Originally Posted by
Check Airman
Unless the definition of emergency has changed, why would a diversion ever fall into this category?
Quote from a training handout:
"The “MAYDAY” declaration is used when all opportunities to protect final reserve fuel have been exploited and in the judgment of the Commander the flight will now land with less than final reserve fuel remaining in the tanks."
The diversion itself is no reason to declare a MAYDAY, it's down to how much fuel you have left.