Minimum Safe Altitude (MSA)
MSA is calculated by taking the Maximum Elevation Figure (MEF) from the sectional
chart grid that corresponds to your current position. In areas below 3,000 feet, 1,000 feet
is added. In areas above 3,000 feet, 2,000 feet is added. In the example below, the current
aircraft would be considered to be at 7,000 feet. If you are within 5 nm of another grid
with a higher MEF, the higher MEF will be used. The MEF on the sectional chart is
derived by taking the altitude of the highest obstruction within the grid, rounded up to the
next 100 feet, and adding 300 feet. For example, if the highest obstruction is 4,728 feet,
the MEF would show as 5,100 feet.
eta aSLE 01:23
MinSafeA 7200’
EnrtSafeA 16800’
Minimum En Route Safe Altitude (MESA)
Minimum En Route Safe Altitude is the highest MSA for every point between the aircraft
present position and the “TO” waypoint with a 5 nm buffer around the course. The value
will be replaced with dashes if there is no valid GPS position, the TO waypoint is blank,
or the current position is outside of the database coverage area. In the example shown
above, the MESA for the present position of the aircraft would be 16,800 ft. The
mountainous terrain would add a 2,000 ft. buffer to the 14,800 ft. Maximum Elevation
figure indicated from the sectional chart.
Flight Time
Flight Time shows the elapsed time in hours and minutes (00:00 to 99:59) from departure.
If the Flight Timer is not started the value will be replaced with dashes. The Flight Timer
Trigger options are set in the System Functions.
FT00:07
Navigation Basics
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