Originally Posted by
Plastic Bug
The restriction regarding CAT II/III doesn't completely lie with the aircraft, it lies with the airfield as well. When an airfield is conducting CAT II/III ops, there are certain requirements that have to be met, protecting the ILS beam etc and it's all in the JEPP.
PB
The JAR seems to suggest that some Cat 1 ILS installations are NOT suitable for autolands. I take this to mean that there is something inherent to the particular installation from whence this restriction derives its origin, rather than because it hasn't been "protected" during such an approach.
Which begs the question, "Why?"
Maybe in some way the ILS beam characteristics don't comply with EUROCAE ED-46/47 or other appropriate certification documents?
I was aware that we're talking about an a/c system functionality check but not knowing
exactly how the autoland system works, I was not sure whether the a/c can distinguish between a Cat 1 ILS signal and a Cat 3 ILS signal.
For certification ACJ AWO 131 talks about flight demonstration for autoland and acceptable means of compliance. It involves (as I understand) up to 100 approaches during which time various flight parameters are monitored.
It seems emminently reasonable to assume that these would be to Cat 2/3 installations.
I just find it strange that a temporarily de-graded a/c can be returned to full Cat 2/3 autoland status on the basis of a "standard landing" to a Cat 1 facility...
You'd never have got it certified in the first place if you did that (because I hazard a guess many of your deviations would be out of limits), but there seems to be the presumption that if an a/c can do an autoland using a Cat 1 facility, it could easily do one to a Cat 2/3 facility.
Maybe this assumption is justified knowing how the a/c uses the respective ILS signals, but not having access to that information, I was curious to know whether the above inference is a non sequiter....
Curiously.