Why was I woken up last night by aircraft noise; what’s going on at the Airport?

Like most commercial airports in the US, Sky Harbor, Deer Valley, and Goodyear Airports operates 24 hours per day 365 days per year. There is no nighttime curfew . However, the City of Phoenix, in coordination with the FAA, airport users and community representatives, has developed preferred nighttime aircraft procedures that help mitigate aircraft noise over residential areas. Wind and weather permitting, these procedures are designed to keep aircraft over less populated areas as much as possible.