Canoas Air Force Base — Porto Alegre, Brazil

QNS refers to Canoas Air Force Base, a major Brazilian Air Force installation located near Porto Alegre, the capital of Rio Grande do Sul state in southern Brazil. As a military facility, QNS has historically hosted fighter and transport squadrons and plays a key role in Brazil's southern air defense, given the base's proximity to the borders with Uruguay and Argentina. Canoas has at times shared operations or infrastructure considerations with Porto Alegre's civilian Salgado Filho International Airport nearby, though QNS itself remains under military control rather than handling scheduled passenger traffic. The base's location in the densely populated Porto Alegre metropolitan area underscores its strategic importance to Brazilian air power in the country's southernmost region.