Floatplanes distance conversions?

[skyloone]

Hi

I know little of floatplane flying but am interested to know how one calculates take off & landing distances. I assume each a/c has conversion tables etc.. but is there a rough rule of thumb for various water conditions. If there is a publication I should look at, I'd be interested.

Thanks

[werbil]

The POH usually specifies smooth, non glassy water for performance calculations.

I am not aware of any published factors for the various water conditions - and I don't believe there can be because the effect on performance between various water conditions varies dramatically between types. Even on the same type, there is no fixed relationship between the different water conditions - the relationship varies depending on the weight, the position of the center of gravity and the wind vector in addition to the water conditions.

Judging the effect of the water conditions on takeoff performance comes with experience, however it is more an art than a science. Seaplane pilots often refer to take off times rather than take off distances when comparing take off performance as it is far easier to measure. When operating in restricted areas, picking suitable abort points is critical - I believe statistically for non-amphibious seaplanes the most common accident is CFIT into terrain after take off.