What is the designation for airspace that is not prohibited but could be dangerous to fly in due to military testing activities?

The designation for airspace that is not prohibited but could be dangerous due to military testing activities is known as Warning Areas (W-###). These areas are established to warn pilots of potential hazards associated with military operations, such as training exercises that might involve live munitions or other potentially dangerous activities.

Restricted Areas (R-###) are indeed airspaces where flight is prohibited without permission, typically used for military operations that can pose a danger to non-participating aircraft.

Military Operations Areas (MOAs) are designated for military training where aircraft can operate, but the airspace is not off-limits to civilian aircraft. While MOAs indicate that military activities are occurring, they do not inherently represent a danger like Warning Areas do; they are advisory in nature.

Alert Areas are established to caution pilots about a high volume of pilot training or unusual aerial activity, but again, they do not carry the same level of potential danger associated with the activities in Warning Areas.

In summary, while Restricted Areas prevent access entirely, Warning Areas serve to notify pilots of hazardous conditions without restricting access outright, which is vital for situational awareness when flying near military testing.