Online VOR simulator to practice radials and courses

A VOR is a navigation aid that lets you determine 360 magnetic radials from a ground station (antenna). In navigation, it helps you understand your position in the airspace.

A VOR radial is an imaginary “line” created by radio frequency; it extends outward from the VOR station. Each radial is identified by its magnetic bearing from the station, from 1 to 360 degrees. For example: in Brazil, the 090 radial lies east of the station.

Tune the station, confirm on the OBS instrument that a signal is being received, and turn the OBS until the CDI (vertical line) centers with a FROM indication. The course you get corresponds to the radial you are on.

The radial originates at the VOR station and extends outward. The course is where the pilot wants to go, whether the station is ahead or behind. A course does not define the radial you are on. What defines the current radial is only the aircraft’s position, regardless of the path (course) the airplane will follow and regardless of where the nose is pointing (heading).

FROM means the selected course leads away from the station. TO means the selected course leads toward the station. Keep in mind that the course does not necessarily define the radial you are on, but it can coincide with it, in which case the CDI is necessarily in the FROM position.

The CDI shows which side of the aircraft the selected course is on, with either a TO or a FROM indication: if the CDI is to the right, the course is to the right of the aircraft; if it is to the left, the course is to the left. This holds as long as the aircraft’s heading roughly matches (precisely, less than 90° from the selected course.

Select the desired course on the OBS and check whether the indication is TO or FROM. If it is TO, fly a heading equal to the course until you pass the station and the indication changes to FROM. With FROM showing, choose an intercept heading that takes the aircraft to the course. Reduce the intercept angle as the CDI approaches the center and, within 2.5° of the course, press NAV so the autopilot keeps the aircraft on it (and now also on the radial). If the indication is already FROM from the start, there is no need to cross the station: go straight to the heading that matches the course and line up with it.

No. The radial indicates the aircraft’s position relative to (around) the station. Any object, with or without a nose, and pointing in any direction, is around the station, that is, it is on a radial. The course to fly is a desired direction that may or may not coincide with that of a radial. It depends on where you want to go and on the moment.

Use an online VOR simulator to practice reading the OBS, heading, and TO/FROM interception. VOR Trainer is excellent for this. Once you have mastered simple interception, you can use the app’s feature that makes training easier with radial changes greater than 90 degrees.

Yes. VOR Trainer was designed to work on mobile devices too and can even be installed as a PWA app (Add to Home Screen feature).

Obviously not. It is an excellent complementary tool for practicing instrument reading and radial interception, and for building situational awareness through its interface features.