MSL?

[OBIO]

I know that ASL means Above Sea Level. AGL means Above Ground Level. What does MSL mean when you have the Shift Z info displayed?

OBIO

 

[leroy10]

Hi OBIO,

MSL= mean sea level

 

[robert41]

Very simply, mean sea level is the reading on the altimeter if the baro pressure is set correctly.

 

[glennc]

Robert,

Not in the US. Mean Sea Level means the water level average around the world. If the altimeter is set to the correct reading, the altitude of the field above seal level is what will be on the altimeter. That's the different between QNH and (I can't remember the the other term).

Glenn

 

[srgalahad]

Mean sea level (MSL) is a measure of the average height of the ocean's surface (such as the halfway point between the mean high tide and the mean low tide); used as a standard in reckoning land elevation.

Mean sea level does not remain constant over the surface of the entire earth. For instance, mean sea level at the Pacific end of the Panama Canal stands 20 cm (8 in) higher than at the Atlantic end.
http://www.ask.com/wiki/Sea_level

As far as MSFS is concerned, the actual SHIFT-Z line reads ALT xxxx.x ft MSL so what you are being given is the height of the aircraft reference point (as set in the .mdl) above Mean Sea Level. Note that the a/c ref pt is not normally the wheels but the fixed point around which the model is built -- which is why the Aerodrome elevation is not the same as the SHIFT-Z number when you are sitting on the runway.

Rob

 

[glennc]

The term I couldn't remember is QFE. QNH is the setting that results in displaying the aircraft's altitude above MSL, QFE is the setting that results in the altitude above ground level where the reading was made.

Glenn