Piet Flotation, hehe!!!

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KenBickers
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Piet Flotation, hehe!!!

Post by KenBickers »

Okay, folks, it's been way too long since the BPA website was returned to functionality for an interesting building discussion. So here's an oldie but a goodie (and if you remember this, you're exposing just how old you've become).

Here's what I'm wondering (hehehe): How many ping pong balls should I add to my Piet to keep it afloat after an inadvertant water ditching? I'm thinking I'd basically need to fill the wings with them, but also probably a bunch in the forward cockpit to keep it more or less level. How many? Where?

Somebody say something. The silence is deafening.

Cheers, Ken
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taildrags
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Re: Piet Flotation, hehe!!!

Post by taildrags »

If I remember correctly, it was Corky Corbett who raised that interesting design question. Since I now own his plane and have actually flown it over water on various occasions, I should probably have investigated the answer more closely but I really can't remember! I'll have to consult with Professor Archimedes and sit down with the abacus one of these evenings. And looking in the Aircraft Spruce catalog for FAA PMA ping pong balls in the "float plane" section of their catalog, I see that I can buy 100 of them for $20 so let's see what it might cost me to convert 41CC to a "float plane" :D

-Oscar
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KenBickers
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Re: Piet Flotation, hehe!!!

Post by KenBickers »

Oscar,

It's great to get an engineer with an abacus on this important question.

I'm wondering if there should be a mix of different size balls to add bouyancy where otherwise water would be. I've tentatively ruled out pickleballs for this, though perhaps there's a good way to plug the little holes in them. Maybe someone will have a good suggestion. :ugeek:

Cheers, Ken
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taildrags
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Re: Piet Flotation, hehe!!!

Post by taildrags »

Ken, it's going to be hard to beat ping-pong balls for lightness of weight and ability to fit into smallish voids. I would steer clear of anything heavier or larger. Now, if you want to we could explore the idea of helium balloons because they could be inflated to conform pretty closely to the shape of the cavity that they're in, and the helium might help with climb capability and extending the glide during non-water operations. Just avoid areas where there might be nail points or wood splinters inside the cavities to be filled.

-Oscar
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KenBickers
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Re: Piet Flotation, hehe!!!

Post by KenBickers »

Oscar,

I'm liking the idea of helium bladders, especially to gain better climb and glide range. I'm worried, though, that material tough enough to deal with potential abrasion and sharp edges inside the wing might undue some of the benefits of helium. Perhaps we should think about hydrogen. Much lighter. Besides, what could go wrong? :twisted:

Cheers, Ken
Alpo
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Re: Piet Flotation, hehe!!!

Post by Alpo »

I hate to switch gears too much from the gold standard of faa/pma ping pong balls and hydrogen bladders. What about a belly pod inflatable dinghy? Seems only logical to make it amphibious. Water landing, no problem, pull this cord.
Alex Wyatt
Prairie Grove, AR
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KenBickers
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Re: Piet Flotation, hehe!!!

Post by KenBickers »

Ahoy Alex,

Belly pod inflatable sounds like a post holiday meal condition. But I like your way of thinking.

The challenge (let's assume there's only one, really let's) might be to keep the Piet from being too tippy laterally. It might need deployable floation outriggers.

I'm thinking an alternative would be to size the main tires and tailwheel to have sufficient volume that a Piet could waterski on the surface and continue to stay afloat on its landing gear, even as it slows below speeds required to waterski.

Perhaps Oscar with his portable abacus can run calculations for how large the tires would need to be, perhaps with options of normal air, helium, or hydrogen to inflate them. I would assume they'd mostly be used on freshwater, which would mean they'd need to be somewhat larger than if operated exclusively on saltwater.

Cheers, Ken
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taildrags
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Re: Piet Flotation, hehe!!!

Post by taildrags »

Fellows, I apologize for appearing to stall for time here, but I really can't plug in the abacus and boot it up until I know if we're trying to figure out whether to float the Piet on salt water, or on fresh. The density is different. I also want to know the gross weight of the Air Camper on which to run the calculations.

-Oscar
LarryM
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Re: Piet Flotation, hehe!!!

Post by LarryM »

Does anyone know how to waterproof a pickleball?
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taildrags
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Re: Piet Flotation, hehe!!!

Post by taildrags »

Larry, I would say that it depends on how long you want the pickleball to remain watertight. Cheap, quick, and easy would be to wrap it with packing tape or duct tape, but over time it may leak as the tape adhesive ages.

-Oscar
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KenBickers
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Re: Piet Flotation, hehe!!!

Post by KenBickers »

I'm thinking one of those freezer bag vacuum sealers that they sell late at night on cable tv might work. One pickle ball, one freezer bag, zzzz, sealed, done, next. It should keep the air inside fresh forever, freezer proof, too.
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taildrags
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Re: Piet Flotation, hehe!!!

Post by taildrags »

I may not live long enough to encapsulate that many pickleballs.

-Oscar
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