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Vladiball goes belly

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We have come up with a good belly speed configuration for the Vladiball. Several of our customers have tested it out and are very happy with the results. There are even instructors who are using the Vladiball with students, that's right I said students. According to them it is a fantastic training tool.
Below is an email I received from a customer in Ireland describing his findings. along with an attached jpg.

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We made a number of successful Vladiball jumps this weekend and we had
some great fun!

In total we made 8 jumps with the ball and we retrieved it every time.

I filled the ball exactly as you said: fill one half completely with lead
shot (I used lead shot, about <2mm in diameter) using the shorter of
the two tail lengths you gave me (about 6-7 inches). The ball weighed about
350g (although it was difficult to get a very accurate measurement since the
scales were very sensitive to the position of the ball on the scales).

Initially, when we released the ball and tried to catch it again, we
noiticed it would tend to fly away from you when you went up to it to grab
it. Particularly if there were 2 or more approaching the ball. The
perculiar thing was that the ball would fly "up" and then pop down
elsewhere. (This makes for a very funny video). We feel this may be due to
the deflected airflow coming off the jumper. The air would be deflected to a
much greater extend than it would with freefliers because of the amount of
their body exposed to the air.

However, we soon learned a way of catching the ball without it getting
away - we would fly up and quickly grab it with 2 hands.

On the next jump we took the ball up and released it immediately after
exit and just sat back and watched it. It seemed to float slightly after
exit but this could be due to the ball reaching terminal velocity at a
different rate to the jumper because it was fine later. It is very stable in
flight (i.e. the fall rate is constant, and it does not move around) when
you are not too close to it, however, it does have a "wobble" (i.e. it
bounces around and oscillates on the one spot) but does not move anywhere.
We were very happy with the ball at this stage but felt it the fall rate
could be increased slightly.

We filled it up with a small bit more of lead shot (still about half fill
the ball but with a slight mound) and it now weighed just under 400g
(approximately). This is now the perfect weight. (A total of 12 people of
different sizes and different skill levels jumped with the ball over the
weekend and nobody had any trouble staying with it.)

We then started to throw the ball to each other in freefall. This was when
the real fun started. We found it to be very solid and robust. It is very
easy to throw and to catch (even with one hand). We tried throwing it softly
and it would gently sail across the sky. We also threw it a bit harder and
it still goes straight across the sky but a good bit faster. It seemed that
sometimes the fall rate changed during the throw but this could be due to
either (i) the jumper holding the ball was not falling at the ball's fall
rate before the throw, (ii) the weight inside moved around on the throw and
caused it to float/sink slightly, or maybe another reason.

I wonder if the characteristics of the ball would be different if it was
full inside (i.e. no empty space - but still the same weight). Since I have
not seen the ball at freefly speeds it is difficult for me to compare the
stability, however, I was very impressed with how solid the ball was.


There is much excitement at our dropzone over the vladiball.

Please email me if you would like to discuss any aspect of the vladiball
for FS jumping. I think that it is fine for FS.



We are still working on the freefly ball. It appears that all the really good freeflyers have no problem with the ball but some lesser skilled do. We are diligently working on making this thing user friendly for everyone. We do have a tail configuration that works great and makes the ball fly perfectly straight but it is too fast (~185mph) When we decrease the weight in the ball using this same tail it begins to wobble. We are getting close to solving this and should have something that will work for everyone in the coming months.
Kerry

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been using one at the dz i jump at here in utah for a while now... belly and freeflying.... since there arn't that many experianced people at freeflying we use it alot for belly.. just this past weekend we tried to build a round around the ball with decent reults...... we are going to be ordering a few in the near future to use as trining aids in flarate and such....

______________________________________
"i have no reader's digest version"

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Any object in freefall is banned at Peterlee (where me and jumpmunki jump) because our DZ is in the middle of factories, residential areas, numerous open roads (including main goods routes), and a couple of school fields.

Nick
---------------------------
"I've pierced my foot on a spike!!!"

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When I was in Utah last summer I made a belly jump with the one Wingnut was talking about. it was fun.

I m not the expert and this description comes from about 5 min looking at the ball. The ball on the ground has a rubberband around it since it is not "locked" and the shot would fall out since it would open. Inside there is a bladder that you equalize the pressure to the ground pressure and it has a locking pin attached.. The ball is two 1/2's hinged on one side. When closed the pin that is attached to the bladder locks the ball shut as the elevation goes higher. Basically the bladder expands and pushes the pin to lock the two halves as a ball. The idea is really simple, but very cool. If you dont catch the ball as you fall the bladder shrinks as air pressure increases durring the decent and pulls the pin below a calibrated altitude. Ball opens up, shot spreads out and is harmless, ball flutters down to a safe landing somewhere. If you catch it, open up above the release altitude and put it in a bag or put a rubberband on it to not lose the shot. The pin is going to unlock below a certian altitude.

Hope that description helps Wally....

Scott C.
"He who Hesitates Shall Inherit the Earth!"

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Thats cool as hell. I had one go on its side at eloy......:S (but we got it, no worries ;))

I still haven't jumped mine yet, dunno quite how to load it for freefly. :P

Wrong Way
D #27371 Mal Manera Rodriguez Cajun Chicken Ø Hellfish #451
The wiser wolf prevails.

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Any object in freefall is banned at Peterlee (where me and jumpmunki jump) because our DZ is in the middle of factories, residential areas, numerous open roads (including main goods routes), and a couple of school fields.



Yeah i remember. Was down there for the BCPA thing. Brilliant laugh. You guys coming up for the scots 7-9th of may?

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Initially, when we released the ball and tried to catch it again, we
noiticed it would tend to fly away from you when you went up to it to grab
it. Particularly if there were 2 or more approaching the ball. The
perculiar thing was that the ball would fly "up" and then pop down
elsewhere. (This makes for a very funny video). We feel this may be due to
the deflected airflow coming off the jumper. The air would be deflected to a
much greater extend than it would with freefliers because of the amount of
their body exposed to the air.
.



A perfect example of interference drag - the main reason RW formations slow down as they get bigger. Some organizers are convinced that the reason is that jumpers stop flying when they dock (well, maybe some do) but the laws of physics ARE the laws of physics. Two objects close together have MORE drag than the sum of the drag of each of them separately.
...

The only sure way to survive a canopy collision is not to have one.

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How are they banned in the uk its not in the ops manual?



If memory serves, isn't it a CAA regulation, rather than a BPA one?

Somthing about no object being released into freefall without an attached parachute device unless it's an emergency?

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