Originally Posted by
vee-tail-1
Hmnn... If like me, you only fly day VFR/VMC at flight levels over the UK, then only two pressure settings are needed. Standard 1013.2 & QFE (or A/F QNH if you like a bit more mental arithmetic)
You are very lucky to always fly in areas where there are no airways of other CAS defined as an altitude.
For most of my VMC non-airways flying I use the altimeter to ensure avoidance of airspace (as I can see the ground to avoid that and eye ball a landing pattern so the altimeter is more of a convenience than a necessity for these)