Figure 5-4.  Performance-based objectives are made up of a description of the skill or behavior, conditions, and criteria.  Conditions explain the rules for demonstration of the skill. If the desired objective is to navigate from point A to point B, the  objective, as stated, is not specific enough for all learners to do it in the same way. Information such as equipment, tools, reference  material, and limiting parameters should be included. For example, inserting several conditions narrows the objective as follows:  “Using appropriate charts, a prepared flight log, and training aircraft, navigate from point A to point B while maintaining standard  hemispheric altitudes.” Sometimes, in the process of reading the objective, someone might say, “But, what if ...?” This is a good  indication that the conditions are confusing and need clarification.  Criteria are the standards that measure the accomplishment of the objective. Good criteria define performance so there can be no  question whether or not the performance meets the objective. In the previous example, the criteria may include that navigation from  point A to point B be accomplished within 5 minutes of the preplanned flight time and that en route altitude be maintained within 200  feet. The revised performance-based objective may now also include arrival at point B within 5 minutes of planned arrival time and  cruise altitude should be maintained within 200 feet during the en route phase of the flight.” The alert reader has already noted that  the conditions and criteria changed slightly during the development of these objectives. In real-world objective development, that is  exactly the way it will occur. Conditions and criteria may be refined as necessary.  ACS documents hold an important position in aviation training curricula because they supply the instructor with specific performance  objectives based on the standards for the issuance of a particular aviation certificate or rating.  [Figure 5-5]  The FAA frequently  reviews the ACS test Areas of Operation and Tasks to maintain their relevance to the current aviation environment. Test items  included as part of a test or evaluation should be both content valid and criterion valid. Content validity means that a particular  maneuver or procedure closely mimics what is required in actual flying. Criterion validity means that the completion standards for the  test are reflective of acceptable standards.  For example, in flight training, content validity is reflected by a particular maneuver closely mimicking a maneuver required in actual  flight, such as the learner pilot being able to recover from a power-off stall. Criterion validity means that the completion standards for  the test are reflective of acceptable standards in actual flight. Thus, the learner pilot exhibits knowledge of all the elements involved  in a power-off stall as listed in the ACS.  Conditions  Criteria  The Importance of the ACS in Aviation Training Curricula  5-6 