When to declare an in-flight emergency 

From Thomas Turner’s excellent FLYING LESSONS newsletter, here is a simple guideline for knowing when you should contact ATC to declare an emergency. 

Should I declare an emergency?

If I’m:

• Performing a task or procedure from the Emergency Procedures section of the Pilot’s Operating Handbook or Airplane Flight Manual;
• Violating or in danger of violating an airplane Limitation;
• Violating or in danger of violating a Federal Air Regulation (or international equivalent) with no way to rectify the situation; and/or
• The safe outcome of the flight is in any way in doubt;

then I should declare an emergency. There is no question; it is not a judgment call. Get the help you need right away.

Clear, simple, and memorable.