Pitch
Pitch is rotation around the boat’s side-to-side axis. Positive pitch generally describes a bow-up attitude and negative pitch a bow-down attitude, depending on the sensor convention. On a planing boat, pitch changes during acceleration, transition onto plane, trim changes, wave encounters and load shifts.
Roll
Roll is rotation around the boat’s fore-and-aft axis. It can reflect uneven loading, wind, steering input, wave action or control-surface changes. A single roll number does not diagnose a problem; its timing, magnitude and relationship to other data matter.
Why time alignment matters
Motion becomes much more useful when synchronized to speed, GPS position, engine RPM and control inputs. If pitch rises at the same moment speed increases and trim changes, that sequence tells a different story than a pitch change caused by a wave. This is why data logging needs a shared timeline rather than separate screenshots from multiple gauges.
Attitude is context, not a target
There is no universal ideal pitch or roll angle for every hull. Different boats are designed to run differently, and the best attitude can change with speed and load. SmartTrim uses attitude as part of a vessel state rather than treating a single angle as the objective.