All UK VFR Charts have grid MEF (Maximum Elevation Figures) printed. These, as (with one correction)
Backpacker says, are the:
- Altitude of the highest obstacle in the grid, rounded up to the nearest 100'.
- Altitude of the highest terrain in the grid, plus 299' to account for an unknown obstacle, rounded up
to the nearest 100'. (There is no notification requirement for obstacles up to 300'; that's why we
add 299' if we use the highest terrain figure.)
MSA (Minimum Safe Altitude) is an IFR term (talking about it wrt VFR flight can only be confusing) and,
in the legend, on UK charts it specifically says that for the MEF "NB: THIS IS NOT A SAFETY ALTITUDE"
The MEF can, however, be an easy way to calculate the MSA (just add 1,000", or 2,000' in mountainous areas)
rather than searching all along 5nm either side of your proposed route.
Most (all?) European VFR Charts do not give MEF, but rather give an already calculated MSA for each grid.
Some IFR charts give a Minimum Sector Altitude which, confusingly, also is abbreviated
MSA (but this will always be at, or above, the Minimum Safety Altitude.
It is important to have
read the legend, on whatever chart is being used,
so that it is known what the figures represent.