How to use the ILS (Instrument Landing System)

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Hi all, This topic seems to pop up every so often (such as twice today for me) on how to use the ILS so I'm going to do a small tutorial! Here are some steps you should follow to use the ILS for landing, for this example I've took off from Birmingham to land back at Birmingham with an ILS approach to runway 33. 1. Right if you have an IFR flight plan when your approaching your destination airport ATC will give you approach instructions and tell you which runway you've been assigned as shown below. http://img.photobucket.com/albums/v699/future_pilot17/ILS%20Tutorial/ILS1.jpg 2. Next step is to find out what the ILS frequency is for Runway 33, to do this first press the Alt button on your keyboard and then click World. http://img.photobucket.com/albums/v699/future_pilot17/ILS%20Tutorial/ILS2.jpg And scroll down to Map. http://img.photobucket.com/albums/v699/future_pilot17/ILS%20Tutorial/ILS3.jpg 3. Now you'll get a display like the one below. http://img.photobucket.com/albums/v699/future_pilot17/ILS%20Tutorial/ILS4.jpg Move your cursor/arrow over the +/- symbols at the top to zoom in and out and move the cursor to the edge of the map to move left/right/up/down. Now if you double click on Birmingham (EGBB) you'll get a box like the one below pop up, scroll down if need be and you can clearly see there all the information needed for Runway 33 including the ILS frequency. http://img.photobucket.com/albums/v699/future_pilot17/ILS%20Tutorial/ILS5.jpg You can also get this information quicker by 'hovering' your mouse over the green ILS feather and it will give you the ILS frequency also. http://img.photobucket.com/albums/v699/future_pilot17/ILS%20Tutorial/ILS6.jpg 7. Right now you've got the frequency noted down as 110.10 you'll need to put it into your NAV1 radio. Firstly you'll have to bring up your Radio Stack, you can do this by clicking on the icon on your aircraft panel. http://img.photobucket.com/albums/v699/future_pilot17/ILS%20Tutorial/ILS7.jpg Right now you'll get your Radio Stack come up like below. http://img.photobucket.com/albums/v699/future_pilot17/ILS%20Tutorial/ILS8.jpg To change the frequency all you have to do is move your cursor over the STBY frequency in the NAV1 section and change it to 110.10. http://img.photobucket.com/albums/v699/future_pilot17/ILS%20Tutorial/ILS9.jpg Then click the small arrow thing in the middle to switch that frequency to the ACTIVE side, once that's you have to click the button on the bottom of the radio stack to activate the NAV1 radio. See below. http://img.photobucket.com/albums/v699/future_pilot17/ILS%20Tutorial/ILS10.jpg Right that's that done you can get rid of the radio stack, now just follow ATC's directions untill they tell you to intercept the ILS in a box that should look like this. http://img.photobucket.com/albums/v699/future_pilot17/ILS%20Tutorial/ILS11.jpg Obviously obey the instructions and then you have to click the APP button on the panel which is located on the Autopilot section. http://img.photobucket.com/albums/v699/future_pilot17/ILS%20Tutorial/ILS12.jpg Right now all you have to do is wait for your aircraft to intercept the ILS and when it does it'll have a mind of it's own and make a turn towards the runway, all you obviously have to do is manage the speed/flaps etc etc you'll soon see the Altitude button on the Autopilot panel switch off and the aircraft will gently glide down to the runway. Assuming your controlling everything else like the speed and whatnot! Right I think that's it, I've gone through the process I use for the ILS and I've explained every part of it so I hope you don't find it too complicated to follow and one last thing... Happy landings! :D Tom
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Profile picture for user philgatwick05

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Thanks - I'll go and refine my technique with this in mind!
Profile picture for user T5

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A really useful thread, though I should add that airspeed shouldn't exceed 250 knots below 10,000ft - someone looks a little overspeed ;)
Profile picture for user Future Pilot

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A really useful thread, though I should add that airspeed shouldn't exceed 250 knots below 10,000ft - someone looks a little overspeed
Im well aware Michael! but I was typing and trying to get decent screenshots at the same time and wasn't paying much attention to the actual flying :D.
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Has anyone got any advice on flap deployment on approach - eg when and how much?
Profile picture for user Deano

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Phil try this for the 737 Flap 1 215kts Flap 5 203kts Flap 10 191kts Flap 15 174kts Gear Down 160kts Flap 20 157kts Flap 30 148kts Flap 40 140kts Edited to say these come from an ex Virgin-Blue 737 Captain ( I think I got the flap degrees right as this was from memory)
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Right I think that's it, I've gone through the process I use for the ILS and I've explained every part of it
One of the most important things here is actually understanding what is happening, the ILS consists of a Localiser which basically is your runway centreline, but not always, this can be offset like the approach into Innsbruck rwy26, and your glideslope which is typically your descent path down the ILS, a normal glideslope will be a 3 degree approach angle, to obtain your 3 degrees and remain on it a simple formula can be used, this is ROD (Rate Of Descent) = 5 x groundspeed, so for a groundspeed of 140kts you need a rate of descent of 700fpm, remember this is groundspeed and not necessarily your IAS as shown on your ASI. It is very very important when conducting an ILS approach to have the correct OBI setting on your HSI, for the approach stated above this will be set to 330 degrees, on your MCP for your particular aircraft this will be indicated by the course, just set this to 330, the 330 is the actual QDM of the runway. It is imperative on an automated ILS approach as stated above that you intercept the glideslope from below it, you will not capture it from above, on your PFD & HSI you will see a white dot to the left of the window, this should be towards the top of the little screen, this indicates you are below the GS which is ok, if you fly level you will intercept it, if you are descending equal to or more than the ROD in the formula I gave you will never intercept it and will stay too low, next thing is the Localiser deviation, this is shown on the PFD & HSI by a white dot at the bottom of the screen, and also on the HSI by a CDI or course deviation indicator, this is where it is important you set the correct runway QDM into the course selector on the MCP, basically the course deviation indicator will show the localiser and hence the runway centreline in relation to yourself, if the needle is left then fly left, if it is right then fly right, you will know you are on the LLZ & GS because the 2 white dots will be centralised, you should see a scale as well dipicted as yellow dots? (may vary), well if the white dots hit 1 dot deviation this constitutes a go around and missed approach procedure, which I'm sure you all do right? ;) I'll add more later Dean
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Cheers Deano up to now I've always guessed it!!
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Thanks Tom :D:D
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Then click the small arrow thing in the middle to switch that frequency to the ACTIVE side, once that's you have to click the button on the bottom of the radio stack to activate the NAV1 radio. See below. http://img.photobucket.com/albums/v699/future_pilot17/ILS%20Tutorial/ILS10.jpg
Tom Not trying to hijack what you are doing, but merely trying to make sure the procedures are right for more enjoyment, this button at the bottom of the radio stack is only used to IDENT the freq selected, it does not activate it, as you can see from this picture you posted http://img.photobucket.com/albums/v699/future_pilot17/ILS%20Tutorial/ILS5.jpg The ILS identifier for rwy 33 is IBM, so when you tune the freq (or any nav aid freq for that matter) you need to ident it with the button you said to make sure you are picking up the right one, after hitting that button you should hear the morse ident for IBM which will be . . (I) - . . . (B) - - (M) Dean
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Tom Not trying to hijack what you are doing, but merely trying to make sure the procedures are right for more enjoyment
Of course not Dean :) , thanks for providing more information on the subject. I've certainly learned a few more things from the posts you contributed :cool: .
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Dean - u sure about flaps 40 on a 737? I thought they never really deployed them to that extent?
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Dean - u sure about flaps 40 on a 737? I thought they never really deployed them to that extent?
Correct me if I'm wrong people but I always thought Flaps 40 was only ever used if the runway the B737 is landing on is very short or there is limited landing distance?
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Not sure Chris to be honest, like i said, the degrees were from memory because I did not write down what he said, when I see him next I'll ask him :) I guess what he may have been saying is that when they DO use them that is around the speed that it is deployed

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Excellent info here. Thanks Tom (and others). Any chance of making this tread "Sticky", so we can easily find it again later? Maybe a "Flying Tips" subforum?
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YAY! Your guide works Tom...very good :D:D
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if it starts to disappear towards the bottom I'll sticky it :)
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Great tutorial, Ive always wondered how the ILS works! Thanks a lot Tom!

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Ta very much Tom - just made probably my best landing to date in an EZY B737 from Liverpool -> Newcastle ferry flight, Advice is greatly appreciated, Wozza
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Wow I'm quite overwhelmed by the replies, glad you found it useful everybody :D.