There are an infinite number of combinations that can cause trouble, and many times the recovery from the error-producing condition will be instinctive rather than cognitive. However, this training will help you to recognize and to respond to error-producing conditions. The following are the twelve most common human maintenance errors as identified by aviation safety specialists. They are known collectively as the “Dirty Dozen“. We will explore these types of human factor errors more fully in part three of this program. The dirty dozen is by no means an exhaustive list, so after you finish, try and think of your own human factors-related errors and ways to overcome them.