View Full Version : ILS Jeppesen.

3rd Mar 2008, 03:20
There used to be a good diagram in the Jeppesen Manuals depicting the range and the number of degrees either side of the LLZ that you could expect to receive accurate ILS signals. It appears this has been removed. Would anybody have a copy of that diagram? if so, could you please post it to me.



3rd Mar 2008, 20:17
It's a bit of a mess these days as the required service volumes have been changed from what they used to be - and not in the same way across the board. In the US, they have introduced smaller service volumes in order to cater for the number of installations which can be present in a given area. In other places, the clearance sector has been reduced or even removed alltogether (I think this became reality but am not 100% certain) as the precision of the means to becoming established on the LLZ has increased.

That's probably the answer to why it is no longer in Jeppesen.

I do not have the picture in a digital format, but it used to be 25 nm within 10 degrees off the course line and 17 nm within 35 degrees.

I think the new US specification is for 10 nm in the clearance sector. Can't recall the range requirement for the +/- 10 degrees sector.

Should give you more to google on if it doesn't help in any other way.


Dream Land
4th Mar 2008, 09:53
Don't have a book handy, I seem to remember a pretty good diagram in the AIM. Good luck.

Pilot Pete
4th Mar 2008, 09:58
This any use? http://www.hkatc.gov.hk/HK_AIP/aic/AIC%2004-06.pdf

It would appear to come from ICAO Annex 10 Vol 1....which incidentally you can buy from ICAO publications for the pittance that is $1200, but of course you would get to read all the other Annexies (?) all year long for that fee. My, how the cold winter would pass so quickly.....:ok:


4th Mar 2008, 20:37

Here you can read all the ICAO annexes for free:

http://dcaa.slv.dk: 8000/icaodocs/

It's the Danish CAA, who provides this service. :)


5th Mar 2008, 01:02
Ah great link Coldbear! :}

The "10 degrees either side of the centre line within 25NM and 35 degrees within 17NM" is what we learnt for the ATPL exams, though I guess this can be varied by individual authorities although my understanding is that they can only make it MORE restrictive, never less so.