VOR Navigation
Reference: FS2002 Ground School Tex, FS9 Flying Lessonst

Now you know how to control your airplane (takeoff, flying level and landing). It’s time to go somewhere but you need to know how to find your destination.

There are a number of different ways…

The first method is known as “pilotage” and is simply navigating by visual reference to the ground. Sectional charts are used to identify landmarks such as rivers, roads, mountains and so forth. With FS this is starting to be a reasonable way to get from here to there. But it is still pretty hard since you don’t have three-dimensional views.

A second method is known as “dead reckoning” which involves the use of maps to calculate headings and distance. Then while flying you convert the distance into time using your calculated ground speed (convert indicated airspeed to true airspeed, then you factor in the wind to come up with ground speed). Visual reference to the ground is not required, this is inaccurate however because it’s hard to know wind speed and direction (you use forecast winds). This is best used in conjunction with pilotage.

It’s time to start using the instruments and the primary navigational aid for aviation is the VOR or VHF Omnidirectional Range. This is a very accurate method and works extremely well provided there are VOR transmitters in the vicinity of your flight plan. This lesson will focus on the VOR and how to navigate using it.

Other methods include Automatic Direction Finding (ADF) which is another ground-based radio method and RNAV or area navigation. RNAV is a catchall for advanced systems including VOR/DME (using a Course Line Computer), Global Positioning Systems, Inertial Navigation Systems and others including combinations of these.

The VOR transmitter is a ground-based radio that transmits 360 distinct radials emanating from the transmitter. On board the aircraft a radio receiver tunes to the VOR receiver and is able to detect the radials.

Homework assignment: Read Class 12: VOR Navigation, in the Ground School Text (FS2002); or Private Pilot Lesson 3: VOR Navigation (FS2004)

Use the VOR simulator to see the effect of relative aircraft position on the VOR instrument. Set the simulator to match the instrument graphic at the top of this page (set OBS to 100). Move the aircraft until you obtain the same indication as shown. What quadrant is the aircraft in? (answer at the bottom of this page)

Technique: The key to properly flying a VOR radial is to understand the TO-FROM indicator and these simple rules.

First, to fly TO a VOR on a particular radial, let’s say the 180 radial, you must set the OBS to the reciprocal of the radial you want to fly, in this case, 360 degrees. To fly a 090 radial away from the VOR set the OBS to the radial you want to fly which in this case is 090. Rule of thumb: When flying TO a VOR station, set OBS to the reciprocal of the radial you wish to fly. To fly FROM a VOR station, set OBS to the radial itself.

A common instruction is to proceed “direct xyz VOR.” This means from your present position, head direct to the VOR named “xyz.” To do this turn the OBS until the TO-FROM indicator changes to TO and the Course Deflection Indicator, or CDI, centers. Then fly the heading indicated by the OBS setting correcting your course as needed to keep the needle centered.

Another instruction might be “turn left heading 300 to intercept the SXC (Santa Catalina) 090 radial inbound.” The term “inbound” is a clue you will be heading TO the VOR requiring you to turn to 300 degrees on the heading indicator. Tune the Nav1 radio to the SXC VOR and set the OBS to 270 (TO the station, so set the reciprocal of 270 degrees). As you approach the radial the CDI will start to deflect to the center. Turn the aircraft to roll out on the 090 radial. The needle will be centered when you have done so and you will be headed approximately 270 degrees.

If the instruction had been to “turn right left heading 120 to intercept the SXC (Santa Catalina) 090 radial outbound,” you are being told to fly away from the VOR. Make your turn to 120 degrees on the heading indicator, tune the Nav1 radio to the SXC VOR and set the OBS to 090. Intercept and track as before.

Note that if there is wind (always in real life), you will need to fly a heading slightly off that of the desired radial course to maintain a constant track. Flying inbound on the SXC R-090 if there is a 20 knot wind coming from the northwest, say 310 degrees, flying a heading of 270 you will slowly drift off-course to the south. The CDI will drift to the right. You will need to correct by flying a heading of perhaps 275-280 degrees to compensate. The VOR needle makes it easy to do this because you can constantly see your drift and track by watching the needle.

Practice flight one: Learn To Fly – Private Pilot – Lesson 3: VOR Navigation

For some additional practice, depart KLGB and climb to 2,500 feet if heading west (180 – 360 degrees) or 3,500 if heading east (0 – 179 degrees). When flying VFR the rules dictate that you fly at an altitude of odd thousands when flying east, even thousands if west and add 500 feet if VFR. When you reach cruise altitude, tune in the Seal Beach VOR (115.70). Fly direct to the VOR from your present position. Upon reaching the VOR fly the 120 radial outbound. How do you know you’ve reached the VOR? SLI also has TACAN equipment (tactical air navigation) which provides distance measuring capability (DME, see illustration below). Technically, it is known as a VORTAC rather than VOR. This equipment gives you the distance to the VORTAC station in nautical miles.

DME instrument

Fly the 120 radial for about 15 miles, turn right 90 degrees, then fly direct to SLI again. Upon reaching the VOR depart the VOR on a heading of 250 degrees. Start looking for the Long Beach airport. It’ll be about five miles on a 280 bearing from SLI. Descend to pattern altitude enter a left downwind for 25L and land.

VOR sumulator answer: Northwest. Very near West on the compass rose.


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