mark

So, um, where does the tether go when they release the drogue? Mark

Wouldn't have mattered if he did, it would still be wrong. The only way to get 45 degrees or more is for the vertical speed of the jumper to be less than the horizontal speed of the airplane. That occurs twice: once immediately at exit, and second after canopy deployment. Using the first occurence of 45 degrees is unsafe; using the second is uneconomical. Mark

Fingertrapping the excess brake line shortens the steering line. The effect is less pronounced on smaller Spectra lines (PD reserves), more evident with Dacron (Precision, PISA). The position of the knot or fingertrapped loop must be adjusted accordingly. Even if you are using the knotted-loop method without fingertrapping the excess, you stiil need to check that the finished length is correct because the knot itself shortens the line. Especially on large-diameter line, having the factory mark at the toggle grommet results in a length slightly off. Mark

I'm partial to the Pink Skyvan, too. Mark

No better paint job than the Pink Flamingo. Hands down. Mark

You'd need to have the pitot heat on to prevent jumpers from using the pitot tube as a floater handle. You'd probably want to have the master switch and mag switch (keys), and fuel boost pump switches moved to the center or right side of the instrument panel, to prevent assistance from tandem passengers. Also, there might be a situation where it would be handy to get to the fuel primer. All four of those things are typically on the left side of the panel. After that, it's just a question of the pilot getting comfortable flying from the right seat, with flight instruments on the opposite side of the panel. Flight instructors do it all the time. Mark

Just great! Thanks! (For those of you wondering, MEL provided a chipset that allows my electronic bartacker to reproduce most of the patterns in common use in the industry. The standard chipset is ok for most repairs, but now I get to try for that little bit extra that's the difference between merely adequate and factory standard.) Mark

I don't think Derek needs me to defend him, so I'm here on my own account. The TSO requires some, but not all, instructions to be provided to the user. Oddly, the installation instructions, which the FAA recognizes are important for installation, are not among those required to be provided to the user. In the FAA's usual meaning, "user" would be "operator". For us, that means skydiver/owner, not rigger. Instructions are provided to the purchasers of equipment, not riggers. Otherwise, you owe me copies of all the Icarus manuals. In any case, the TSO is a manufacturing QC document which imposes requirements on the manufacturer. The TSO is silent on the obligations of the user. I can see where manufacturers would want you to follow the instructions; you are right when you say the FARs require us to follow the instructions. However, the FARs are silent on the question of how available the written instructions should be. Mark

Have you looked at the "Made in" tags on your PD Slink™tabs? Mark

If by "leather look" you mean that stuff left over from the basketball factory, it looks okay on some parts of the rig, not so good on others. It doesn't stretch or move like para-pack or cordura, so it's harder to make basketball-stuff reserve side flaps look good, and anywhere else the two fabrics join you're likely to get puckering. It's also thicker than the usual fabric, so the tuck tabs don't work as well. Houndstooth holds up okay, but please don't use it on the reserve pilot chute hat -- it's a real pain trying to get the pilot chute collapsed so the pattern aligns with the pattern elsewhere on the rig. Mark

I tried Tandem Slinks™ on our tandems last year or the year before. I didn't like the result, and went back to Rapide™ links. With Slinks™, the sliders stopped with the grommets in contact with the risers an inch or so below the riser tops, and the "polishing" effect moved from the EZ384 sacrificial lines to the risers. I wound up replacing risers much earlier than I wanted: except for the weakened, polished/brittle area at the top, the risers were in good condition. Mark

Don't keep us in suspence. What did you decide? Mark

Sunpath calls them "dual cutaway risers," and the system is a "dual cutaway system." "Universal risers" would connect to my capewells, tapewells, and my 3-rings, and to a host of other riser receivers. Mark

Bill Von -- Thanks for the video proof that the 45-degree angle method doesn't work. Now we have this variant. What education and proof technique would you recommend? Mark

And they last a long time, too. A lot longer than Vectran. Mark

I just finished replacing the HMA linesets on my X-FX99 and X-VX93. Easiest relines I've ever done -- no fingertrapping, no sewing, no bartacks. New lines clearly marked; all I needed to do was larks-head them in place. Thanks, Precision! Mark

I've always found it difficult to tell which students would get to the point where they buy their own gear. In the US, only about 3% of static line FJC students make it to an "A" license; AFF does considerably better. Still, most students will never get their own gear. Any transition adds risk. Folks who prefer SOS for their students have chosen to minimize the risk at the biggest transition of all -- from whuffo to skydiver -- in exchange for slightly elevated risk to those few who make the transition from student gear to their own. Mark

I just repacked a PD 143 made in 1989. It's easy to forget how long that design has been in production. Conversely, Flight Concepts reserves continue to be offered today. Instead of looking at just the date of manufacture, check the date of design. Glidepath/Flight Concepts reserves were state-of-the-art once, but the basic design is from 1980 or so; ditto the Pegasus-derived Raven mains/reserves. PD reserves are a generation later. Mark

I never did see the movie version of "The Hotel New Hampshire," mostly because I thought the book was wickedly good, and I didn't want it ruined by the bad flavor of a poor movie adaptation like "The World According to Garp" (in which Robin Williams plays yet another variation on ... Robin Williams). John Irving manages to have hilarious scenes in most of his books, but my favorite is the Christmas play in "A Prayer for Owen Meany." That book is for me the most intriguing of all he's written, one that I re-read every couple years. Thanks for reminding me. Mark

I have seen a diaper-deployed round reserve open with a full inversion, then landed safely. Does that prove or disprove your point? Mark

After doing the calculations, I find that the average G-force in a skydive is 1.0 even if no parachute is used. That's the same G-force as just standing on the ground. Why bother with all that nylon? Mark

I like the X-mod on my X-FX99 and X-VX93. Peformance issues aside, my HMA lines last longer than Vectran. And when I re-line my canopies, I won't need a rigger to fingertrap or bartack anything -- all the lines are larks-headed at the attachment points. In exchange for a little more $ up front, I save a lot later on. Mark

MRVS is located between Henrietta and Lexington, Missouri; about two or three miles to either. Skydive Kansas City is in Butler, Missouri. Not in Kansas. The average wind speed in that area is about 20% greater than Florida (excluding Key West). According to data provided by the city of Henrietta, the average wind speed is greater than 10 mph (exceeding the BSR limit for students equipped with round reserves) 8 of 12 months in the year. Consider also that winds at night are generally lower than during daytime. Every airport has some obstacles around it, such as airplanes, cars, hangers, electrical lines, roads, fences, ditches, etc. MVRS is in the Missouri River valley, close enough to the river to have been flooded in 1993. Obstacles which a square-equipped jumper doesn't think twice about can be hazards to someone jumping a round. I've used a round reserve in Kansas. It wasn't much fun, and I don't think I'd have enjoyed it any more if I'd used it in Missouri. Mark

So I checked the USPA dz directory, and found links to Skydive Kansas City in Butler ("perfect safety record") and MRVS ("more experience"). Hmmm. Is not all peace and love in the KC area? I think you're seeing "It's a feature, not a bug!" If I had to guess, I'd say that MRVS is in the process of converting to all square reserves, but isn't there yet. Their website says their freefall rigs have square reserves. It may be true that in a two-out situation, round & square is better than square & square. However, most student malfunctions are of the single-canopy variety: didn't like the first canopy, gonna get rid of it and try a different one. If you have an emergency and need to use your round reserve, you still have an emergency. Square reserve canopy control is similar to square main canopy control, so no new techniques to learn under stress. Square reserves give a greater choice of landing areas. Square reserves allow landing going forward in most wind conditions students are likely to jump in. With a round reserve, you are likely to land going backward (unless you land downwind, which is not an improvement). Round reserve landings should be done with a PLF; I haven't seen many civilian instructors capable of doing PLFs, let alone teaching them. Bottom line: in the most likely scenarios, a square is much better than a round. Rounds are inexpensive -- I can't get any takers at $200 for an airworthy round reserve. And rounds don't have freebags, so there's less to lose if a student has a cutaway. Mark

That's three things. The reinforcing was just at the line attachment points. Mark