It was in Korea. The year was 1970. I was a "green bean", term for a new comer to the ROK, from a stateside AFB. Somewhere in that 13 month tour, I heard the expression, "Let the rough end drag, the slick end slide!" To this day, 40= years later I still DO NOT know what that was supposed to mean. I remembered it one day sitting in a crash truck awaiting a crippled aircraft, sans landing gear, heading for the runway...and the trucks had foamed the runway, and I burst out laughing. My young driver said, "This funny, for you!?" He was going to save the world as a young firefighter. I looked at him, and repeated the remark..."When that bird slides on the runway, we'll let the rough end drag and the slick end slide!" He was confused. A/C landed, slid. Pilots were OK. And yes the dragging and sliding took place!