Hydraulic fluid flows out of the landing gear of a U.S. Air Force C-130J Super Hercules on Powidz Air Base, Poland, Aug. 3, 2018. The fluid is drained out prior to replacing an aircraft’s strut, the function of which is to ensure an aircraft could sustain hard landings on unimproved surfaces. (U.S. Air Force photo by Senior Airman Joshua Magbanua)