P A R A C H U T I N G ' S N E W S M A G A Z I N E
Ask the Editor
Contents of Batch 18:
What should I get, a Diablo
or a Triathlon?
Which drop zone is the best
for CRW training?
The following questions were submitted by visitors to our Web site and answered by the editor of Skydiving magazine. .
To ask a question of your own, click here.
What should I get, a Diablo or a Triathlon?
(The following is a series of questions and answers between a reader and the staff of Skydiving. Choosing a canopy isn't easy, and the interchange shows the approach of one new skydiver.)
Q: I have 99 skydives and I have been jumping an [Icarus] Omega 175 for 40 jumps. I weigh 160 pounds without gear. I wanted to downsize to a 150 so I just ordered a [Aerodyne Research] Diablo 150, although I've never jumped that canopy or one that small. I have heard that the Diablo "flies big" -- so a 150 is more like a 170 -- and that its performance range is somewhere between an Omega-type canopy and a [Performance Designs] Stiletto-type canopy. Obviously I am not ready for the Stiletto yet. I have heard the Diablo is forgiving and not as prone to the problems that are faced with other higher performance canopies.
Have I bitten more than I can chew?
Also, I've heard that people often have to chop line twists on elliptical canopies. Should I still try and untwist the line twists until the decision altitude? Or should I immediately chop severe line twists on the Diablo?
A: The Diablo is a good canopy. But does it "fly big"? We don't think so. Like all canopies, turn rate and descent rate (in level flight and in turns) both increase significantly as surface area decreases. While an advanced design can make a small canopy "fly big" during the flare, its responsiveness and higher descent rate make it less forgiving and harder to fly than a larger version of the same canopy.
That's why we're uncomfortable with your canopy choice. Again, the Diablo is a good canopy, but, at your weight and experience, you'd be better off with one that's larger than 150 square feet.
To elaborate a bit:
When everything is going according to plan, you'll handle the Diablo well.
But in some extraordinary situations, the wing-loading you'll have with any 150 sq.ft. canopy might get you in trouble. You might land hard enough to do more than just get your jumpsuit muddy.
Examples of such situations:
* A low-altitude turn at the end of a long run back from a bad spot.
* An unexpected obstacle or jumper who suddenly crosses your flight path while you're on final approach.
* A bad spot that requires that you land in a tight area, perhaps in deep brakes, or to make a curving approach.
The wing-loading you'll have will make any 150 sq.ft. canopy a handful in these situations. Don't take this the wrong way -- we're not being condescending -- but it's difficult for anyone to accumulate enough skills and judgment in 100 jumps to make that kind of wing-loading a good choice right now.
Again, it's not a matter of canopy type; it's one of wing-loading. As wing-loading increases, so must the ability of the jumper, particularly in difficult situations.
Have you bitten off more than you can chew? Perhaps not -- with the right training, attitude and aptitude, you could make the switch now and never eat a dirt sandwich.
But, as you realize, you're upping the risk level for yourself.
We encourage you to put a few "controlled" jumps on a demo Diablo 150 before committing to it. Doing so will help you decide if you're ready to use it as your "every day" canopy.
And, yes, line twists with higher aspect ratio elliptical canopies sometimes create a situation where the only safe option is a breakaway.
Occasionally a canopy will open with badly twisted lines but it won't be turning. If that's the case, kicking out often works just fine.
But sometimes things start off well (the canopy isn't turning at first) but go to hell in a hurry when a turn starts.
The turn can quickly turn into a spiral and the spiral can quickly morph into a spin -- all in the matter of a revolution or less.
The third scenario is the canopy opens with twists and is turning. Good luck kicking out of that, especially with a small canopy. Sometimes the twists get worse!
A small (highly wing-loaded) canopy in a hard spiral loses altitude at a breathtaking rate. Many jumpers don't appreciate how fast altitude can melt away until they watch another jumper on the same load drop from the sky as he or she copes with a spiraling malfunction.
Significant "G" forces build rapidly, making a breakaway difficult or -- rarely -- impossible.
The malfunction becomes more radical as wing loading increases, too.
Although elliptical canopies seem more prone to unrecoverable line twists than rectangular canopies, we've seen the same malfunction with little rectangular designs, too.
So . . . jumpers with small canopies learn to:
1. Do what it takes to make/help their canopies open on heading. This involves packing correctly and following the canopy around as it opens, if necessary. (Freeflying was actually developed by Stiletto jumpers; they use its techniques to follow the canopy around as it inflates.)
2. Be ready to get out of line twists immediately after inflation, using whatever method(s) work. Every second counts.
3. Keep track of altitude and do not hesitate to breakaway at decision altitude. Sometimes it's inevitable -- kicking out simply won't work, even from 20,000 feet.
4. Maintain their gear, keeping their 3-Ring systems in good shape and consider adding improvements such as riser housings.
Q: I have already sent in the payment on the Diablo 150. I'm going to call and cancel my order. Weighing 160 pounds without gear, I was told by this guy who helped me get a good deal on the Diablo that I was safe jumping a 150. In fact, he encouraged me to get a 135. He has about 500 jumps so I thought he knew what he was talking about, but apparently he doesn't. I will call Aerodyne and cancel my order today.
A: Don't be too hard on your buddy. Experienced jumpers tend to forget that the sport isn't as easy to learn as they think.
Aerodyne's a good company, and the people there want you to have the canopy that's right for you -- I doubt you'll have any problems changing your order.
About a year ago we heard Airspeed had turned in its Stiletto 97s and 107s for Stiletto 120s. I asked one member why and he told me: "When you're making 1,500 jumps a year, you do not really want every jump to be an event."
Here are jumpers who often make more than a hundred jumps a month (really) and who each have accumulated several thousand skydives. Although they are quite able to handle small canopies, they'd found that it took too much effort, day in and day out, while training for the World Meet.
You'd be in a similar situation. You could handle that wing-loading on 99 percent of the jumps you made, but you'd be likely to find yourself in a world of hurt in that remaining one percent.
There really is no hurry to downsize. You can have plenty of fun with a canopy (actually, a wing loading) that is easier to handle than what you have in mind.
Again, we encourage you to demo any canopy (at the size you're interested in) before buying it. Most manufacturers and many dealers have demo programs that are pretty painless.
Q: It looks like they will switch my order from a Diablo 150 to the Triathlon 160. With my exit weight of 185 pounds that should still be fun to fly.
A: The word on the street (so to speak) is that the Diablo is a better canopy than the Triathlon. How about getting a larger Diablo rather than switching to the Triathlon?
Q. I'm sticking with the Triathlon 160. I've heard good things about it and I want a smaller pack volume than the Diablo 170 offers. I'm only going to be able to make about 50 jumps this summer and then I'm taking three months off of skydiving to backpack around New Zealand.
When I get back from New Zealand and I'm not current, I don't want to be under a really zippy canopy. After I put about 300 jumps on the Tri I'll have over 400 jumps total and be safe to fly an elliptical.
Which drop zone is best for CRW training?
Q. I am interested in obtaining CRW training from an experienced CRW instructor at a reputable drop zone with an excellent safety record and well maintained CRW equipment. Do you know of any drop zones that conduct novice CRW training on a regular basis? I live in British Columbia, Canada, but I'd be willing to travel.
A. Both Kapowsin Air Sports in Washington and Perris Valley Skydiving in California have active CRW jumpers and offer CRW instruction.
Most of the training at Kapowsin is provided by the U.S. National 8-way team "Team Infinity," although they're not always available due to their training schedule. The team is practicing hard now for the World Championships in Finland and jumps at both Kapowsin and Perris.
Perris offers more formal programs, with CRW trainers and coaches on staff. You'd have to travel farther, but you could probably set up a training time to better suit your own schedule. Square One, an equipment dealer located on the drop zone, offers CRW gear for rent.
Kapowsin's telephone is (360) 893-3483. Perris Valley is (909) 657-3904. You might also try SkyDance SkyDiving in Davis, Calif., (530) 753-2651; or The Parachute Center at Lodi, Calif., (209) 369-1128.
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