Safety of outboard floats on seaplanes?

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yankeeclipper

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I see that this site has several planes that include floats that are located at the outer extremes of the wings. I'd have thought that this could spell disaster if a wing tip dropped unexpectedly, and at an inopportune time.
 

orion

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Assuming a properly designed tip float, dipping it into the water, even in flight, should pose no problem since the "hull" of the float is generally designed for planing conditions. As such, when the float touches the water it just simply skips across the surface rather than catching it. The loads at that condition tend to be relatively light so even a relatively hard contact will not result in any adverse damage or directional control problem.
 

yankeeclipper

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I see. So then, what's the disadvantage to these? Seems that being that far out, one could design a much smaller float, and possibly integrate it into a wing fence.

Thanks for the answer.
 

orion

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The major disadvantage are drag (design dependent) and maneuvering near or about a dock.

The primary advantage is stability while floating or at low speed - something that a hull alone has a difficult time providing, especially if you have a high mounted mass as in the case of some pylon mounted engines. Yes, some hulls do have the capability to provide the static case stability however the side extensions that requires become just a lot of unnecessary wetted area in flight.
 

litespeed

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You could even do a float that folds up in flight to become the wing tip, just like a Catalina.
 

yankeeclipper

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Or the Trident Trigull.

Good point about the Dock. Good points all around, as usual. I only ask because, well, google my username and "wing tip"--that's why.

Thanks for the, uh...tips.
 

Riggerrob

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You could even do a float that folds up in flight to become the wing tip, just like a Catalina.
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Similarly, some Grumman Geese were retrofitted with retractable wing tip floats (ala. Catalina). Retractable floats allowed them to retract one float to avoid denting docks ..... knocking over dock hands ...... you get the picture.

OP If you look closely at tip floats, you will notice that many are set at a steeper angle of attack than the main hull. This nose-high attitude means that they generate lots of lift .... fighting moment ..... wing-levelling ..... if they dip a tip float at any more than walking speed.
 

Aesquire

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The big Martin "Clippers" used sponsons on the hull to stabilize the planes in the water. Put a lot of design work into them to also get some lift along with the unavoidable drag, made them big fuel tanks, etc. Docking was a major consideration. Passengers prefer a short, stable ramp to the dock.

Compromises. The heart of design choices.
 

jedi

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I see that this site has several planes that include floats that are located at the outer extremes of the wings. I'd have thought that this could spell disaster if a wing tip dropped unexpectedly, and at an inopportune time.
The wing mounted floats are designed to break away before disaster strikes. Then the trick then is to keep the opposite float in the water to avoid a roll over into the floatless wing.
 

TFF

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James Bond did just fine in "Man with the Golden Gun" with his Seabee. Botch any landing on water and you will wish you were on land.
 
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