Recently I’ve been having trouble landing via ILS/auto land. Previously I’ve had no issues using it to land the aircraft but literally my last four attempts have all failed to capture the GS and Localiser. I’ve done nothing different (as far as I can tell) to previous attempts. I’ve hit the Les button around 15/20nm out, it brings up the vertical and lateral four white dots and I wait for the magenta diamonds to line up but they don’t even appear…
I was advised that I need to check to make sure the runways frequency is loaded in the RADNAV page (it said ILS27/ 111.70) for Farnborough and still it didn’t work as intended.
Can anyone shed some light as to what is happening, am I at fault, is it a bug…?
The frequency isn’t necessarily correct when autotuned.
You should check the correct frequency during your preflight planning on the world map.
(You have to enable the navaids in the filter)
Oh right, ok, so what I’m talking about is just an ILS landing, not auto land…? Tbf, in the right conditions I’ve been able to land without touching the controls at all, maybe that’s why I mentioned auto land. Thanks anyway.
My issue isn’t what is or isn’t an “auto land”. My issue is, when trying to land using the ILS the aircraft wasn’t capturing the LOC or G/S when previously I had been able to do it most times successfully when not doing anything differently.
It does. Are you at the right altitude for the capture as displayed on the approach charts for that runway? This will be different for every airport and every individual runway, so using a universal value (I see many people say “you capture the glide slope at 3000’) is incorrect and misleading - you must be at the proper intercept altitude for that specific runway. In many cases it’s around that range, but it can also be a much higher or lower intercept point. It’s essential to check the intercept altitude for that specific runway - even at the same airport, different runways can and do have different intercept altitudes. If you are too high or too low you’ll miss, even with the correct frequency entered. Unfortunately if you’re using the default sim flight planner, often times the glideslope waypoints don’t have the proper altitude indicated on the MCDU, so it’s important to refer to charts in my opinion as sometimes the altitude is far enough off to miss the intercept entirely.
Also, to see the ILS runway info on the PFD & ND as well as the pink diamonds, you need to make sure you have the LS button engaged (on/green).
To be fair, most of the time when 3000ft as an intercept altitude is being mentioned, 10NM are mentioned as well. In that case 3000ft is correct for all ILS approaches with a 3° GS.
Furthermore the LOC indication isn’t affected by the altitude.
There isn’t a “proper intercept altitude for a specific runway”, at least not for a nominal 3 degree glidepath. If you wish to intercept the GS higher, you simply need to start further out to intercept the glideslope from below, 3 nm per 1000 ft above aerodrome level in a good rule of thumb. To reduce noise pollution and save fuel, aircraft usually aim a continuous descent approach nowadays anyway, meaning flying a 3 degree path all the way down, this way there isn’t really an level-off segment at intercept altitude, the aircraft is already on glideslope (and localizer) when rolling out on final.
Ah. I just go based on approach charts which have different altitude levels to capture the glide slope. And certainly 3000’ does not apply at every runway even those with a 3° slope because of elevation differences, unless AGL is what is meant but again, not exactly useful information as it’s not readily available data above 2500’.
And correct me if I’m wrong but is there not a range of the ILS equipment and beacon frequency? Surely you can’t start a 3° descent 100NM out and “capture the glideslope” there - there is a certain point and altitude that it will capture and start the slope on its own. Same thing if flying completely level and approach mode on - the slope won’t capture until within range.
I have definitely overflown the intercept point before due to being too high and seemingly out of range, which is why I bring all this up. The approach charts for different runways do in fact specify different altitudes to be at to effectively intercept the glideslope. There would be no need if it was “always 3000’” and ten NM out. That, and not every runway has a straight final for ten NM or longer.
The approach charts also show the range of the beacon…
