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Eric Odle
09-04-2009, 10:43 AM
Hello,

Nice to see a dedicated seaplane forum here on Wattflyer! I haven't even gotten my first aircraft and I'm already contemplating the next.

I spend more than half my life surrounded by water on a tugboat in Alaska. The idea of a seaplane is very tempting! However, most of the seaplane videos I've seen are on glassy smooth lake water. I occasionally have those kinds of conditions, but typically the sea surface is at least rippled here.

My question to the experienced hands in this forum is, which seaplane designs are the best sea handlers? Which can handle a bit of wind, and how much? Are there any out there with the ability to self-rescue should they become inverted? Anyone dealt with saltwater corrosion issues?

And if that weren't enough, portability is also a concern. This thing has to go on the plane with me, either checked in baggage or as some sort of carry-on.

I'm not a traditionalist, function and capability are far more important than form in my mind. Speed is pretty cool, too!


Thanks for your suggestions,
Eric

pd1
09-04-2009, 11:08 AM
Hi Eric, Welcome to Wattflyer.
I used to fly full sized sea planes, the Sea Bee was much better in rough water than the Lake Amphibian.
The Sea Bee had a deeper Vee type hull than the Lake.
I suspect for rough water use you would need a deeper Vee hull or deep vee floats.

I don't think anyone make them though. If you look at the size of a model compared to the size of a wave, the wave can be pretty large.

Even full sized planes don't work well in rough water. 30 knot wind in a closed area over a lake or river would only get 6 to 12 inch waves, and we considered that our limit with light planes. When the water had spray, we stopped.

Some of the large multi engine flying boats would survive a rough water landing, open ocean, but few would be able to operate in those conditions for long.

Another factor is water handling, as in taxiing and turning on the water.
When taxiing in the wind, the rudder can get ineffective from when the planes speed is the same as the winds speed while going downwind.
Adding power to turn in those conditions usually aided in flipping the plane over.

So I hate to say this but flying models in salt water will probably be limited to relatively calm conditions.
There are some models that will get off the water quickly, that will minimize the strain on the plane. Some will land pretty slowly, that too will minimize the strain.

There are plans about the internet for a delta wing type plane with the motor mounted up on the tail. This would probably be the best design type for what you want to try.
On RC Groups there's a person called "theKM" he has a good design for this called the "Twinkle". His model is built up from balsa, there are variations made from foam around the net too.
I would lean towards the foam version for your purpose.

Here's one here that might work for you.

http://www.wattflyer.com/forums/showthread.php?t=41896

You'll have to experiment with how much waves or wind is too much though.

Good luck with your quest.

Paul

CHELLIE
09-04-2009, 11:23 AM
Hello,

Nice to see a dedicated seaplane forum here on Wattflyer! I haven't even gotten my first aircraft and I'm already contemplating the next.

I spend more than half my life surrounded by water on a tugboat in Alaska. The idea of a seaplane is very tempting! However, most of the seaplane videos I've seen are on glassy smooth lake water. I occasionally have those kinds of conditions, but typically the sea surface is at least rippled here.

My question to the experienced hands in this forum is, which seaplane designs are the best sea handlers? Which can handle a bit of wind, and how much? Are there any out there with the ability to self-rescue should they become inverted? Anyone dealt with saltwater corrosion issues?

And if that weren't enough, portability is also a concern. This thing has to go on the plane with me, either checked in baggage or as some sort of carry-on.

I'm not a traditionalist, function and capability are far more important than form in my mind. Speed is pretty cool, too!


Thanks for your suggestions,
Eric
Wow, Thats a Tall order :D IMHO you will need a sea Plane, and a rescue Boat with another Radio, once the plane is inverted in Water, you will not have any control over the plane to bring it back in, the electronics will have to be sealed, the motor will have to be flushed with fresh water if your in salt water, and sprayed down with WD 40 , Larry 3215 has suggested a product called Corossion X I think it is to seal some of the electronics, and put it in the Luggage, Hmmmmmmm, you would have build the plane or modify it so it will come apart, and can be screwed together with nylon screws, Here is what I would use, there might be better, but I kind of think this might be more stable, and less chance of tipping over, with only one Fuselage/sponson in the middle, Take care, Chellie

http://www.parkflyers.com/html/hybrid-air.html

http://www.parkflyers.com/assets/images/hybrid-takeoff.jpg

nascarwings
09-05-2009, 02:55 AM
This is all ya need....flys well in wind...easy to fly..The Multiplex Mentor on floats...108590...any questions let,em fly..:)

Eric Odle
09-05-2009, 09:14 AM
Thanks for your comments! I thought it was worth asking the question, even though those requirements are pretty steep. Just like any boat, you have to make some serious compromises and are bound to be disappointed if you want it all.

I'll break this down a little. Know any flyers who regularly deal with salt water issues? From what I can tell most of this stuff is on the fresh water, and not particularly well sealed.

-Eric

CHELLIE
09-05-2009, 09:42 AM
Thanks for your comments! I thought it was worth asking the question, even though those requirements are pretty steep. Just like any boat, you have to make some serious compromises and are bound to be disappointed if you want it all.

I'll break this down a little. Know any flyers who regularly deal with salt water issues? From what I can tell most of this stuff is on the fresh water, and not particularly well sealed.

-Eric

Hi Eric, contact member PHupper or Larry3215 for the best info on sealing electronics for salt water use, hope that helps, Chellie

http://www.wattflyer.com/forums/showthread.php?t=41051&highlight=sea+plane

nascarwings
09-05-2009, 01:08 PM
I have ...fresh water in my front yard and salt water in the back...lol...and salt water is tough on the gear...the elec..stuff is easy just use http://www.corrosionx.com/ the worst thing is the servos!!!!.. just seal them up the best u can...also any thing the is steel replace it with brass or plastic...tend to go with a plane with hi mount motor... http://www.rcgroups.com/forums/showthread.php?t=922465
less prop wash but imho they are harder to fly....also stay with a foam type plane ... keep posting and we will get ya in the air in no time...:Q

Larry3215
09-05-2009, 06:02 PM
Avoid salt water. Thats all you need to know :)

Seriously, its bad news. Nothing you do - CorrosionX is the best bet but still wont cut it - will protect your motor, electronics or batteries well enough to survive over any length of time. No matter how well you try to seal things up - the salt water WILL GET INSIDE.

You're bearings will go first in the motors along with the stator material and then the aluminum parts - even if they are treated with CorrosionX.

You work on boats so you're familiar with galvanic corrosion. Thats what happens when ever you have two different metals in salt water. Its what destroys outboard motor parts and props in just days if you dont have zincs properly installed on them.

Well, there is no way to do zincs on our planes - especially inside the motors.

The next big issue is the batteries. They have aluminum tabs on the + side and steel on the negative side and copper soldered to both - all different metals and no where to attach a zinc. You get the same galvanic corrosion on them when salt water gets inside them. The positive tabs will erode away in just a few minutes in salt water.

The rx and esc's can be treated with CorrosionX or, better yet, dipped in conformal epoxy coatings but you cant do the servos and motor that way.

Fly off fresh water. You still need to use CorrosionX to protect the electronics and motor etc from damage but it will have a chance to work in fresh water.

Salt water will just cost you money :)

Larry3215
09-05-2009, 06:04 PM
Oh - I agree with pd1 on the rough water.

A 2 foot tall wave is to one of our planes what a 50 foot tall wave is to your tug boat :)

Trying to land or take off on even 6" tall waves would be like trying to run a speed boat through 10 foot tall breakers at full throttle :eek:

Eric Odle
09-06-2009, 09:42 AM
Ah, well, guess I better stick to dry land for the time being! Thanks for weighing in Larry, I've been working my way through your massive Capricorn thread. The near 3D flying I'm seeing from those craft made me wonder if the scale argument didn't apply when it came to flying off the water. It's not surprising I guess that electronics and saltwater don't get along.

Thanks folks for grounding my expectations... Though it's more like getting doused by a bucket of cold seawater!

Larry3215
09-06-2009, 06:32 PM
You're right about the Capricorns and their ability to handle rough water landings and take offs - with a couple of big 'BUT's' tacked on :D

The Capricorns are a different breed of 'Seaplane' as far as how they fly so the normal flight rules and the normal water handling rules dont apply quite the same way to them.

The key is the incredibly LOW wing loading.

A normal sized Capricorn thats built light has a wing loading that lower than ANY other foamy out there - especially one that large. Nothing else comes even close. My standard size Cap has a wing loading of about 2.5 ounces/ft.

A Tensor 4D is over 3oz/ft at the lightest. Even the newest indoor parkzone Vapors etc are higher wing loading than a lightly built Capricorn.

That low wing loading means it will fly sloooooooowly. Much slower "on the wing" than most any other plane. That in turn allows for very short, almost instant take off runs and nearly vertical landings in even the softest breezes.

So - in rough water, you can take off a Capricorn on the back of a wave and land on one with no worries of having to plow through the water and getting beaten to pieces.

The down side to that rough water capability is that the super low wing loading also makes it far more susceptible to the wind. Lightly loaded Capricorns get blown around a lot more than a heavier plane will be.

Generally, when ever you have rough water you also have wind - thats where the rough water came from normally :)

Your going to have to be a very good pilot to handle a Capricorn in hi winds. I'll brag a bit here and say that I happen to enjoy doing just that ;)

I'll fly my Mega Capricorn in winds that ground my other planes - but I have to be extremely careful of cross winds or it gets blown over.

Salt water is still a no-no though :)