SkyDrill

Purpose of a leader line

Aviation Mechanic General (AMG) practice question 8 of 15 on Aircraft Drawings. ACS element AM.I.B.K1 · difficulty: standard. Want to answer it in a timed quiz? Use the Aviation Mechanic General (AMG) practice mode.

Question bank updated 2026-09-22

QUESTIONA note on a drawing is connected to a fitting by a solid line that ends in a single arrowhead at the fitting. What does that line tell the mechanic?

  1. AThe note applies to that fitting
  2. BA measurement begins or ends at that point on the fitting
  3. CPart of the fitting has been left out of the drawing
Show the answer and explanation

Correct answer: A. The note applies to that fitting

  • A — correct A solid line with one arrowhead is a leader line, which indicates the part or portion that a note, number, or other reference applies to.
  • B — incorrect Origin and termination of a measurement are shown by a dimension line, which has opposite-pointing arrowheads at each end, not a single arrowhead.
  • C — incorrect A portion not shown on the drawing is indicated by a break line, drawn freehand for short breaks or as a ruled line with zigzags for long breaks.

BACKGROUND

Leader lines are solid lines with one arrowhead. They point from a note, part number, or other reference to the part or portion of the object that the reference applies to. The handbook also explains that when a note refers to a specific part, a light line with an arrowhead leads from the note to the part. Dimension lines differ because they carry arrowheads at both ends and are broken at the midpoint for the measurement. Break lines, by contrast, show that part of the object is omitted.

STUDY TIP

Count the arrowheads: one arrowhead is a leader pointing to what a note applies to; two opposite arrowheads mark a dimension.

KEY POINTS

  • A leader line is a solid line with one arrowhead.
  • It indicates the part that a note, number, or reference applies to.
  • Dimension lines have arrowheads at both ends; break lines show omitted portions.

SOURCES

  • FAA-H-8083-30B ch04 "Leader Lines"
  • FAA-H-8083-30B ch04 "Notes"
  • FAA-H-8083-30B ch04 "Dimension Lines"
  • FAA-H-8083-30B ch04 "Break Lines"
Practice the Aviation Mechanic General (AMG) test →Timed 60-question exam, by ACS area, or review your misses. Free.
MORE ON AIRCRAFT DRAWINGS

SkyDrill is not affiliated with the FAA. This is an original practice item based on FAA-H-8083-30B Aviation Maintenance Technician Handbook – General, 14 CFR part 43 and part 65. Regulations and handbooks are revised; confirm details against the current edition.