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VOR tracking for the vertically challenged

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Good Evening All,I've spent the last couple months of my free-time trying to teach myself some basic navigation techniques. Right now I'm working on VOR tracking in low-altitude airways. Tonight I made a mistake, and I'm hoping someone can set me straight.To set the stage, I was tracking the outbound radial from the Yakima VOR station (HDG285), and everything was going fine until I approached the KSEA ILS transmitter and tuned it in. This occured where I have circled in red below. Immediately the course deviation indicator told me I was too far right. I corrected my course to the left, but could not center on the signal, the CDI just kept indicating that the ILS was to the left. To make a long story short, when the CDI finally indicated it was time for final approach (CDI centered), I was well south of the runway. Had I not been familiar with the Seattle area, it would have taken me too long to figure out what had gone wrong (I was very low on fuel, which is the subject of another post to be).Now I know that the route that I flew probably broke every rule in the book, and it looks like a couple of drunken pilots had control of the plane (I have two in mind ;)). My question is, does anybody know where I went wrong? Is the ILS really only meant for the final approach? Any guidance (no pun intended) would be appreciated.Misdirectionally yours - Clueless in San Diego

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I wish I could help but the same think happened to me at KIAG, unfortunately, I believe it is more likely a bug in the ILS than something the user has done wrong. However, I am very unfamiliar with the effects of VOR/ILS being used together, so I'm most likely wrong. So if anybody can offer guidance, I too would appreciate it.Scott

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Hi David,IFR flying can really be exciting, can't it? Sometimes almost too exciting! Especially if it is the real world and you can't see ANYTHING out the windows! SCARY! But let me see if I can tackle your problem. Don't know if my answers will be exactly right, but maybe they can help a bit.Regarding one of your last questions, "Is the ILS really only meant for the final approach?" The answer is yes and no. The ILS needle can definitely help at any point but it should not be the final determination until you really know you are nearing the final approach area--getting near the Outer Marker for the runway you want to land on.As shown by your example case, the ILS needles will help you align with the runway but won't tell you clearly whether the runway is ahead of you or behind you--at least not until it might be too late and, as happened to you, you end up flying away from the runway rather than towards it. And as you pointed out, that can be REALLY bad if you are low on fuel! :)In your particular situation, I feel you really needed to add an intermediate step during your flight planning. You need to plan on entering into a standard landing pattern. You should not be thinking about being headed to a particular airport or even a particular runway but rather headed for that magic spot that will put you into the correct standard approach pattern.There are many online tutorials and books that diagram what a standard approach pattern looks like--sort of a rectangle with the runway in the middle of one side of it. There is a reason why it is so widely used in tutorials--it works! :) If you don't have a picture of one to look at, let me know and I will send you one. My email address is at the bottom.Using a standard approach pattern is certainly not the only way to do it, but it will work! And in almost any situation--especially when you are going into an unfamiliar airport with out using ATC to tell you where to go. And you need to be able to always "see" that pattern in your mind even if you are not looking at the GPS or Map View.All of the following assumes starting at that red circle you drew on your screen print--probably still some 40-80 nm out from the airport. Even though the ILS needle became active fairly early, you still needed to be tuned into a VOR or NDB that would lead you north of the airport first--or at least directly towards it so that you would not end up south of it.In this case with an intent to land on a southerly heading into 16R or 16L, you could use the SEA VOR and first head directly towards that which would head you directly toward the center of the airport. Then once your DME indicated you were still around 15 nm away, you turn northerly to a heading of 320 (that's the back course heading for the ILS and runway heading of 160 for 16L or 16R) to enter a standard left turning landing pattern. You would then be flying parallel to the runway and parallel to the localizer.Also by this time you need to have gotten your altitude and airspeed down closer to pattern altitude and airspeed. What they should be depend greatly on what type of aircraft you are flying. Check the references and know what they should be.It won't be cruise speed or cruise altitude but it also won't be landing speed or ground level. But it will be something closer to the latter. For a heavy it may be 200 kts and 2400' AGL. For a Cessna it might be more like 80-110 kts and 12-1500' AGL.The type of airport might effect both as well. For larger major airports, the numbers tend to be somewhat larger, whereas with the smaller fields, both numbers tend to be smaller.During that turn you would probably get even closer to KSEA--maybe 10-12 nm on your DME. But as you came out of the turn to a heading of 320 you would see the DME stop decreasing and even begin increasing again as you start going north of the airport.You would then fly northerly on that heading of 320 until you are again showing on your DME that you are back out at least 15-20 nm or so away from the SEA VOR. Then turn westerly on a heading of 230 so that you will be headed towards crossing the runway heading at a right angle to it. You also still need to be reducing altitude and airspeed down closer to the approach numbers.You would maintain that for only a couple minutes and then turn a bit more southerly to a heading of approximately 185. That would put you on a heading that would intercept the ILS somewhere around the outer marker and put you on final approach. In general, the outer markers are usually somewhere around the "feather" end of those yellow or green ILS arrows on the GPS or Map View screens. At this point, you should definitely be down to approach altitude and airspeed.If you was using the autopilot (AP), that would be the point--as soon as you get turned to that heading of 185--you would engage the APR button and let the AP take you in. As soon as you intercept the Localizer, you would see the AP turn off the HDG light and turn the aircraft directly in line with the runway. Likewise as soon as you intercept the glideslope, you would see the ALT light go out and the aircraft will begin it's descent. The AP will gradually get you centered on both of those but it may take a short while for all those adjustments to be made--have some patience with it.If you are not using or don't have an AP available, then you still have to do what the AP would do--you need to intercept the Localizer beam while still outside of the outer marker and still below the glideslope.Then you turn to the final heading lined up on the localizer and watch for the Glideslope needle to start falling. As it just about reaches center, then you back off some more on the throttle and begin a standard rate of descent for your aircraft and try to keep both needles relatively close to centered.That should get you down safely to flare out altitude a few feet above the runway. As you level out just above the ground, cut throttle and let it settle down gently on it's own.Try not to "fly it to the ground" with the elevator. If you have gotten the airspeed down where it needed to be before beginning your descent, then because you have leveled off and cut throttle, airspeed will gradually bleed off and the aircraft will settle down on it's own.That should get you where you want to be. Let me know if anything I said does not make sense. Hope it helps.One final thought--you get a lot of practice time flying straight and level simply because that is what takes up most of the time in a flight. But you only get a relatively little time to practice the landing portion of a flight because that takes up only a relatively small amount of the total flight time.That is most unfortunate because you are spending by far the greatest amount of practice time doing the EASIST part of flying! You need to reverse that for a while. Use Slew Mode and save some flights that put you in several typical approach situations. Then practice just the approach over and over again.You will find that it will improve your enjoyment of flying tremendously as you improve your competency in doing what is probably the most important part of flying--ending the flight safely at the destination! :)Remember, any landing you walk away from is a good landing! :)Happy Flying!Bill Molonybmolony@bellsouth.netAtlanta GA USAUnder the 27L Approach to KATL--the busiest airport in the world :)PS I added a graphic that might give you a better picture of what I was trying to describe. Hope this helps!

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David,I believe I know the likely cause of your problems.You have to be doubly vigilant when using ILS on runways where both end of the the same runway use the same ILS frequency.In KSEA 16L and 34R LOC have the same frequency, also the same for the 16R and 34L pair.In real life only one end would be operational, the other would be turned off. But in the FS they have all sides always on. This could be a trap. In such case you should not use the ILS signal until you are unmistakingly on the correct side of the runway you are trying to land on. In other words if you are trying to land say on 16R you should not pay attention to the ILS signal until you are on the northerly side of the airport and vice versa, otherwise you will be reading cues to the wrong runway. In other words you must know where you are all the time and have your approach well planned. To answer your question - ILS signal should not be used for situational awareness until the last moment when you are actually about to intercept it. Localizer signal is NOT another VOR. Flying the ILS according to real approach plates would pretty much guarantee that you won't get into such trouble. I can see from your ground track you pretty much 'cooked' this approach according to your own plan. It can be done in the abscense of real plates but one must be very careful about every single detail and know what a reasonable approach, intercept angles should be like.Michael J.

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Hi Michael,Interesting way to put it. I think you said much of what I said in a much simpler way and in a whole lot less words! :) Thanks!However, I think that if you will check, you may find that all reciprocal runway headings use the same ILS frequency.And at every airport I have checked in FS2K2, the real world airport uses the same frequencies so I think MS used the real world to set up their frequency databases.Admittedly I have only looked at a tiny percentage of the thousands of airports out there but I think I see a pattern there. If you find one that does not follow the same patttern, please let me know.Happy Flying!Bill MolonyAtlanta GA USAUnder the 27L Approach to KATL--the busiest airport in the world :)

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It's actually quite simple, be sure to set up a 30 degree intercept angle to the ILS approach. Judging from your map you needed to turn right downwind then left base leg to intercept the localizer.

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>However, I think that if you will check, you may find that >all reciprocal runway headings use the same ILS frequency. I don't think it is true in general. I can't say which one is more typical case but I know plenty of examples where both ends have different frequencies. KOAK 29/11 is a good example.Michael J.

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NO THEY DO NOT! It's a backcourse if they use the same frequency and all major aiports use there own frequency even if it is a reciprocal runway.

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>NO THEY DO NOT! It's a backcourse if they use the same >frequency and all major aiports use there own frequency even >if it is a reciprocal runway. Hey Mr. R lets not muddle the issue even further. NO, the same reciprocal LOC frequency does *NOT* automatically mean backcourse approach. It could be backcourse but could also be its own ILS. And Bill is absolutely correct - there are quite a few airports where both reciprocal frequencies are identical and they are not backcourse approaches (KSEA a good example).Michael J.

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OK Mr. M.All I'm saying is that not all runways reciprocals use the same frequency. That's all.

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Bill,Thank you for your wonderfully detailed response. The bold red line was the route I had intended to take, just was thrown off by the ILS signal. The information you and Michael provided has helped immensely. I still have plenty to learn. But that's what makes this so much fun, and for me, very close to the real thing (even though I'm not a pilot).BTW - I always like to work on my landings. My favorite method is landing on the carriers with the A-6E. If you can nail those, you can handle almost anything :)

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Thank you Michael. I learned a valuable lesson today.

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Airports that use the same frequency for the ILS have a little switch that determines what runway is going to be active at that time. Some airports allow, based on the inbound traffic, an airliner to make a straight-in "type" approach without having to fly all the way around the airport to pick up the ILS on the active rwy. They just change the active runway.ILS, unless stated elsewhere ie. approach plate, etc. are only good out to 18nms. That is for the localizer, the glideslope is only good for 10nms. Remember, that's only if it's not printed otherwise. Some, like an ILS out of Berlin, if I remember right during the cold war, were to be followed all the way through East Germany. But I digress, the first three steps, in ANY instrument procedure are always 1. Tune 2. Identify 3. MonitorThe way you were coming in from Yakima, you shouldn't ever use the ILS like that to navigate. Remember the localizer CDI once against the wall, won't tell you how far away from course you are, you could be a mile, you could be thirty miles, and the ILS has a very narrow band, as indicated by the green arrows in the map view. You should have used another VOR or NDB to get close enough to pick up the ILS signal, like Bill showed earlier.Like you said though, you were able to find your way, and in the end that's what counts, but oh my, if that was an instrument checkride............Lobaeux

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Jeppeson's SimCharts are fun to play around with.

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David:As a sometimes browser, that is as someone who occasionally browses the MSFS2002 Forum on Avsim, today I ran into one of your posts and took an interest in the problem you had with the VOR Tracking and what you called a: Vertically Challenged--post. Well I wanted to give you my spiel on this one. I did not read the other posts in complete detail, but I think I can add some thing to what was said that might be helpful to you. I wanted to fly the approach, check on your problem and give you my own slant. You can get a lot of them, but try this one. Go back and fly it. I think you'll find it works quite well.First, let's do some first things first, however.In your post you said, and I quote, "

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