Close Air Support
Mission performed by air forces in support of ground troops. Involves the dumping of extremely nasty, air delivered ordinance on baddies who are giving your chaps a bit of trouble up close and personal.
In olden days (well, up till 15years ago) this involved the pilot taking his best shot and everyone with friendly leanings curling up in a ball at the bottom of his shell scrape and hoping for the best.
In these days of GPS, laser guided munitions, computers and highly trained pilots of the RAF, USAF and USAAC ... its still a case of curling up in a ball at the bottom of a shell scrape and hoping for the best.