My various instructors have had different opinions on MSA. Certainly basing it on the Grid figures in Scotland is not very sensible. The prevailing opinion is to find highest terrain within 5 Nm of track add 300 in case of suddenly appearing wind turbines then 500 for clearance. This frequently works out very significantly higher than planned altitude particularly if you are flying a coastal route in the West or messing around anywhere near the airspace in the central belt. The opinion on when you would use it does vary. Recently qualified instructors say you should immediately make MSA if in inadvertent IMC before making a 180, older instructors agree that if you are reasonably confident of position make the 180 first and then go MSA if you do not fairly promptly return to VMC. Certainly that is what I would be doing as there is a higher likely hood of being stuck in IMC if you go higher.
Caber
