Fairey D-III Float Plane

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REVAN

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I came across the Fairey D-III while watching a documentary on float planes. What interests me is the float arrangement, as I have considered something similar for my ultralight design. My concern has been that it is different from the traditional pontoon arrangement and I don't know what troubles may lie ahead if I were to pursue it. My interest lies in the ability of this concept to establish a higher AOA for takeoff and landing than is provided by a traditional float. I have a swept-wing design that goes to high AOAs for takeoff and landing and a traditional float may unnecessarily raise the takeoff speed due to limiting the rotation angle. (Note: The Sea-Dart's waterski concept bears some similarities to the D-III's floats.) I have not been able to find any information online that discusses was good and what was bad about this float arrangement on the D-III. I just know that pontoons are more popular, and for obvious reasons.

Does anyone here have any information to pass along regarding how this concept worked (good or bad)? Any opinions on this 3 float arrangement in contrast to the much more common 2 float system?


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dog

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Dec 29, 2019
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I came across the Fairey D-III while watching a documentary on float planes. What interests me is the float arrangement, as I have considered something similar for my ultralight design. My concern has been that it is different from the traditional pontoon arrangement and I don't know what troubles may lie ahead if I were to pursue it. My interest lies in the ability of this concept to establish a higher AOA for takeoff and landing than is provided by a traditional float. I have a swept-wing design that goes to high AOAs for takeoff and landing and a traditional float may unnecessarily raise the takeoff speed due to limiting the rotation angle. (Note: The Sea-Dart's waterski concept bears some similarities to the D-III's floats.) I have not been able to find any information online that discusses was good and what was bad about this float arrangement on the D-III. I just know that pontoons are more popular, and for obvious reasons.

Does anyone here have any information to pass along regarding how this concept worked (good or bad)? Any opinions on this 3 float arrangement in contrast to the much more common 2 float system?


View attachment 128471

View attachment 128472
This has 5 floats
if you want three then go all the way back to
the first flight from water,its a nose floater
 

flitzerpilot

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Hirwaun, Aberdare, S.Wales, UK.
I believe the tip floats simply serve in the same way that protective tip skids are used on several, especially long-winged, biplanes with limited dihedral. It was not uncommon to drag a wing on landing, especially out of wind or in gusty conditions and at sea there is the added problem of choppiness and wave height. Better to have them and not need them.... etc.
 

Dana

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I'm thinking there's a reason nobody makes floatplanes like that any more. Remember, float design is all about reducing water drag so the airplane can accelerate to flying speed as quickly as possible.
 

REVAN

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Dec 6, 2016
Messages
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Location
Tucson, Arizona USA
wiki,Fairey III - Wikipedia
shows that the type evolved into a conventional
float plane,and variants were in service for a long time,so a very good example to look into
Things I've been considering:

For traditional GA type airplanes, the twin pontoon arrangement works better than the three float arrangement of the D-III. That's why we don't see the three float arrangement on floatplanes today. The D-III falls into the category of a traditional airplane. It does not have a high-AOA operating wing. Its straight bi-plane wings have a traditional AOA operating range and the increased AOA range provided by it's three float arrangement didn't provide any real world operating benefits to the airplane.

However, a design that has a high-AOA range up to 20 degrees might tip the scales in favor of using the three float arrangement, if the cons are not too big. No course change has been made on my project as of yet. Twin pontoons are still my plan-A, but after seeing the D-III, I'm giving the three float arrangement a second consideration insofar as I can gather new information on what's historically known about its performance.
 

Riggerrob

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Sep 9, 2014
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2,785
Location
Canada
That 3 - or 5 - float configuration was briefly fashionable during World War One as it could easily be bolted onto an existing tail-dragger airframe.
One advantage of those short floats was that they did not need steps to break surface suction. Again, this was back when they were just starting to understand the theory behind seaplanes.
Even before World War 2, bush-planes standardized on the current twin-float, high-wing configuration (see DHC-2 Beaver or any Cessna on floats). This configuration is the easiest to dock and unload from typical floating docks.
 
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