One of the biggest falters in emergencies is the pilots failure to properly communicate the emergency. Knowing the emergency transponder squawk codes can help ATC evaluate your situation and notify help sooner or aid in getting you to the nearest airport.
Below are the 3 squawk codes every pilot should commit to memory:
7500 – Hijack
7600 – Lost Comm (radio failure)
7700 – Emergency
An easy way to remember this: 75 taken alive, 76 technical glitch, 77 going to heaven.