Radio Navigation Simulator

[ft]

Another thread prompted me to post a link to an excellent radio navigation simulator that's freely available online. It is a great tool for getting your head around the issue of using a VOR or ILS. I figured it was worthy of a thread of its own in this forum, as I haven't seen it posted before.

http://www.luizmonteiro.com/learning_vor_sim.aspx

Cheers,
/Fred

[RedRavenSounds]

Another thread prompted me to post a link to an excellent radio navigation simulator that's freely available online. It is a great tool for getting your head around the issue of using a VOR or ILS. I figured it was worthy of a thread of its own in this forum, as I haven't seen it posted before.

http://www.luizmonteiro.com/learning_vor_sim.aspx

Cheers,
/Fred

Back in the day, VOR and ADF were all you had - GS/Loc were IFR tools anyway, and generally for "the big guys"
Easiest way to think of a VHF Omni-range is that its like a bicycle wheel with spokes (an infinite number of spokes) These spokes radiate out from the station and you "intercept" a spoke, on using the VOR portion of your nav receiver (you tune the receiver to the frequency of the VOR station, and a flag tells you if you are going towards or away from the station. The VOR station radiates another signal that is stationary (the bicycle wheel signal is literally rotating) Thus you have a phase comparison of the fixed signal and the rotating signal. That phase difference becomes what the VOR receiver detects, process and sends to the VOR indicator. The course deviation indicator (CDI) needle tells you how many degrees from a particular "spoke" you are. You use the Omni Bearing Selector (OBS) knob to "select" a spoke. When that spoke is selected the CDI needle centers. The VHF signal is line of sight and at altitude you can capture a given VOR from a significant distance. If you deviate from the selected "spoke" course - the CDI moves to either the left or the right. As you move closer to the station the deviation becomes less and less and the CDI needle begins to wander around - It becomes unusable when you are almost on top of the station, and the flag drops, telling you the signal is not reliable. As you begin to move away from the station the "to-from" flag flips over to the "from" and the reliability flag goes away. Again as you depart the station, the CDI stabilizes on a selected heading.

That is it in a nut shell - - you can tune 2 VOR's if you have two receivers, and two indicators, and determine your exact location through triangulation. You want to plan your route so that you are never directly overflying the VOR station, but selecting your next VOR before the CDI gets too sensitive.

Again in a nutshell the glide slope and the localizer are much like the VOR, but with much more sensitivity, and the glide slope "stood on its head" to provide vertical situation information referenced to the runway threshold and the localizer providing accurate horizontal situation information, referenced to the runway. The marker beacons (at 75MHz) provide additional information for distance from the runway threshhold (Outer at 5 miles, middle and finally the inner marker which is very close to the threshold). Its amazing that this system has been around for so many years and still very reliable. BTW, the Automatic Direction Finder (ADF) operates very close to the AM commercial radio band, and in fact you can "home in" on a commercial radio station. Its been around since the early 30's. It has a compass rose on it and a needle which points either to the station or its reciprocal heading. Gee - all of this before GPS Cindy's nutshell avionics briefing LOL

[Great Ozzie]

Are you getting this Air Cadet Attwood!?