Definition
True north is the direction along Earth's surface toward the geographic North Pole — the fixed point where Earth's axis of rotation meets the surface in the northern hemisphere. It is the reference direction used on aeronautical charts, where the lines of longitude (meridians) all converge at this point. True north is distinct from magnetic north, which is the direction a compass points and which lies in a different location that shifts over time.
Plain English
True north is the direction toward the actual top of the Earth — the spot the planet spins around. It is the north used on charts, and it does not move. It is not the same as the north a compass shows.
Context Anchor
Seen in navigation and magnetic variation discussions, especially when converting a chart direction into a compass direction to fly.
Derivation
True' here means 'genuine' or 'fixed' — the real, geographic north — as opposed to the compass version which varies. Calling it 'true' distinguishes it from magnetic north, which depends on Earth's magnetic field and drifts over time.
Why Pilots Care
Pilots use true north as the reference for plotting courses on charts before converting to magnetic headings for the compass.
Grounding Statement
Picture the Earth spinning like a top — true north is the point at the very top of the spin, where the axis comes out of the ground.
Intuition Check
True north does not mean “the north shown by the compass.” Here, “true” means referenced to the geographic North Pole, before magnetic correction is applied.
Example Sentence 1
The course line drawn on the sectional chart was measured relative to true north.
Example Sentence 2
Before applying magnetic variation, the flight plan was drawn with all headings measured from true north.