With all this talk of approach and departure angles, I looked in my files and found this from a post some time ago:
One good way is to stand at the landing point, extend your arm out in front of you to and bend your wrist so that your palm is facing you at eye level. Put the lowest finger on the horizon, parallel with it, and count the number of fingers up until the obstacle is cleared. Each finger is about 3 degrees, so 4 fingers gives you your 12 degrees. You can also do this sitting in the cockpit to judge climb out power requirements.
Another good trick is to extend your left leg to your left side about shoulder width away from your normal standing position. As you shift your weight onto your left leg, violently shift your right leg forward at least 3 feet with your head down. From this position, gently extend your right arm. When fully extended, clench your fist, grit your teeth, look up and extend your middle finger. This is how to greet a fixed wing pilot.
