Originally Posted by
sonicbum
Correct, but a PAN does not allow You to deviate from the acknowledged clearance, hence a MAYDAY is required.
I think every rulebook every written regarding aviation contains a version of the following:
§ 91.3 Responsibility and authority of the pilot in command.
(a) The pilot in command of an aircraft is directly responsible for, and is the final authority as to, the operation of that aircraft.
(b) In an in-flight emergency requiring immediate action, the pilot in command may deviate from any rule of this part to the extent required to meet that emergency.
(c) Each pilot in command who deviates from a rule under paragraph (b) of this section shall, upon the request of the Administrator, send a written report of that deviation to the Administrator.
Aviate, navigate, communicate. It’s the nature of the emergency in itself that allows you to deviate from your clearance, not the words mayday in itself. Don’t get me wrong, I have no hesitation to declare an emergency, especially at the early stages of an engine failure after takeoff. I just want to make sure we don’t put the cart before the horse. The controller is not in command, we are.