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The primary responsibility of an Airport Traffic Control Tower (ATCT) controller is to prevent collisions between aircraft and other hazards on the surface and in the immediate vicinity. The safety service provided by controllers at towers with larger operations greatly exceeds the costs of establishing those towers. As the number of operations decreases, the costs of operating the tower may begin to outweigh the benefits of staffing the tower. Safety event reports describing instances where an ATCT controller provided a service that reduced the consequences of the event were collected. The reports were classified to identify latent factors, causal factors, and positive safety benefits. The adverse causal factors and positive safety benefits were then utilized to determined statistically significant risk-benefit pathways describing the safety benefits that controllers provide at airports in Class Delta (D) airspace. This paper presents the dynamic risk-benefit pathway, one of the three pathways for Class D ATCT.