Vor Aircraft - We have had several reports of very high frequency omnidirectional area (VOR). Check out our introduction and CFI posts on VOR service volume and some questions that may come up on your exam. Now we are filming tracking to and from the VOR station. This post is an excerpt from the Pilot's Handbook of Aeronautical Knowledge (FAA-H-8083-25A).
First, tune the VOR receiver to the frequency of the selected VOR station. For example, 115.0 receives the Bravo VOR. Next, check the tags to make sure the desired VOR is being received. Once the VOR is properly tuned, the yaw course needle will deviate either to the left or to the right. Then turn the azimuth dial on the course dial until the course offset needle is centered and the TO-FROM indicator indicates "TO".
Vor Aircraft
If the needle is centered on the "FROM" mark, the azimuth should be 180°, because in this case you want to fly to the "TO" station. Now, rotate the aircraft in the direction indicated on the VOR azimuth selector or course selector, 350° in this example.
How Vor Approaches Work
If the 350° course is maintained in a starboard wind as shown, the aircraft drifts to the left of the intended track. As the aircraft departs, the VOR course deviation needle will gradually move from center to right or indicate the desired radial or track direction.
To return to the desired radial, the aircraft must turn right. As the aircraft returns to the desired track, the yaw needle slowly returns to center. When centered, the aircraft is on the desired radial and the left should be turned towards, but not the original 350° heading, as the wind offset correction must be determined. The amount of correction depends on the wind strength. If the wind speed is unknown, trial and error can be used to find the correct direction. Let's assume that in this example the 10° correction of the 360° direction is maintained.
Maintain a 360° bearing, assuming the course deviation begins to shift to the left. This means that the 10° wind correction is too large and the plane will of course fly to the right. A small left turn should be made to allow the aircraft to return to the desired radial.
When the deviation needle is centered, a small wind deviation correction of 5° or a heading correction of 355° should be flown. If this correction is sufficient, the aircraft will remain on the radial. Otherwise, small variations in direction must be made to keep the needle centered and thus the aircraft radially aligned.
Vor Tracking, Bracketing
When the VOR station is passed, the course deviation needle will change, then settle, and the "TO" indicator will change to "FROM". If the aircraft passes the other side of the station, the needle will deviate in the direction of the station when the indicator changes to "FROM".
In general, the same techniques are applied to tracking an outbound trip as to tracking an inbound trip. If the intention is to fly over the station and follow the outbound direction opposite the inbound radial, the heading selector should not be changed. Corrections are made in the same way to keep the needle in the center. The only difference is that the multi-directional range indicator indicates "FROM".
If the outbound route is followed on a course other than the opposite of the inbound radial, this new course or radial must be set in the course selector and a turn made to break this course. Once this rate is reached, follow-up procedures are the same as before. This week's posts focus on the VOR, a radio navigation system used by private and commercial pilots around the world. This introduction is from The Student Pilot's Flight Manual by William Kershner.
The most useful radio navigation aid en route other than GPS is the VHF omnirange or VOR as it is sometimes called. The VOR frequency range is 108.00 to 117.95 MHz and it uses the principle of electronic angle measurement. The VOR provides two signals. One is omnidirectional (or omnidirectional) and the other is rotary signal. An omnidirectional signal contracts and expands 30 times per second, and a rotary signal rotates clockwise 30 times per second. A rotating signal has a positive and negative side.
Vors: Avoiding Confusion With The To / From Flag
Your Omni receiver receives a signal in all directions. After some time, it gets the highest point of positive rotating signal. The receiver electronically measures the time difference, and it is expressed in degrees
Bearing relative to the station (Figure 1). For example, suppose it takes a minute instead of 1/30 of a second to make one revolution of a rotating signal. You get an omnidirectional signal and 20 seconds later you get a rotating signal. This means your position is 20/60 or 1/3. (One-third of 360° is 120°, and you are at 120 radians.) A VOR receiver does this in a faster and more accurate way.
The representation of an aircraft VOR receiver consists of four main parts: (1) a dial to select the station frequency to be used; (2) an azimuth or omni-bearing selector (OBS) calibrated from 0 to 360; (3) course deviation indicator (CDI), a vertical needle that moves left or right; and (4) a TO-FROM pointer. Figure 2 is a type of VOR receiver.
Let's say you want to fly to a specific VOR, say 30 miles away. First you tune the frequency and
Vintage Cessna Aircraft Course / Vor Indicator, In 317a 1, 27490 R
. You should have an idea where you are relative to the station, but if not, turn the azimuth or heading dial until the offset indicator or needle is centered and the TO-FROM indicator says TO. Read OBS. This is your VOR course. If you turn on this magnetic heading and keep the needle centered, you will fly directly over the VOR. If TOFROM says TO and you're going to the station, fly the needle. If the needle moves to the left, the selected bearing is to the left and you turn the plane in that direction and fly until the needle is in the center again. You need to adjust the air retention in the selected bearing (Figure 3).
. (Radials are like surfaces from a VOR.) (See Figure 3A.) Radials are numbered from 0 to 359, so if a station asks where you are, you say, "I'm going to station 120 (one-two) -zero) radial." For example, if there is a westerly wind, the engine may drift from the selected bearing as shown in Figure 3B, and the LEFT-RIGHT needle will look like Figure 4.
Figure 4. Head pointer and two types of VOR indicators. The selected radial is on the left.
The angle of correction or "cut" depends on how far you drift on the course. Usually 30° is the maximum at some distance from the station. It may take some time for the needle to refocus if you are far away. When the needle returns to center, return to the original direction, but this time Include the estimated wind correction in the compass or direction finder. Observe the needle and make further corrections if necessary.
Idme 891 Narco Vor / Loc / Glideslope Indicator
When you cross a station, the TO-FROM pointer will vibrate and then decrease to FROM. The receiver now says you are 300° from the station. Always make sure the OBS is set close to the compass direction. This way the needle always points towards the selected radial. If you turn around and return to the station after passing its 300° course and the bearing dial is not reset in the same direction you were traveling, the needle will move in the opposite direction.
The detection is wrong if you adjust the needle and the needle moves further from the center as you fly.
But back in the station corridor: TO-FROM says FROM and your plane is 300° from the VOR, so the needle is right. Continue flying the needle as you did before arriving at the VOR.
Most omni needles are set so that the full deflection from center is 10° or more. If the needle is bent halfway, you can guess that you are about 5° from your chosen bearing.
Narco V0a 5 Vor/ils Nav Converter/ Indicator Pn K 04157 2
VOR field accuracy is typically ±1°, but some stations in mountainous terrain may have greater error than this on some radials or may not be usable below certain altitudes; it is worth mentioning One of the oldest and most useful aids to navigation is the VOR system. The system was built after World War II and is still in use today. It consists of thousands of ground-based transmitter stations, or VORs, that communicate with radio receivers aboard aircraft. Many of the VORs are located on airways. The Victor airway system is built around the VOR navigation system. Ground VOR transmitter units are also available at airports where they are known as TVORs (terminal VORs). The US military has a navigation system
Vor antenna aircraft, vor, vor orl, vor gol, vor motorcycles, vor orm, vor receiver, vor tacan, vor osp, vor antenna on aircraft, vor tech, aircraft vor
0 Comments