True mountain flying—that is, terrain, contour or drainage flying, as opposed to flying well above the mountains—can be done with total safety only when the pilot becomes conditioned to apply the basic premised during flight, without having to think about them.

Always remain in a position where you can turn toward lowering terrain.

This axiom also encompasses the idea that you will not enter or fly in a canyon where there is not sufficient room to turn around. Another way of stating this truth is to have an escape route in mind and be in a position to exercise this option.

Do not fly beyond the point of no return.

This is the position when flying upslope terrain where, if you reduce the throttle to idle and begin a normal glide, you will have sufficient altitude to turn around without impacting the terrain.
 

Constantly evaluate where you are and decide if you can lose altitude before having to turn the airplane. If not, you are narrowing your options substantially.

What happens when the pilot flies beyond the point of no return? First, and usually the less serious consequence, involves landing the airplane straight ahead into whatever terrain exists. This normally results in destruction of the aircraft, but with proper technique the occupants will survive. Proper technique means the airspeed is maintained to allow transition to a normal landing attitude (often upslope terrain) without stalling the airplane.

The second outcome of flying beyond the point of no return involves the stall-spin accident. Because there is insufficient altitude or manoeuvring space to complete the turn around, the pilot may try to hurry the turn with excessive bottom rudder, thus yawing the airplane. This induces a stall-spin.