At Eglin Air Force Base’s McKinley Climatic Laboratory, some of America’s most advanced military aircraft — including the F-35B Lightning II and the MQ-9 Reaper drone — undergo rigorous testing in a facility unlike any other.

Known as one of the largest environmental test chambers in the world, the McKinley Lab can simulate extreme weather conditions ranging from blistering desert heat to arctic deep freezes. Engineers and technicians use the facility to ensure that U.S. Air Force aircraft can perform flawlessly in any climate, anywhere in the world.

These trials help identify potential vulnerabilities, refine engineering designs, and guarantee that pilots and crews can rely on their equipment under the harshest conditions.