TAA and MSA

[funkypilot]

No, this question is not about knowing if it is allowed to fly at MSA in normal conditions... :=:=:=:=

I was just wondering, and I hope someone will be able to answer, why the PANS-OPS always considers a 25 NM radius plus a 5 NM buffer area??

Wouldn't it be faster to say 30 NM directly??

My question seems so silly that I guess I missed something...

Thanks for help

[FlyingForFun]

Just a guess.... but in the UK, Rule 33 says that you must not be less than 1000ft above the highest obstacle within 5nm. I assume there are similar rules in other countries.

So the charts will show the minimum safe and legal altitude you can fly within 25nm, according to this rule, and it does that by adding a 5nm buffer.

FFF
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