Aviation calibration testing ensures that measuring tools and equipment are working correctly. When an instrument continually passes testing without fail, and did not require any adjustment, many wonder if the next step should be lengthening the calibration due date. On the other hand, if equipment constantly requires repair or frequently fails testing, should the calibration interval decrease? There are multiple factors to consider, especially for MROs and FBOs that must observe FAA mandates. Answer the questions below to determine if changing calibration intervals is the best choice.