What plays a key role in airfield safety related to structures and obstacles?

Frangibility refers to the design characteristic of certain structures and obstacles that allows them to break away or collapse under specific conditions, such as an aircraft impact. This is crucial for airfield safety because it minimizes the risk of injury to aircraft occupants and damage to the aircraft itself in the event of a collision with obstacles. Structures that are designed to be frangible, like certain types of light poles or antennas, are engineered specifically to reduce potential hazards, making them safer for aircraft operating in proximity to the airfield.

In contrast, weight tolerance, visibility conditions, and surface quality are important factors in general aviation safety but do not specifically address the risk posed by obstacles and structures in the context of aircraft operations. Weight tolerance pertains to the load-bearing capacities of surfaces and aircraft, visibility conditions affect pilot perception and navigation, and surface quality relates to the condition of runways and taxiways but does not directly influence the safety of structures and obstacles near the airfield in the same way frangibility does.