SurClaro Flight Simulator Resources

[skipperdan]

Here is a nice set of instructions for using a VOR that I just received from EAA: 8) 8)

Q. I’m still struggling to get the needle centered on VOR training. I tune in the OBS (Omni Bearing Selector), turn to an appropriate course heading and try to fly the needle while trying to pick points on the horizon as holding targets. The needle centers, then the needle swings left or right, I correct my course heading, towards the deflection, and work at finding the sweet spot.

A. Your question is a good one and asked often by flight students. The biggest mistake I find among students is the urge to make things happen too quickly. Here’s what I mean.

Flying a VOR heading or radial is no different than flying your pencil course line on the map. Remember calculating the wind correction angle in order to fly your desired course line? The same applies to the VOR, except we’re flying an electronic line rather than a pencil line.

When you are flying to a VOR:

Tune the OBS to center the needle and ensure that you have a “To” reading. Look at your heading on the directional gyro (DG). Hold the heading as steady as you can. If the needle begins to drift to the left and you’ve been holding a constant heading, you have a crosswind from the left that is pushing you to the right of your desired course.

As soon as you note the needle drifting to the left, change your heading by turning to the left, but just 10 degrees. Hold this heading constant for a minute or two. (Here is where students begin to get in a hurry. If the needle doesn’t move back to center in a few seconds, the student will begin to “chase” the needle.)

After a minute or two, check the needle. Has it moved further left? Has it begun moving right back to center? Or has it remained almost stationary with a constant but slight deflection to the left?

If it has moved further left, the wind from the left is quite strong and will require further correction. Turn left another 10 degrees and repeat until you get the needle to stabilize. Once stabilized you can make additional minor 5-10 degree corrections to the left to get the needle centered.

As the needle begins to drift back to center, you will need to reduce the wind correction angle you’ve been flying. Using a shallow bank turn, begin turning to the right about 10 degrees and then hold the heading.

As an example, let’s say the OBS originally told us that to get “To” the VOR we had a course set in of 090 degrees and we turned to 090 degrees. However, the needle drifted left. So, we turned left 10 degrees to 080 degrees. The needle stabilized telling us that we have to hold a 10-degree wind correction angle to hold the desired course. However, at this point we’re still right of course.

Then we turned another 10 degrees left to 070 degrees and the needled began drifting back to center. As the needle began moving, we initiated a shallow turn to the right back to 080 degrees. The needle is centered and remains centered until reaching the VOR.

Once crossing over the VOR, let’s say your instructor told you to track outbound on the 180 degree radial.

Turn the OBS until 180 is set under the arrow.
Turn the airplane right to 180 degree.
The needle is now right of center because of the time it took to set and make the turn. We need to intercept the radial.
Turn 30 degrees to the right (toward the needle) to 210 degrees. We’ve now established a 30-degree intercept angle.
Have patience. Depending on the winds and the speed of your airplane it may take 2-3 minutes before the needle begins moving back toward center.
As the needle moves to the center, slowly begin taking out the 30-degree intercept until you are back on the desired 180 heading and the needle is centered.
Now, if the needle drifts left or right, begin using the 10-degree wind correction angle changes as described above.
It will take both practice and patience to get and keep the needle centered. Also, you’ll need to be very conscientious on holding exact headings.

Here is a review for using the VOR:

To intercept and fly a radial away from a station, the pilot should turn the OBS until the desired radial is on top of the VOR indicator. With that done, the “To/From” indicator should show a “From” indication and the CDI will deflect in the direction that the pilot must turn to intercept the desired radial. In other words, turn toward the needle.

To fly directly to a VOR station, turn the OBS until the CDI needle is centered with a “To” indication. The heading to the VOR station is on the course index. All you need to do is turn until the aircraft’s heading matches the number on top of the course index. If there is no wind to blow you off course, flying this heading will take you directly to the station. Adjust the CDI to keep it centered since your objective is to fly to the beacon and not to track any specific radial.

To fly a specific VOR radial inbound to a VOR station, use the OBS to place the radial you want to fly inbound on the reciprocal course index on the bottom of the VOR indicator. You should have a “To” indication, and the CDI needle will deflect in the direction you need to turn to get to the station. (Once again, turn toward the needle.)