unscheduled maintenance(the maintenance carried out, not in accordance with an established time schedule, but after reception of an indication regarding the state of an item Found on Those unpredictable maintenance requirements that had not been previously planned or programmed but require prompt attention and must be added to, integrated with, or substituted for previously scheduled workloads. McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright й 2003 electropedia.orgAlexander Demidov)
