Henry Post Army Air Field — Fort Sill, United States

FSI designates Henry Post Army Air Field, located within the Fort Sill military reservation in Oklahoma. The airfield primarily supports US Army aviation training and operations tied to Fort Sill's role as the home of Army Field Artillery and, historically, air defense training. Named for a US Army aviator, Henry Post Army Air Field handles military fixed-wing and rotary aircraft rather than commercial traffic. It serves as a functional piece of the broader Fort Sill installation, supporting personnel movement, training exercises, and logistics for one of the US Army's key training centers. Civilian access is restricted given its status as an active military airfield.