billbooth

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Gear

  • Main Canopy Size
    190
  • Reserve Canopy Size
    176
  • AAD
    Cypres

Jump Profile

  • Home DZ
    DeLand
  • License
    D
  • License Number
    3546
  • Licensing Organization
    USPA
  • Number of Jumps
    6100
  • Years in Sport
    53
  • First Choice Discipline
    Formation Skydiving
  • Second Choice Discipline
    Formation Skydiving

Ratings and Rigging

  • Tandem
    Instructor Examiner
  • Pro Rating
    Yes
  • Rigging Back
    Senior Rigger
  • Rigging Chest
    Senior Rigger

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  1. Jeanice Dolan of Skydive Ocean City (MD), reports 5 years and 15,000 jumps with no malfunctions on their Tandem Sigmas. This involved several Tandem Instructors and a half a dozen rigs.
  2. billbooth

    Why dont reserve PCs have limiter tapes?

    I put the center line tapes, what you called "limiter tapes", in the original hand deployed pilot chute for two reasons: 1. To make the pilot chute open faster. (Without the initial "holding open effect" of a spring, the shapeless hand deployed pilot chute tended to streamer for a second or so.) 2. A pilot chute (or any round) with a pulled down apex creates 11% more drag, and could therefore be make a bit smaller and less bulky. But, opening speed was the main reason.
  3. billbooth

    JOKE OF THE DAY CLUB

    "Who's on first" will never be surpassed, but the Johnny Carson/Jack Webb "Copper Clapper Caper" routine is right up there with it.
  4. billbooth

    Semi-Stowless Bags? Mirage?

    When I started jumping, 53 years ago, one of the first things that struck me was how primitive and simplistic stowing lines in rubber bands seemed to be. There just had to be a more modern, technologically better way to do it. I tried everything, but kept coming back to the good old rubber band. It seems that, as usual, the simplest way turned out to be the best way. The "modern" semi-stowless bag is just a re-hash of the original Para-Flite reserve bag, except that we use tuck tabs or magnets instead of Velcro to stow most of the lines in a pouch. But the good old rubber band remains the best way to lock the bag shut. To quote the Bible: "As it was in the beginning, is now and ever shall be...Magnets make for great riser covers, but in this particular game of rock-paper-scissors, it's obvious that rubber bands trounce magnets. Trying to reinvent the wheel is not always a good idea.
  5. billbooth

    Pilot-chute In Tow (its just the PITs)

    Gary; Perhaps you're right. I used the term "Line Dump" (it is a rare beast, but something more easily understood by most jumpers) rather loosely to cover the litany of problems that come from high separation velocity at line stretch, such as high snatch force and the general disorganization of the pack job it produces. I just know from conversations with legendary canopy designer Theo Knacke and decades of observation, that nothing good comes from separation velocities over 50 fps, which equates to line stretch times of about 0.5 seconds for average sized sport canopies deployed at terminal. As I have written here before, it is rather easy for a jumper to determine line stretch time by simply having someone video one of their deployments. Just count frames from container opening to line stretch.
  6. billbooth

    Pilot-chute In Tow (its just the PITs)

    Pilot chute drag is very important. Depending on design and materials, the drag to two identically sized pilot chutes can be very different. This is one reason why buying any component after-market can be risky. You must communicate to the seller exactly what you will be using the component for, so that you get a truly comparable part. A correctly sized pilot chute should get you canopy to line stretch 0.5 to 0.7 seconds at terminal. (A bit slower on a hop and pop, of course.) Too big can cause line dump, and too small can cause a bag lock from lines blowing over the bag. What size rubber bands or tube stows you use, and whether you use a full-stow or semi-stowless bag can also alter your deployment time. But when you put all those considerations together, 0.5 to 0.7 seconds is what you should aim for. A pull out probably would not have made any difference in your situation, because I suspect your pilot chute, even though too small, pulled the curved pin (which should only take around 5 lbs. of force) opening the container. Your PC just didn't have enough oomph to pull the bag out of the container because of your low airspeed. Pilot chute hesitations, reserve pulls, and fatalities because of pull outs were numerous in the 70's when a lot of people first tried them. That's why hand deploys became the dominant system. When all is said and done, hand deployed systems simply have far fewer problems in actual usage.
  7. billbooth

    Old skydiving magazine cover photos

    Great Job. A trip down memory lane. I'd love to get reprints of the articles introducing the hand deployed pilot chute (Sept '76 and Nov '77) and the 3-ring release (Aug '77). Does anyone have these issues?
  8. A while ago, I got back the first rig I ever made. It contained a PC which had been packed for over 25 years. What the hell I figured, let's put a jump on it and see if it still works. In two words, IT DID! One caveat: We DID replace the rubber bands, which had long since rotted, but we did not touch the packed canopy in the bag.
  9. billbooth

    Skyhooks/MARDs

    I've said it before, but I'll say it again. After watching hundreds of videos of people cutting away from spinning malfunctions with Skyhooks, I firmly believe that the chance of reserve line twists is lessened with a Skyhook because of the speed of the reserve deployment. Line twists happen all the time on mains, and they (of course) are deployed without MARDS. "Getting stable" after a cutaway from a badly spinning main can take many hundreds of feet. While it is very unlikely that line twists on a reserve after a Skyhook deployment will kill you. It IS highly likely that hitting the ground without a fully opened reserve will.
  10. billbooth

    Solar Eclipse Jump?

    I'm missing more than I can remember...and it's been 52 years since my first jump, which by some miracle, I remember well. It's the 70's I'm a little foggy about. After all, it was the era of free love and even cheaper drugs.
  11. billbooth

    What rigs have great 3 ring padding?

    Damn you guys are getting soft! "In the old days", we really did have to contend with "Capewell Welts" from those 1 pound hunks of metal pounding us on the front of the shoulders on opening. You could actually see the bruises after a hard weekend jumping. However, this is the first time I've heard someone complain about a little bitty 3-ring biting them. Seriously, most rigs today have spacer foam under the 3-rings to help make openings as easy on you as possible. But proper harness fit, canopy and line choice, and packing technique can have an even greater effect on comfort.
  12. billbooth

    Solar Eclipse Jump?

    I did a solar eclipse jump back in March of 1970. There was a low broken layer under us, so I could see easily the moons shadow coming at us at 1,000 mph. We exited just before the shadow "hit" us. It was an amazing feeling physically as well a mentally; going from day to night and back to day, all in one jump. It was far better than just looking up at the sun. It was one of those "once in a lifetime" experiences that I now have a chance to do again, and I'm not going to miss it.
  13. billbooth

    Mirage G4 D bag stow question

    Leave as little unstowed suspension line as possible. Never loop unstowed line in your pick tray. Your side flips "dive" right back into your pack tray as soon as the bag leaves. You don't want to leave any loose line for them to entangle with. This has killed people. You may be lucky for a long time, but eventually it will get you into trouble.
  14. billbooth

    From "The RSL & Skyhook debate" article

    Please let me toss in a few statistics in favor of one of my children...The Skyhook: It has been in the field for 17 years now. UPT, Sunpath, Aerodyne, and Avocet have filmed more than 300 Skyhook test jumps. Our demo program has allowed over 700 "average" jumpers to try a Skyhook breakaway. It has been installed on over 30,000 rigs. IF we assume an average of 500 jumps on each of these rigs, we get 15,000,000 (Yes, 15 million!) live jumps on Skyhook equipped rigs. (Assume more or less if you wish, but I bet I'm close.) IF we use the USPA statistic that a reserve is used every 607 jumps, we get about 25,000 actual reserve deployments on Skyhook equipped rigs in emergency situations. (I would like to take this moment to thank my loyal customers for providing all those test jumps for me, free of charge. I knew I could depend on you.) By comparison, TSO testing requires less than 100 jumps. In responce to some people's assertions that Skyhooks can cause line twists, or that Skyhooks were never tested on today's super hot mains, let me say this: I believe that with so many uses, we can safety assume every conceivable malfunction, on every conceivable canopy combination has happened , and I can't remember many (if any) occasions where a jumper has been injured of killed by reserve line twists, whereas MANY MANY jumpers have been killed by low reserve pulls. Besides, Skyhooks don't cause line twists. By getting your reserve directly over your head in half a second, I believe they actually lessens your chance of line twists. (What did you just breakaway from after all? Probably a main with line twists. And those line twists happened just fine without a Skyhook, didn't they.) AAD's and Skyhooks are not designed to help you when you do everything right. They are designed to give you a better chance of survival when you really screw up. So saying, "I always pull high", just doesn't hold water. That said: Nothing I have ever designed is perfect. Every device has malfunction modes. Every "safety device", from AAD's to airbags has "killed" people. However, the Skyhook has had far fewer problems than either my Hand Deployed Pilot Chute or my 3 Ring release. It has truly stood the test of time.