What makes a landing good?

• The rule: it is a failure if the head of the javelin "in contacting the ground when it first lands touches the sector line or the ground outside the sector line".
• Head first: "A throw shall be valid only if the metal head strikes the ground before any other part of the javelin."
• Some angle is enough: the commentary says there must be "some angle on landing, however small". Flat and tail-first landings are red flagged.
• The sector: two white lines 50 mm wide. Their inner edges run through the points where the arc meets the runway lines and would meet at the centre of the arc's circle, 8 m behind it. The angle is 28.96 degrees.
• Each line is out: the inner edge of each sector line is the boundary. A landing that touches the line is a failure.
• First landing only: the rule looks at where the head first meets the ground. A bounce, roll or slide afterwards is not judged.
• Hitting something on the way: since 2026 it is also a failure if the javelin, or any part of it, touches any object outside the sector line after release and before it lands.
• The ground: grass, cinders or another surface on which the implement leaves a mark.
• The signal: a judge near the landing shows a throw that is out of the sector by holding an arm out. A different signal is recommended for a javelin that did not land head first.

The sector is where the judges stand ready and nobody else is allowed, so a throw outside it is a danger as well as a miss. Counting the line as out gives one clear test: the mark is either wholly inside or it is not. The head-first rule exists because a javelin that lands flat leaves no single mark to measure from and can skid a long way.