When I entered everything in the Top Of Descent section, it told me to start from a certain distance with a 3-degree angle and descend, I started to descend at that distance but I was much higher than the altitude I needed to catch the ILS frequency. (My throttle was in climb mode) One of the things I don’t understand is the angle issue in TOD, I think it always gives a -3-degree angle by default, but I’m not sure if just selecting and pressing the altitude I specified when I’m going to descend is enough. Do I need to do something about that 3-degree angle? And if this descent problem is not related to that, why could it be?
What did the MCDU say for ALT and did you set this ALT in the AP? And did you press the ALT-button?
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The descent problem solved itself, thanks anyway. But now I can’t catch the ILS frequency. When I look at the approach chart, it says that the ILS catching altitude is 3900 feet, but when I reach 3900, the LS is clearly on, no matter how long I wait, I can’t catch the vertical and horizontal diamonds. I have no idea if I’m reading the chart wrong.
What A320 are you flying?
At the top of descent, you should have already set the altitude that you want to descend to and right click it into managed descent mode. If it’s the default Asobo A20N, you just have to hope for the best. If it’s the Fenix or Inibuilds A20N (I don’t know about FBW), there will be a green dot on the altitude scale that tells you whether you are above or below the path. If it slips below, get the speed brakes out to help it out
For ILS capture, enable LS when below 10000ft. Then press APPR when on final. The purple triangle on the altitude scale should be above the centreline. If it is below, you are too high and it will never capture. Also chck the RAD NAV page on the MCDU to make sure that IMEN/110.30 is displayed
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What airplane are trying to fly? Remember if you are trying to intercept the glideslope from higher altitude then one prescribed then you will run into problems - can be done but requires effective energy management.
You can use 3 degree rule of thumb to make an estimate to see where you are compared to what VNAV is trying to achieve, It is good practise and IRL crews use this to stay on profile. Use 300ft per NM or loose 300ft for every 1 NM you fly. If you are flying at 30000ft then with above rule of thumb you start your decent at 100NM assuming the airport is at sea level. In your case above to reach 3900ft platform altitude from 30000ft - You initiate your decent in about 90NM, again this is approximate so you do have to take wind/QNH into consideration.
I use FBW a320, I do almost exactly what you said, but after the last turn, the plane cannot catch the vertical diamonds even though I am at the height specified in the chart on the ILS line. Is it enough to activate the LS button and wait for it to catch the vertical and horizontal ones, or should I also activate Approach and Localizer together with LS? In the videos I watched, it tells me to press the approach button when the vertical diamond is caught, and the localizer button when the horizontal diamond is caught, but after the last turn, I cannot catch the vertical diamond.
What should I do if the purple triangle is below the centerline?
This basically means you are high on profile and you need increase your rate of decent. The VNAV in FBW is sometimes wonky - it does work properly but there are times when it will bring you in high and fast, this is where you will need to intervene.
You can press the APPR button any time and it will arm LOC and G/S in blue. These won’t become active in green and replace NAV and ALT until the purple diamonds are central
However when I look closer at this chart I see what your problem is. I’m guessing that you are flying in from IMR at 130 degrees and then turning to line up with the runway? The correct procedure is to fly 130 degrees from IMR and intercept the hold pattern on ME at 163 degrees. You fly out at 163 for around 2.5 minutes after passing ME and then make your turn onto final. You should be lined up on final and intercepting the glide slope at D12.0. You are probably still at 3900ft at 3 or 4 miles out if making the turn straight from the 130 degrees to final
Correct path in red - your path in blue?
Yes, I was entering from the red path exactly as you said. So is that the problem? Should I choose this approach instead of the ILS W 34 approach?
There isnt really a “correct” approach specified here on these charts. The STAR (Standard Terminal Arrival Route) doesnt end on the localizer but on the IMR VOR. So theres no “correct” predefined way to make it to the ILS. Commercial IFR flights at such airports will usually get vectored by ATC with clear instructions. If you fly without ATC, you can just vector yourself, kinda. Look at this flight, he got vectored on the ILS.
Same for this flight today approaching from east, directly verctored onto the ILS glideslope:
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The problem is that when I enter the Arrival airport LTBJ ILS Z 34R in the Flight Plan, there is a blank space between the IMR and the approach line as in this image. How can I make an approach like in the image?
Delete IMR from the plan and you’ll get an approach far closer to the second one posted by HXArdito above
I think it’s done, right? I understand that when you fly with real ATC, he wants me to do it, but since I fly without ATC, I can arrange it myself. I guess all I have to do now is get to 3900 feet when I get to the CF34Z. Thanks everyone for your help.
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That’s the one. Should work fine for you. In a lot of real world cases, chart routings are for if you have lost comms so that you can fly a predictable route and ATC can easily figure out your intentions to keep other aircraft out of your way. Got to take approaches with a slight pinch of salt and do some of your own navigating in the sim
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Absolutely correct. First, check your charts way before you start the approach, see in the FMC if there are discontinuities and if so, check why and fix them.
At an approach like this, there is no specified path after IMR, so the plane doesnt know where to go automatically, so you have to reprogram the route, for example by deleting waypoints, to get something that makes more sense.
IRL, as you see on flightradar, usually aircraft get vectored to a direct ILS intercept instead of going around the airport for no reason.
As you say, if no ATC, you are your own ATC and basically you can get to the ILS however you want… 
he doesnt want you to do it, he would say something like “expect radio vectors to ILS 34R”. That means he will later on tell you “turn right heading 320, descent 4000ft, cleared ILS 34R” or similar, depending on from which direction you are coming etc…
At this point you are cleared for the ILS and after turning onto the localiser, you are cleared to intercept it, hit the APPR button and glide down on the slope.
You will then get the “wind 360 5knots, cleared to land ILS 34R” (or whatever the current wind is)
Many airports will not make you fly the whole published procedure, they will probably shortcut you or vector directly to the Approach.
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Thank you so much, I really got this thing figured out in my head.
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