Mean sea level

Definitions

• The average height of the surface of the sea at a particular location for all stages of the tide over a 19-year period.
• The average height of the surface of the sea for all stages of tide. A number preceding MSL indicates altitude in feet above mean sea level.

References

• Instrument Flying Handbook, Federal Aviation Administration, 2014
• Pilot's Handbook of Aeronautical Knowledge, Federal Aviation Administration, 2023
• Weight-Shift Control Aircraft Flying Handbook, Federal Aviation Administration, 2008