FAA 107 Commercial Drone Pilot Practice Exam

A stable air mass is typically characterized by its ability to support moderate to good visibility. This is due to the lack of significant vertical air movement, which often helps keep particulate matter, like dust or moisture, from being stirred up and creating haze. Under stable conditions, the air tends to remain stratified, preventing turbulence and helping maintain clarity in the atmosphere. While options indicating turbulence or rapid changes in temperature suggest unstable air, these features are actually more prevalent in unstable air masses. Frequent turbulence occurs when there is significant vertical movement of air, which is the opposite of what you would expect in a stable air mass. Similarly, rapid temperature changes often indicate an environment where air is mixing vigorously and creating instability. In summary, the hallmark of a stable air mass is indeed good visibility due to a lack of turbulence and air mixing, making high surface visibility a common characteristic, while poor visibility would typically be associated with instability, where conditions are right for turbulence and other atmospheric disturbances.