ILS/APPR Help

Hello All.

I’m having a couple of issues, definitely caused by me, relating to an ILS approach.

What sort of altitude should you intercept an ILS at? Currently I try and intercept at around 3000 feet MSL, which works great on the larger airports like Paris and Heathrow, but not so great on smaller airports like London City or Edinburgh for example. Does the altitude I attempt to intercept the ILS at need to change depending on the Airport? And does Airport class have anything to do with this?

Furthermore, I am also finding that the aircraft sometimes approaches with a left or right hand side bias, which is very annoying when touching down as I instantly have to correct it with the rudder, and I can’t imagine it is very realistic to do that.

Any help with these questions would be hugely appreciated!
Thanks!

Hi and welcome to the community…
why not check out these two posts below…

Happy Flying & Good Luck :D
Cign

London City airport is an anomaly that does not have a 3 degree approach due to high buildings next to the airport!

Hey! Check out the ILS approach charts for your airport at www.ifatc.org or www.airnav.com or simply search “ABCD Approach Charts” on Google (ABCD being any airport’s ICAO code). You’ll find all the altitudes you need there.

Here’s a good tutorial on how to read an approach chart.

Hello!

3000MSL its a normal intercept altitude for airports with minimal elevation: Unfortunately, lets imagine an airport like KDEN (Denver) with an elevation of 5’430 ft, if you try to intercept at 3’000 ft you will crash into the ground.

Normally on IF, the glideslope at the end of the cone is placed at 3’000ft AAL (Above Airport Elevation). That means that at EGLL, it would be located at 3’083 ft MSL (3’000ft + Airport elevation) but at KEDN would be at 8’430ft MSL

You see that’s a huge difference between intercept altitudes, and you should be aware of this, remember the formula to obtain MSL altitude for the intercept is MSL = Airport elevation + 3’000ft

Another way for knowing your intercept altitude is by following real word ILS Approach charts, where the altitudes are shown in MSL

FlightAware_DEN_IAP_ILS RWY 34L (CAT II - III)
Source
Here you have for example the ILS Chart for runway 34L at Denver:
You see that you should start on KAIHR at 10’000ft and start descending at MERKL,be on RNOLD at 9’000ft and properly intercept the GS at the end of the cone at approximately 8’400ft MSL

I let you here a more in-depth tutorial of how to understand an appr chart

Cheers!

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Just adding to what you asked about the aircraft having a far left/right bias when landing and having to correct it with the rudder. This is completely fine, normal, and done in the real world. This is caused by a crosswind, which is when the wind isn’t coming directly towards your aircraft. This will cause your nose to turn towards the wind, which is fine as long as you correct with rudder right before you touch down to straighten out! Try applying the rudder already when you start your flair to ensure you won’t have to do it after your touchdown!

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