FAA Ground School Practice Test

During a VOR test signal check, what should the course deviation indicator (CDI) needle read when centered?

1. 0° from or 180° to

2. 90° from or 270° to

3. 45° from or 225° to

4. 180° from or 0° to

The correct answer is: 0° from or 180° to

When performing a VOR test signal check, the course deviation indicator (CDI) needle should read centered at 0° from or 180° to. This means that when you are tuned to a VOR station and you're flying directly toward or directly away from it, the CDI indicates that you are on the desired course. A centered CDI indicates that you are on the radial associated with the VOR station, either approaching it (0°) or receding from it (180°). In practical terms, a centered CDI means the aircraft's course is aligned with the signal being transmitted from the VOR station, which is crucial for navigation purposes. This checks that the VOR equipment is functioning correctly and providing accurate directional information to the pilot. The other angles represent different headings from the VOR station, which would not indicate a centered reading on the CDI during a proper signal check.