O16

O16 or O-16 may refer to:
 * Curtiss O-16 Falcon, an observation aircraft of the United States Army Air Corps
 * Garberville Airport, in Humboldt County, California, United States
 * HNLMS O 16, a submarine of the Royal Netherlands Navy
 * Oxygen-16, an isotope of oxygen
 * USS O-16 (SS-77), a submarine of the United States Navy