New skyball (deploys load if not caught)

[kallend 1,623]

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Assume the density of sand is roughly 1/8 the density of lead, then to have the same mass, the ball would have to have 8 times the volume, but then its diameter would have to be twice what it is now, which makes it have more drag, so it would actually have to be more than twice the diameter of a lead filled one (argument is for spheres, not cylinders or torpedos....)

Density of silica sand = 2.65 g/cm3

[masher 1]

Pb is 11.35 g/cm^3.

So its only 4 and bit times less.

Assuming these densities, a sand ball would have a radius ~1.6x a Pb ball.

ie sand = 5cm, Pb = 3cm

--
Arching is overrated - Marlies

[Zennie 0]

I assume you have charts in the manual for dialing in fallrates by manipulating the weight of the shot and/or length of the streamer?

- Z
"Always be yourself... unless you suck." - Joss Whedon

[SurfFlite 0]

Yep, charts we have.

Also I would like to take this moment to appologize to all the lead heads. I was assuming that it was lead shot. We bought the shot at a hunting store and after hearing all the anti lead comments I read the damn bag and it is LEAD FREE. You can all spleep well now.
websites up also, check it out.
http://www.surfflite.com/vladiball.html


FYI, the balls come empty, the weight is your responsibility. We recommend LEAD FREE number 8, 9 or 10 hunting shot.

Also you always fill the ball full and use the tail length to alter fallrates. If the ball is only say 1/2 - 3/4's full it makes the ball move away from you as you try to grab it. Similar to having your hand in water and reaching for a bug on the surface. The full ball has the proper density to eliminate this action.

Kerry

[cpoxon 0]

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The ball has been patented.

Kerry, what's the Patent number?

[SurfFlite 0]

Patent # P-295/01

It is a Yugoslavian patent. International patent is pending. I am not the inventor of the Vladiball. I am the sole US distributor.

Kerry

[fudd 0]

Sounds like a great safty improvement to skyballing. However, since it is a mechanical device, it can fail. We don't trust the cypress to save us either. Exercising the same precautions as with a regular skyball will be a good idea I think.

One question: Will the ball break if you don't catch it, so that you have to buy a new one? (assuming the unlike event that you actually find it...)

Some skyboards are equipt with sirens to make them easy to find. Maybe that would be possible improvement too?

There are only 10 types of people in the world. Those who understand binary, and those who don't.

[wildblue 4]

Fix the webpage, can't see pictures. You can probably see them though, the links are stuff like file:///E:/Aptiva%20D%20Drive/VailAir/Vladiball/vladiball%20logo.jpg

it's like incest - you're substituting convenience for quality

[SurfFlite 0]

Try it now.

http://www.surfflite.com/vladiball.html

Kerry

[GrumpySmurf 0]

Dumber question - what if someone on the ground is looking up (as frequently happens with whuffos on the edge of a landing area watching deployments) and gets the shot in an eye after some 'newbie' lets the thing get away from him/her? Will everyone outside, on the ground, now be required to wear eye protection when these things are in the air?

[SurfFlite 0]

At Skydive Arizona they have designated a ball drop area. It is at the south side of the DZ out past the student landing. You can easily make it back to the main landing area after your jump. Every test jump was made out in this area. There were people on the ground looking up at the test balls. Balls were dropped from just over 2000 ft simulating a ball that accidentally falls from your hand as you stow it. Balls were set to open at 3500 feet and filmed as they opened. Balls were set to open at 6000 ft. All the while there are people on the ground intentionally looking up (granted we were nervous people) These test were each performed many times. The plastic ball assembly landed pretty much straight down from where it was dropped everytime. The shot was so scattered that only a couple of shot even hit anyone and only a few could actually be found or heard at all. I'd say you would be much more likley to be hit in the eye with bird crap than have something like this taking you out.

It will be up to each individual DZ to decide if this ball will work. Only time will tell.

Kerry

[ramon 0]

If it is Waterfowl shot (which is steel if it is cheap)

It is much less dense and looses its velocity quickly and hunters dislike it.

assuming you want a ball to have a certain weight which requires being packed totally full of 7.5 lead shot (maybe less full for lsmaller shot)

Are you using bismuth shot (expensive, but probably not so for a ball)?


ramon

"Revolution is an abrupt change in the form of misgovernment.", Ambrose Bierce.

[Snowflake 0]

All I can picture is people of my skill level walking through the brush looking for their lost ball and it's cracking me up

[nicknitro71 0]

It sounds to me you guys have solved the problem of home-made-extremely-dangerous balls. If in deed it works as advertised two thumbs up!

Memento Audere Semper

903

[cobaltdan 0]

kerry,

i will pass on the message to stane & robert.

best of luck with vladi's ball, i think it is a great design.

btw. something that we found out when building our spacedarts is that if you get away from a ball shape and go towards more of a bomb or rocket shape. the difference in drag is very significant. with the bomb shape we were using 1/3 the weight typically put into a ball for the same fall speed.

if you like i can email you a 3d autocad file of our space dart shape to experiment with.

sincerely,

dan<><>

Daniel Preston <><>
atairaerodynamics.com (sport)
atairaerospace.com (military)

[mccordia 73]

Wouldn't want to be walking along with my chute when a rain of tiny lead-beads from a missed skyball comes down.
You'll have a couple a hundred nice pinprick holes in your canopy..:)

What would happen if someone would happen to bump the ball hard and it would release somewhere high up..would the lead shoot 'up'?

JC
FlyLikeBrick
I'm an Athlete?

[skymedic 0]

Kerri,

how does it not release the load when you catch it? I understand if you let it go it'll release the load due to atmospheric pressure differences....but what happens when you do catch it...does it still open up in your jump suit pocket?

Marc
otherwise known as Mr.Fallinwoman....

[Spy38W 0]

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Kerri,

how does it not release the load when you catch it? I understand if you let it go it'll release the load due to atmospheric pressure differences....but what happens when you do catch it...does it still open up in your jump suit pocket?

Still opens, but after opening you put a rubberband around it and stuff it into the vladiball sock, or whatever

--
Hook high, flare on time

[Jimbo 0]

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Still opens, but after opening you put a rubberband around it and stuff it into the vladiball sock, or whatever

WHAT?

So now you've got to catch it _and_ worry about putting a rubber band on it, or stuffing into a sock of some sort? I'm certainly no ball master, but that sounds like it might make for a very busy skydive.

-
Jim

"Like" - The modern day comma
Good bye, my friends. You are missed.

[Sonic 0]

Should only add a few seconds after you've deployed.

-----------------------------------
It's like something out of that twilighty show about that zone

[Jimbo 0]

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Should only add a few seconds after you've deployed.

I hadn't considered that whole deployment thing.

So now I'm curious, what set of circumstances is necessary for the ball to deploy? Is it simply altitude? Or is it a combination of altitude and speed?

-
Jim

"Like" - The modern day comma
Good bye, my friends. You are missed.

[Sonic 0]

Just simply altitude. That's why you have to put a bungie round it or put it in a bag etc etc.

-----------------------------------
It's like something out of that twilighty show about that zone

[SurfFlite 0]

Something like this.

Set your audible so that you are catching the ball at 6000-5500 ft.

Catch ball (*maybe a left handed catch)

*Put ball in left hand (if you pull right handed)

Deploy just like you always do.

You are now under canopy floating to earth.(Obviously a parachute malfunction could cause you to drop the ball but at least it is not that tennis ball)

The rubber band that you removed before flight and stowed around 2-3 fingers can now be placed back on the ball to hold it closed.

Put it in your pocket.

Fly your canopy to where ever it is you fly it.

Very easy to accomplish.




The ball has been placed in pockets without the rubberband and some shot can come out (less than a teaspoon full) it depends on how tight the pocket is. If it doesn't have the rubberband around it you have to reach into your pocket carefully and grasp the entire ball to keep it shut as you pull it out of your pocket.

[billvon 2,400]

>The rubber band that you removed before flight and stowed around
> 2-3 fingers can now be placed back on the ball to hold it closed.

So now the sequence would be:

-catch ball
-track away
-deploy
-stick ball under arm
-take rubber band off fingers
-take ball from under arm
-put rubber band around it
-stow somewhere

Seems like a lot to do before you even unstow your brakes. I guess you'd have to open higher to deal with the extra stuff.

I swear, one of these days, between people opening, stowing/removing sliders, dealing with booties, turning off video cameras, stowing skyballs, opening faceplates/removing goggles - we're going to have people that hit the ground before they unstow their brakes. Just too much to do.

[billvon 2,400]

>what if someone on the ground is looking up . . . and gets the shot
> in an eye?

Well, hence the sand suggestion. "But your honor, they got _sand_ in my eye!" just doesn't carry much weight in court.