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trazee
08-26-2008, 03:36 AM
1.guys, in ILS landing we are going to consider the ILS frequency of the destination airport and enter it on the NAV radio, how about the heading? when are we going to use the heading(destination airport/runway), i have tried a couple of flights using ILS during landings but i havent remembered entering the heading but still it was a succesfull landing, what is the use of the HEADING and when are we going to use it during the course of our navigation?

2. on the control panel there is a knob labeled CRS usually beside the heading knob? i havent tried using it during flights but i was able to reach my destination by just following ATC routings, is it necessary?

tigisfat
08-26-2008, 05:32 AM
The course knob (or CRS) is where you need to enter the ILS heading. If you go to the map screen and click on your destination airport, there will be a list of runways, their ILS frequencies, and proper headings to enter un 'CRS'. It will be a more precise heading than just using the runway number. From there, you need to make sure NAV/GPS is in NAV, and you can fly it yourself or have APP hold on your autopilot do all the work.

You can also click on the green ILS feathers on the map screen and it will give you the proper information.


Did this answer your question? if not, let me know!!

trazee
08-27-2008, 10:12 AM
@tigisfat,
sir, i tried entering the runway heading of my destination airport and during approach (final) i noticed that the plane is not actually lined up with the runway, it is much more reliable to use the ILS then APP...do i miss something? why the plane will not align with the runway

RyanbATC
08-27-2008, 05:30 PM
The ILS heading can be different than the number that is printed in white on the runway. Sometimes the ILS course is 5 or more degrees off.

Pull up the map in FSX by going to World->Map Click on the airport you're landing at and open the airport option and find the runway you want to land on and read the ILS HDG The ILS heading is what you want to dial in for your course or OBS.

However, some ILS' are also not aligned with the runway, on purpose. There may be terrain or something in the way of the straight-in landing path. So they offset it...

Out of curiosity, what is the airport and runway you wish to land on?

EDIT: I'm adding a screenshot here... I've got this fancy shmancy glass cockpit but it's still the same thing. Make sure your GPS/NAV switch is set to VLOC or VOR or NAV etc, and NOT GPS mode. The Runway I'm landing on is Ry27 at Duluth, KDLH. The ILS heading (course I say) is 271 degrees. Not far off the runway number of 27 (270 degrees). You want the needle to center up so there is a solid green line (in this cockpit, may be yellow or other colors) from the top of the arrow to the end. Then you turn your acft to keep it centered. The 2nd pic is me on short final. At duluth the PAPI's (4 lights left side of RY) aren't aligned with the ILS glideslope for some reason, that's why it appears I'm high. But I'm on the glideslope. And though not perfect I am on the localizer (the green line is mostly one solid line though you can tell it's not a perfect straight line, so I'm a little off, the wind was all over the place hehe :)
http://i141.photobucket.com/albums/r43/ryanbatc/obs271.jpg

http://i141.photobucket.com/albums/r43/ryanbatc/obs271land.jpg

trazee
09-02-2008, 02:27 AM
when you approach for final mainly relying on the ILS heading, but when you actually see that its a bit offset from the runway (since not all ILS headings are perfectly aligned due to some reasons) what should i do? make visual adjustments to line up or re-adjust heading making it identical with the runway markings?

what is the interpretation of the 4 lights on the runway as you approach it changes colors fro time to time as you get near the tip of the runway?

deepsea345
09-02-2008, 03:50 AM
when you approach for final mainly relying on the ILS heading, but when you actually see that its a bit offset from the runway (since not all ILS headings are perfectly aligned due to some reasons) what should i do? make visual adjustments to line up or re-adjust heading making it identical with the runway markings?

what is the interpretation of the 4 lights on the runway as you approach it changes colors fro time to time as you get near the tip of the runway?

the four lights is the Precision Approach Path Indicator (PAPI), it tells you if you are on the glideslope

white white/red red = good (on the G/S)

White white/white red = high

all white = too high

white red/red red =low

all red = too low

there are also other types which have a different amount or position of lights (VASI, etc...)

tailwindflyer
12-17-2008, 03:16 PM
1.guys, in ILS landing we are going to consider the ILS frequency of the destination airport and enter it on the NAV radio, how about the heading? when are we going to use the heading(destination airport/runway), i have tried a couple of flights using ILS during landings but i havent remembered entering the heading but still it was a succesfull landing, what is the use of the HEADING and when are we going to use it during the course of our navigation?

To get the correct final approach course heading you will need to find it on an IAP (instrument approach plate). They rarely will be the same number as the runway since the runway numbers are in 10deg increments and do not line up perfectly with the final approach course. When you enter an ILS frequency in your NAV radio, the OBS will have no effect on where the needles point. Pilots on an instrument approach usually dial in the final course as a reminder only. The needles are now slaved to the LOC and GS signals coming from the instrument landing system on the field. Think of these needles as being where you want to go. If the vertical needle is two dots to the right of center, you would turn slightly to the right to bring it back to center. If the horizontal needle is below the center dot then you are high and need to come down. The goal is to keep both needles centered. For entering a heading, what are you entering it in? If you are using the autopilot then it should be in approach mode and picking up its navigation from the ILS system. If you are putting it on the heading bug then it is meaningless since that is either a reference mark or what the AP is taking its steering commands from....but your AP should be in approach mode. Setting the OBS on the CDI doesn't do anything because it is taking its guidance from the LOC & GS from the ILS.

mgh
12-17-2008, 05:08 PM
when you approach for final mainly relying on the ILS heading, but when you actually see that its a bit offset from the runway (since not all ILS headings are perfectly aligned due to some reasons) what should i do? make visual adjustments to line up or re-adjust heading making it identical with the runway markings?

what is the interpretation of the 4 lights on the runway as you approach it changes colors fro time to time as you get near the tip of the runway?

If the localiser is offset the real world approach plates will normally have a statement like "localiser intercepts runway centre line at ...". Generally you follow the localiser then make an appropriate change in heading at the intersection.