3-33  Kinds of Errors  Errors  Slip  Mistake  Reducing Error  Learning and Practicing  Taking Time  Checking for Errors  Another way to help avoid errors is to look actively for evidence of them. Many tasks in aviation offer a means of checking work.  Learners should be encouraged to look for new ways of checking their work.  Errors can often be reduced by working deliberately at a comfortable pace. Hurrying does not achieve the same results as faster  performance that is gained by increasing one’s skill through continued practice.$_{ }$ The first line of defense against errors is learning and practice. Higher levels of knowledge and skill are associated with a lower  frequency and magnitude of error.  Although it is impossible to eliminate errors entirely, there are ways to reduce them, as described in the following paragraphs.  Experts are not immune to making mistakes, which sometimes arise from the way an expert draws upon knowledge of familiar  problems and responds to them using familiar solutions.  [Figure 3-21]  Mistakes can occur when the expert categorizes a particular  case incorrectly. For example, an experienced pilot may become accustomed to ignoring nuisance alerts issued by his traffic alerting  system when approaching his home airport, as many aircraft on the ground turn on their transponders prior to takeoff. One night, he  ignores an alert that was generated not by an aircraft on the ground, but rather by another aircraft that has turned in front of him on  final approach.  A mistake occurs when a person plans to do the wrong thing and is successful. Mistakes are errors of thought. Mistakes are  sometimes the result of gaps or misconceptions in the learner’s understanding. One type of mistake happens when a learner$_{ }$ formulates an understanding of a phenomenon and then later encounters a situation that shows how this understanding was incorrect  or incomplete. For example, overly simplistic understanding of weather frequently leads inexperienced learners into situations that are  unexpected.  Time pressure is another common source of slips. Studies of people performing a variety of tasks demonstrated a phenomenon called  the speed-accuracy tradeoff. The more hurried one’s work becomes the more slips one is likely to make.$_{ }$ Other forms of slips happen when someone is asked to perform a routine procedure in a slightly different way. For example, Beverly  has been assigned runway 30 for many days in a row. This morning she approaches to land and ATC assigns runway 12 instead. As  she approaches the traffic pattern, she turns to enter the pattern for runway 30 out of habit.  A slip occurs when a person plans to do one thing, but then inadvertently does something else. Slips are errors of action. Slips can  take on a variety of different forms. One of the most common forms of slips is to simply neglect to do something. Other forms of slips  occur when people confuse two things that are similar. Accidentally using a manual that is similar to the one really needed is an  example of this type of slip.  There are two kinds of errors: slips and mistakes.  Errors are a natural part of human performance. Beginners, as well as the most highly skilled experts, are vulnerable to error, and this  is perhaps the most important thing to understand about error. To believe people can eliminate errors from their performance is to  commit the biggest error of all. Instructors and learners alike should be prepared for occasional errors by learning about common  kinds of errors, how errors can be minimized, how to learn from errors, and how to recover from errors when they are made. 