Definition
On a seaplane float or flying boat hull, the distance measured from the bow (front tip) back to the step — the deliberate break in the underside of the hull or float where the planing surface ends.
Plain English
It is the length of the front part of a seaplane float, from the very front of the float back to the notch on its underside.
Context Anchor
Seen in seaplane float and hull descriptions, especially when discussing how the aircraft rides on the water and gets onto the step for takeoff.
Derivation
‘Forebody’ comes from ‘fore’ (front) and ‘body’ — literally the front part of the body of the float. Naval architects used the same term for ships long before seaplanes existed, and it carried over directly.
Why Pilots Care
Forebody length affects how a seaplane behaves on the water during takeoff — particularly how it rides through waves and transitions onto the step. Pilots flying floatplanes benefit from understanding the geometry that shapes their water handling.
Intuition Check
Do not read this as the length of the whole aircraft nose. In this context, it means the front water-contacting part of a seaplane float or hull, measured only to the step.
Example Sentence 1
The float's forebody length determines how much of the hull contacts the water before the seaplane rises onto the step.
Example Sentence 2
Longer forebody length shifted the aerodynamic center forward on the test aircraft.