a matter of how long you hold the switch down. The unit is less powerful than a manual torque-tube unit, so it shouldn't be any more likely to cause rig damage than any of the other tools out there. In other words, it's not a substitute for good packing, it's just a time and labor saver. "Extraordinary claims require extraordinary evidence." - Carl Sagan

Well if the younguns have you feeling old, you're always welcome to hang out with us old folks. Might make both you and us feel younger! "Extraordinary claims require extraordinary evidence." - Carl Sagan

Somewhat to my surprise, I do have the gear (and plane), but no, I'm not at all interested in partnering (in any way!) with Bill. As for going back if Bill opens up there again, no, I'm not too interested in that, either. Too many issues with Bill as a DZO. As for those former SDM regulars who still don't feel at home elsewhere, a dropzone is largely what we make it, so be a part of making your new DZ what you want it to be. And there's also the matter of acclimating yourself to what other people have already created. Of course to do these things you have to actually go to the dropzone and preferably make a few jumps, too, so let's see more jumping and less moping! "Extraordinary claims require extraordinary evidence." - Carl Sagan

I guess I've never understood the resistance to using improved tools. Is it just a matter of "I had to do it the hard way when I learned, so everyone else has to do it the hard way too!"? At the same time, I really wish that the creators of manually operated devices wouldn't use the word "power" when naming said devices. With every other type of tool or appliance, "power" implies the use of some outside power source, like electricity. Now if you want to see a real power closer, check the attached. "Extraordinary claims require extraordinary evidence." - Carl Sagan

There were a couple of related threads about four years ago, but I wanted to have a poll. BTW, 60 miles in 45 minutes? Damn! "Extraordinary claims require extraordinary evidence." - Carl Sagan

Sort of skydiving related, in that it's one measure of a jumper's devotion to the sport: How long does it usually take you to get from your home to your home dropzone? "Extraordinary claims require extraordinary evidence." - Carl Sagan

Just happen to have this handy since I'm running a course in a couple of weeks: Before attending the course, candidates must have: at least a B License and at least 100 freefalls, observed and assisted with one complete First-Jump Course, a Skydiver’s Information Manual* that's less than 2 years old, an Instructional Rating Manual* that's less than 2 years old, become familiar with the relevant SIM and IRM sections, and completed the Coach Written Exam (in the IRM). At the course, candidates will: Attend a day or so of class and conduct training sessions to teach several basic skydiving skills. At or after the course, candidates will: perform two or three simulated ground preps and coached jumps with Evaluators. Before or after the course, candidates must: teach the general portions of two First-Jump Courses under the direct supervision of an Instructor. Upon receiving the rating, Coaches can: teach the general portion of the First-Jump Course, make regular or coached jumps with students who have been cleared to self-jumpmaster, verify (but not sign!?) A-license card qualifications, and work toward qualifying for Instructor ratings. * Available at uspa.org BTW, the IRM Essentials "manual" doesn't really live up to it's name. It only includes the introduction chapter for each rating. Not even remotely close to what's essential to attend the course. "Extraordinary claims require extraordinary evidence." - Carl Sagan

A number of Boenish's old films are available through http://www.skydivingvideos.de/ but only in PAL format, last time I checked. There are companies (and rare individuals) who have conversion equipment. Ask around among the video folks at your DZ. It's a shame that the owners won't make the older stuff available in NTSC format, but I guess there's too little demand. "Extraordinary claims require extraordinary evidence." - Carl Sagan

First look at the attached photo of Atlanta International Airport, which is the busiest airport in the entire world. I used this photo as wallpaper on my office PC for a while since my office was at about the 2:30 position in the photo, I've always liked aviation, and I worked for an airline-related company. A co-worker, knowing that I was a skydiver, once asked: "Oh, is that the airport where you skydive?" "Extraordinary claims require extraordinary evidence." - Carl Sagan

David, It's a bit of a drive, but a lot of folks from the Augusta area jump at Skydive Atlanta in Thomaston, GA ( http://www.skydiveatlanta.com/ ). We use the standard 7-level AFF program, like almost every turbine dropzone, but I'm sure we can work something out. BTW, the video looked pretty good. If that had been an AFF 3 I'd have passed you on to 4. Try keeping your knees a little closer together. That will allow you to have a deeper, more relaxed arch, which should smooth out that rocking. Take care, Gary "Extraordinary claims require extraordinary evidence." - Carl Sagan

It will take your rigger less time to show you how to do it correctly than it would take to describe it here, and since you need to have your work checked before you jump it anyway... "Extraordinary claims require extraordinary evidence." - Carl Sagan

I mainly agree with you. I'd like to see more canopy-control instruction in both the FJC and in later ground preps. I'm going to one of Scott Miller's courses next weekend mainly in hopes of learning how to teach CC better, and if I learn something new myself, all the better. As for why anyone would end up over a bad area to begin with, you touched on one of the reasons: larger planes make it impossible for everyone to get the ideal spot. Other reasons that don't imply improper behavior on anyone's part might include: First load; winds not as forecast Winds changed since last load Tracked in inconvenient direction Flew wrong direction under line twists Cutaway caused lower opening altitude As for not flying over bad areas, I'll have to visit Queensland one of these days - I've never seen a dropzone that didn't have at least a few bad areas! WRT Instructor responsibility and authority, yes, but a spot that's good enough for one student might not be for another. Lots of students do a great job in front of the overhead photo, then get totally disoriented in the air. Last Fall I saw a professional pilot fly directly away from the airport until I turned him around. Twice. "AFF is like a box of chocolates - you never know what you're going to get." "Extraordinary claims require extraordinary evidence." - Carl Sagan

Andy, Glad you got it out okay - you've had enough excitement lately! "Extraordinary claims require extraordinary evidence." - Carl Sagan

How tight should a BOC pouch be? That is, what are safe minimum and maximum forces for pilot chute extraction? I think I know it when I feel it, but are there any objective standards? I'd like to be able to give my customers more than just an opinion. Thanks "Extraordinary claims require extraordinary evidence." - Carl Sagan

AFF graduation. "Extraordinary claims require extraordinary evidence." - Carl Sagan

What kinds of policies and prices do dropzones out there have for the rental or use of dropzone equipment like jumpsuits, helmets, altimeters, gloves, and goggles? Does it depend on whether the person did their student training there? Does it depend on whether a rig is being rented at the same time? I'm curious because we just got a new policy: Jumpsuits will not be available to anyone after graduation. Period. A jumper/ new graduate must purchase an altimeter [by] the first jump weekend after graduation. A new graduate may use a helmet and altimeter the weekend they graduate but not a jump suit. Out of state jumpers with no access to their gear will be able to rent a helmet and altimeter at a rate of $10 per jump. "Extraordinary claims require extraordinary evidence." - Carl Sagan

? "Extraordinary claims require extraordinary evidence." - Carl Sagan

Dontiego, Yes, that's exactly what I meant. Who cares how far down the beach you land, as long as you do land on the beach and not in the water! "Extraordinary claims require extraordinary evidence." - Carl Sagan

Andy, Any time, man. See you at Dublin! Doug, Yes, your ground speed would increase, but the increase would all be down the wind line instead of across it, which is the goal in this particular case. (See attached second diagram.) John, I guess I don't understand. The drawing is a view from directly overhead, and the arrows are intended to indicate the directions the canopy is pointing and the wind is blowing. Perhaps the second diagram is clearer. Sorry, I'm not much of an artist and Microsoft Paint isn't much of a diagramming tool... WRT the second diagram (attached to this post), when you're flying a canopy, your movement through the air (glide) and the air's movement over the ground (wind) are happening simultaneously, but sometimes it makes the situation more clear to draw them one at a time. In this case I drew the wind movement first, then the glide movement starting where the wind "left off". Examples are given of an upwind crab, a downwind crab, and a perpendicular (to the line separating the good area from the bad area) crab, with the dotted lines showing the actual movement over the ground. (Geeks will recognize this as a crude description of elementary vector arithmetic.) From that starting point, the canopy pilot can get to any point inside the Glide Range circle, but only a small portion of that circle is in the safe area. Note that this case shows a strong wind parallel to the separating line, but the same rule applies regardless of wind speed or direction: point the canopy perpendicular to the separating line to get the most movement toward the good area. BTW, thanks, all: As is often the case, explaining this has caused me to re-think and hopefully improve how I teach it. "Extraordinary claims require extraordinary evidence." - Carl Sagan

Gary, Yeah, it's important to stay flexible in this sport, isn't it? Sometimes we forget that and focus too much on the original plan when there's a better answer right in front of us. Or right behind us! Stratostar, I've heard good things about the Parasim but never had a chance to use one. Too bad they're so pricey. FFG, I definitely agree about using overhead photos for both regular and "what if" canopy-control scenarios. In fact I just recently made some new ones for our DZ. Fortunately, Google Earth makes it pretty easy to get good images of most of the U.S. Their coverage of Austria isn't very high-resolution yet, but from what I can see it looks beautiful. I'll have to get over there someday. Rob, Funny that you should use that analogy: The first time I remember using this technique was after a cutaway a couple hundred yards out over the Gulf of Mexico with a strong wind blowing along the shoreline! Unfortunately, sometimes people focus so much on getting to the original target that they fight a losing battle crabbing across a strong crosswind and come up short. Glad to hear that others are teaching this technique. I generally agree with the standard method of moving the whole downwind/base/final landing pattern to a safe area when you can't get to the original target, but sometimes it takes all the running, holding, or crabbing you can do to get to a safe area. Sometimes you even have to skip that last turn and land downwind or crosswind to get to a good area, so it seems like a good idea to make sure that students (and radio Instructors) are aware of their options. "Extraordinary claims require extraordinary evidence." - Carl Sagan

Sometimes it happens that you find yourself under canopy over a large bad area (trees, water, etc.) on a day when the wind is parallel to the line separating the bad area from a large good area. The tendency is to crab toward your original target, but if the wind is close to your glide speed, you may not cover enough ground to make it to the good area before you land. On the other hand, if you turn perpendicular to that separating line, you'll make the best possible progress toward the good area, even though you may end up a good way downwind of your original target. (Please see attached diagram. And yes, that's about the limit of my artistic ability!) Is anyone else teaching this or using it while giving radio guidance? "Extraordinary claims require extraordinary evidence." - Carl Sagan