mark

I recently came across a series of posters intended as visual aids for a static line FJC. I vaguely recall these being used in my FJC, and maybe you do too. These black-and-white posters have stylized figures (not photos), and show things like student position on the step, initial position ("hard arch"), a round canopy with arrows indicating airflow through drive and turn windows, and PLFs. Each poster is marked "United States Parachute Association Publications" and "Paravisualx™ © 1975 John F. Sorensen." I have 10 posters; I'd like to know if that's the complete set. Yes, I've contacted USPA. Thanks, Mark

Unless the pouch is rigid and airtight, holes are unnecessary. The pressure inside will equal the pressure outside. Katze: Tell me again why this altimeter glove is a better arrangement than wearing an altimeter and (optionally) a glove. And what are the fingertip controls going to do? Will I be able to hold something and still work the controls? Conversely, if I don't want to work the controls, will I still be able to hold something? Mark

ISP Cat A is silent about flaring or not; Section 5-1 (for experienced jumpers) recommends "minimal control input for landing," but doesn't say beyond that to flare or not. I'd recommend against students flaring either canopy in a 2-out biplane. Flaring takes you from a configuration we think is landable (bird-in-the-hand) to a configuration that might be better or might be worse (two-in-the-bush). If the canopies are not exactly one behind the other, would stalling the front canopy cause an asymetrical wrap and then a spiral in? I don't know; perhaps an intrepid dz.commer can do the test jumps for us so our students don't have to. In any case, a student's approach speed is likely to be low because of all that fabric out (400-500 square feet; I concede it's not the same as having a single huge canopy), so flaring isn't likely to have a great effect on forward speed or lift. Mark

If you are referring to flaring a CRW biplane for landing, I think it's apples-vs-oranges. To the extent that a student might think it applicable to a personal biplane I think it is bad advice. I agree that in a stable biplane, the main canopy is a keeper. In the one 2-out biplane I've seen, the main risers snagged the reserve after cutaway, but thankfully cleared. Oh, yeah. My only 2-out jump was with rounds, giving JCC/ICC candidates something to critique. A story for another time. Mark

Several years ago I was working with a couple AFF candidates at a pre-course at Titusville/Space Center. We were climbing through 8000 feet, over the swamp several miles west of the dz on our way to altitude in a moderately full Viking Express (that is, well-maintained) Caravan. There were no tandems and no real students on board, so we would be last out. The group prior to us was also a pre-course jump: a pair of candidates and Glenn Bangs acting as the student. I was zoned out, thinking about my dive plan, when I was startled by a loud bang from the front of the airplane, and I felt the nose pitch down to level flight or a little lower -- best glide, perhaps -- not much, but abrupt and distinct. The pilot was definitely in control, though, and the plane was still flying. I thought to myself, "Wow! I wonder how Glenn got the pilot to simulate an emergency like that! I'll have to ask so I can use it in the actual course." I didn't have a lot of time to think thoughts like that before I heard lots of folks yelling "Get out!" I was a good student. I waited for my instructors to tell me what to do. I was hoping we'd at least get in a practice exit, but no, my guys just left me behind while they bailed out. I didn't have any good ideas, and it seemed like the pilot was doing okay without my help, so I bailed out, too. In freefall, I looked for other jumpers, saw I was clear, thought briefly about practicing some freestyle stuff, then decided that being over the swamp merited pulling high. I still well above airplane landing pattern altitude when I got back to the airport, so I checked the approach paths, crossed above the runway and landed in the experienced area next to the hanger. I should not have set a bad example; other jumpers also landed in the same area, the last few of whom must certainly have flown right in front of the Caravan/glider, who most certainly did not need the additional distraction. The pilot was carrying a little extra airspeed, but he got his airplane stopped before the end of the runway. The tires were ruined, but cheap compared to bringing back the airframe safely. Inspection showed that one of the engine bearings had gone out prematurely; the resulting wobble allowed many of the turbine blades to contact the shroud. The engine was basically shot. It wasn't something Viking Express, Space Center, or Glenn Bangs could have predicted. It was a fun AFF course. Thomas Lewetz brought his kids and a bunch of the Pink Skyvan crew, lots of folks earned ratings, and I found out Dunkin' Donuts really does serve coffee in a box. Mark

John: Of the 50 biplanes you've landed, how many were personal (2-out) biplanes? Of the 2-person biplanes you've landed, how many were landed still in biplane configuration (top guy's feet still in the bottom guy's lines through touch down)? How many were landed by flaring only the front/top canopy, without the bottom canopy flaring at all? Mark

Would this Jump Shack article, Rubber Bands Break for a Reason, qualify? Mark

Initially, the locking stows need only be tight enough to retain the lines until the canopy slumps inside the bag as the bag lifts off. Then the weight of the canopy against the stows is usually enough added pressure to keep the stows secure. Locking stow tightness isn't likely an issue here, though: the D-bag is smaller than before. Either way, I'd be surprised if "line dump" (canopy-first deployment, actually) is to blame. In addition to the new D-bag, there's a new pilot chute, isn't there? Mark

I have several recent jumps on a 9-cell Para-Foil 282. it is the only canopy I've jumped that opened hard and had end-cell closure at the same time. It seemed like the brakes affected only the forward speed of the canopy. Flaring for landing resulted in very low forward speed, very little swing forward, and very little change in descent rate. I don't have much experience with accuracy canopies, but I think these flight characteristics would be desirable for accuracy with a tuffet or pea gravel target. A smaller canopy would allow you to land going forward in higher winds than a classic accuracy truck optimized for winds within compeition rule limits, and modern non-accuracy designs are more likely to allow softer landings than a canopy intended for thumping gracelessly onto a tuffet. Stable in deep brakes is not the same as soft-landing. Mark

Strato-Flyer was the main canopy version. The Safety-Flyer reserve had no provision for pilot chute attachment. Mark

Except http://142.26.194.131/aerodynamics1/Drag/Page6.html Mark

Might want to rethink that. For example, http://www.grc.nasa.gov/WWW/Wright/airplane/dlrat.html. It's a glider, not an airplane, and similar diagrams are found in most elementary references for aspiring glider pilots. Even if it were an airplane, a diagram of the four forces acting on an airplane in flight is just a convenient simplification of what is actually going on. For example, the actual lift vector is not perpendicular to the line of flight. It slants aft; the difference between the actual vector and the vertical one usually depicted is induced drag. Mark

While you're there, make a donation. The service may appear free to us, but Jim can keep it running only for so long while he's absorbing all the costs. Mark

These altitudes are considerably higher than ones I've heard suggested at many of the dropzones I've visited. Can you tell us what factors you considered when choosing these altitudes? Do the instructors at your dropzone agree, or are you free to choose what you think is appropriate? Your profile says "AFF Jumpmaster" (a non-USPA rating); would you recommend these altitudes for a Level 8 or Category G/H AFF student? How about for static line or IAD students? Mark

Assuming the Javelin is FXC-ready, installation = assembly. If the rig does not already have a pocket, channels, mounting bracket, etc., where would one find drawings and diagrams for this alteration (besides Sunpath)? Not that I would recommend such an alteration. I don't think it's cost-effective. Just curious. Mark

Just to be clear, I am suggesting a change to the topmost classified page (http://www.dropzone.com/cgi-bin/classifieds/page.cgi?d=1), the one that lists the different classified ad categories, starting with AADs and Aircraft, ending with Videos and Wingsuits. I think the pages listing the ad summaries in each category are fine. For example, this is okay: http://www.dropzone.com/cgi-bin/classifieds/page.cgi?g=Jumpsuits%2Findex.html&d=1. I don't think a time limit is necessary. If I haven't checked jumpsuits for several months, they're all new to me! And the ads are already sorted by date. By analogy: it's been a while since I visited the CRW forum, so my topmost forum view shows quite a few unread CRW threads. If I check the forum, the threads will be sorted by date of most recent post, I can choose how stale a thread I want to go back to, and when I return to the topmost forum view, the unread thread count is reset to zero. Thanks, Mark

Right now, a "new" classified ad is one recently posted. To find out if there are listings I haven't seen before, I have to choose a category. Could the "new" tag be changed so it's more like the unread thread count on the forums: to show only if there are new ads added since the last time I checked a category? Example: -- old way. Click classifieds, see all categories. "Reserve canopies" shows "new." Click "Reserve canopies." Nope, still shows same ads from yesterday. -- proposed way. Click classifieds, see all categories. "Reserve canopies" has no listings added since I checked yesterday. "New" does not show. I save a click and page view; when I save enough clicks and page views, I have time to make an extra jump. Mark

The field-replaceable cutter coupler can rotate without disconnecting. But you're right: the cable channel and coil(s) usually have enough slack that the cutter can be pulled through the elastic, allowed to relax, and then be pushed back into place. Mark

http://www.randi.org

In addition to the marking on the diaper, your Phantom 26 has serial number, date, and some other information on Gore #1. It may also have a zillion stamps and signatures certifying acid mesh tests. I'd be surprised if anyone switched diapers, since diapers are somewhat sensitive to canopy volume and line type/length. Low-porosity reserves were an improvement over Army/Air Force/Navy reserves converted to civilian use back in the day. IIRC, Phantoms are F-111, a further fabric improvement. I don't think I've ever heard of a Phantom described as a Lopo. Mark

The question that should come before this: has anyone with a line-over malfunction on his or her main been able to identify exactly which line it was, and having identified it believed they could have cut it without damaging adjacent lines? Mark

[Thread drift] Better price, better selection, better service, more convenience than Continental, McElfish, and other competitors back in the day. Mark

1988 was before Cypres. Has Javelin been retrofitted for an AAD -- pocket, cable channels, control unit window? Does it have an RSL? Where is the pocket for the main pilot chute? On a leg strap, or on the bottom of the container? Another poster mentioned SPSB 03032000, modification of the main closing loop retainer. On a 1988 Javelin, compliance requires replacing the main closing loop retainer, a more complex procedure than your garden-variety rigger is capable of. Does it have soft (fabric) cutaway cable channels, or flexible metal housings like your student rig does? Some riggers choose not to deal with 20-year-old equipment, which this will be soon. What about the riggers in your area? Would your exit weight in pounds be less than the number of square feet in the reserve? Mark

Or spend less on production and inventory costs (don't need to make three different Cypres types); don't need to do market research to figure out how many of each type to make, just how many to make overall. Mark

You shoud be more concerned about canopy stability in turbulence. In general, as front riser pressure decreases, vulnerability to collapse in turbulence increases. Mark