Definition
A maneuver used to put a seaplane on the step (the planing portion of the float or hull) during the takeoff run, or to maintain the seaplane on the step while turning on the water.
Plain English
A turn made by a seaplane while it is skimming on the surface of the water at high speed, before it lifts off. The pilot uses it either to get the seaplane up onto its planing surface or to change direction without slowing back down.
Context Anchor
Used in air traffic control and radar-vectoring discussions when an aircraft is guided through heading changes in smaller steps.
Derivation
The 'step' refers to a notch or break in the bottom of a seaplane float or hull. Once the seaplane is moving fast enough, water flow separates cleanly at this step and the seaplane planes on top of the water rather than plowing through it. A 'step turn' is therefore a turn made while in this planing condition.
Why Pilots Care
Enables quicker heading changes on water with less resistance and better control compared to displacement taxiing.
Analogy
Similar to a boat turning while up on plane instead of slowly plowing through waves.
Intuition Check
Do not confuse a step turn with a steep turn. In this term, “step” means the turn is broken into stages, not that the bank angle is steep.
Example Sentence 1
After lifting onto the step, the pilot performed a gentle step turn to align with the takeoff path along the lake.
Example Sentence 2
In crosswind conditions on the lake, a step turn helped maintain directional control during the initial acceleration.