Safe and Quiet Skies Act of 2021 This bill sets forth requirements for commercial air tour flights. Among other requirements, the bill prohibits tour flights within a half mile of military installations, national cemeteries, national wilderness areas, national parks, and national wildlife refuges; prohibits tour flights from operating at an altitude of less than 1,500 feet; requires tour flights over occupied areas (e.g., residential, commercial, and recreational areas) to be no louder than 55dbA; and allows states and localities to impose additional requirements that are stricter than the minimum federal requirements.