Hi Fuji
Originally Posted by Fuji Abound
I would also be interested in the specific reference to the G/S FM immune requirement for approaches outside controlled airspace.
I'm not sure what you mean by this; if you want to see a reference to ILS approaches outside controlled airspace, I have given one back on page 2 although it's up to each of us to decide on its relevance.
If you specifically mean a reference to the FM Immunity (or lack thereof) of glideslope receivers, then I suspect you'll never find one. Glideslopes work on UHF and therefore are not susceptible to FM interference. It is the VHF localiser which is, if only in theory.
Hello Homeguard
It's interesting that you mention the LA Class 1 and Class 3 approvals. I spoke with an engineer I know last year and had been led to believe, perhaps wrongly, that these classifications of kit can be somewhat bogus under the JAR/EASA schema. Perhaps I had misunderstood what he was saying.
This page and
this one both hint that these definitions might not be entirely relevant to aircraft issued with CofA's by EASA, for example. Specifically, from the former page;
With effect from 28 September 2003, for the purposes of new certifications [of avionics equipment], BCAR Section R is applicable as a requirement only to those aircraft which are excluded from the coverage of Regulation (EC) No. 1592/2002. For a definition of these aircraft, see CAP 455 Airworthiness Notice No. 1.
Needless to say that most club/school spam-cans are indeed covered by EC1592/2002. Permit aircraft and some older rarities are not.
From the second source;
Volumes 1 and 2 of CAP 208 - Aircraft Radio Equipment, are now considered to be obsolescent in that these volumes no longer represent current minimum performance requirements or complete and definitive records of aircraft radio equipment approved by CAA. Volume 1 of CAP 208, listed certain ICAO standards (for example, ICAO annex 10 requires VHF communication transceivers to have a frequency stability operation of plus or minus 0.003%), whcih have been superseded by later requirements.
If the CAA themselves are suggesting that their own requirements have been 'superceded', is it not possible that this may have occurred in the ORS that states avionics equipment must be FM Immune (i.e. equivalent to LA Class I) in order to fly an ILS approach inside or outside controlled airspace?
I ask this as a genuine question. If the Class I/Class III distinctions are still valid and meaningful for
all UK registered aircraft then fair play. But if they are only meaningful for those aicraft still maintained under national airworthiness rules (as opposed to JAA/EASA) then it muddies the water a bit.
All a bit of a mess really.