A SID is an air traffic control coded departure procedure that has been established at certain airports to simplify clearance delivery procedures. SIDs are supposed to be easy to understand and, if possible, limited to one page.
Although a SID will keep aircraft away from terrain, it is optimized for air traffic control route of flight and will not always provide the lowest climb gradient. It strikes a balance between terrain and obstacle avoidance, noise abatement (if necessary), and airspace management considerations. In order to legally fly a SID, a pilot must possess at least the current version of the SID's textual description. SIDs in the United States are created by either the military (the USAF or USN) or the FAA (which includes US Army fields). The main difference between US military and civilian SIDs is that military SIDs depict obstacles, ATC climb gradients, and obstacle climb gradients, while civilian SIDs depict only minimum obstacle climb gradients.[1]