Sectional Charts

Next to an obstacle, a sectional shows two numbers such as 1,549 and (587). The number in parentheses is:

Answer

The height above ground level (AGL)

The top number is the obstacle's top MSL; the number in parentheses is its height above ground level (AGL).

Source: FAA Chart User's Guide

Not the answer

  • The obstacle's light color
  • A frequency
  • The height above mean sea level (MSL)

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