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Explosive Decompression! - No puncture.

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tautologies
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Re: Explosive Decompression! - No puncture.

Postby tautologies » Tue Jun 18, 2019 6:43 pm

edt wrote:
Tue Jun 18, 2019 6:36 pm
yeah but if a valve is loose it doesn't let all the air out in seconds, takes at least 1 or 2 minutes. If it all comes out in 30 seconds it's usually a plug coming loose. I still think it's really weird and might be something nobody has thought of yet. I would try to reproduce it.

It could also be a hole in the bladder where it is folded or double. It would give the same symptoms, except it would not be that explosive decompression at the end.

Im just going by what I got out of the description. Seems something isn't quite air proof, and when it gets wiggled, the air gets a path out. If it is explosive, then I do not think it is a pinhole. Then I think the most probable solution is a loose valve. With high air pressure in the bladder, the valve attachment gets pinched onto the LE dacron, and then keeps tight until something releases that pressure...a turn. I can definitely be wrong, but this is the path I would take to explore what is going on. :-)
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gilesb
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Re: Explosive Decompression! - No puncture.

Postby gilesb » Tue Jun 18, 2019 6:59 pm

I had an issue with an old kite, was solid on the beach (even if left for a while) and when first in the air but lost loads of air quickly when flown. Once back on the ground after the aborted session, I noticed that the tubes and connections on the one pump had started to perish. On the beach when the tubes and kite had no tension the holes closed up. If I twisted the kite to simulate a turn/being in the air I could see the holes opening up and loads of air being dumped out. IRRC the worst problems were with the PU connections for the one pump tubes, plenty of posts regarding this material becoming less flexible with age and valves cracking. In the end, all my PU connections were on their way out and it was time for a new kite (was nearly 10 years old).

I know your kite is new, but maybe some hard plastic has prematurely aged in this area, poorly manufactured or they have not been stuck to the bladders incorrectly. Also possible that the rubber tubes are little short and putting tension on the connections making a leak in this area worse. Everything is looser on the beach with the kite faced into the wind, you need to see how the one pumps behave once tension in the canopy or struts put in a position to simulate tension in the canopy. It is tricky to do on the beach but you can pull the struts up and inspect the one pump system. If you can do indoors in a quiet room you might be able to hear the leak more easily when you manipulate the kite, however, given your description you should hear easily if you get the offending part into the correct position outside.
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Re: Explosive Decompression! - No puncture.

Postby Beardytello » Wed Jun 19, 2019 9:18 am

Thanks chaps, lots of things to investigate seemingly!

I just want to go kiting lol, I need to be rich, or sponsored!

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Re: Explosive Decompression! - No puncture.

Postby Flyboy » Wed Jun 19, 2019 2:40 pm

Beardytello wrote:
Wed Jun 19, 2019 9:18 am
Thanks chaps, lots of things to investigate seemingly!

I just want to go kiting lol, I need to be rich, or sponsored!
I would suspect the Max Flow valve. The valve flaps need to be properly seated or they can leak air. It happened to me on a number of occasions - in my experiences it didn't happen that suddenly, but it is possible. Then you pump up another time & there's no apparent problem.

Air suddenly going into an empty strut would not have sufficient volume to collapse the LE.
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Re: Explosive Decompression! - No puncture.

Postby kite_hh » Wed Jun 19, 2019 5:49 pm

Flyboy wrote:
Wed Jun 19, 2019 2:40 pm

Air suddenly going into an empty strut would not have sufficient volume to collapse the LE.
Maybe I missed something, but a collapsing kite isn't what I had in mind, nor did I read anything alike by OP.

When I started paying more and more attention to the details of kite inflation, I was astonished of the ratio between the strokes that are needed to get the kite tubes to look filled and the (many) additional strokes on the pump needed to get it to the desired pressure. Hence, a lately inflated strut can take away quite some pressure off the whole system. So yes, the kite is still inflated, but it surely isn't on that pressured level where you would like it to be and hence can react unwanted.

To be fair one would usually notice a strut not being filled, so it may no be likely, but then again people miss the weirdest thing before going on the water, so.. :-)

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Re: Explosive Decompression! - No puncture.

Postby Flyboy » Wed Jun 19, 2019 5:57 pm

kite_hh wrote:
Wed Jun 19, 2019 5:49 pm
Flyboy wrote:
Wed Jun 19, 2019 2:40 pm

Air suddenly going into an empty strut would not have sufficient volume to collapse the LE.
Maybe I missed something, but a collapsing kite isn't what I had in mind, nor did I read anything alike by OP.
Beardytello wrote:
Tue Jun 18, 2019 9:09 am


in the middle of a turn my kite just completely crumpled and dropped out of the sky, its a newish Blade, only been used about 7 or 8 times.
I have often failed to pump a strut by initially failing to release the strut valve. Releasing the valve allows air to flow into the strut. It does have an effect on reducing the pressure in the LE, but not to the extent that the kite would not fly properly.

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Re: Explosive Decompression! - No puncture.

Postby kite_hh » Wed Jun 19, 2019 10:23 pm

Ok. Fair enough. :thumb:
I never tested it, but only realized it could take quite some pressure off the whole system.


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