What does a CDI indicate when centered during a VOT test?

During a VOT (VOR Test Facility) test, when the Course Deviation Indicator (CDI) is centered, it indicates that the aircraft is positioned directly on the 360º radial of the VOR facility. The CDI displays lateral deviations from the selected course, and when it is centered, it signifies that the aircraft is on the exact radial that corresponds to the selected course.

In the context of a VOT test, the facility broadcasts a specific signal, allowing pilots to confirm the accuracy of their VOR receivers. When the CDI is perfectly centered and the aircraft's heading aligns with the VOT's indicated radial, it indicates that you are exactly on the 360º radial. Understanding this helps pilots ensure that their navigation equipment is functioning correctly and reinforces the importance of maintaining situational awareness when navigating with VOR systems.