Are CATIII Autolands runway dependent?

[Fabo 213]

However

- OP is trying for CAT III, *usually* a fail-op capable aircraft,

 

Not true, fail-op option is comparatively rare in an NG, and airplanes with fail-passive option are fully capable of (CAT IIIa) automatic landing, only without rollout. To say one has to have fail-op option for autoland to work is therefore in essence a lie, whether intentional or misguided, and damaging to community as a whole in it's understanding of operation. It's the same kind of thing like when people started claiming all of a sudden that using a low CI is a universal remedy for descend problems, while that might only mitigate the symptoms (if even that) of the root problem - improper descent planning.

 

 

 

- OP is using the HGS (usually buys lower minima for other approach types)

 

While true, it is irrelevant, as any HUGS setting does not have any bearing on AFDS behaviour; as such a red herring that should not be discussed while troubleshooting a different system (only adds confusion).

Besides, the lower minima from HUGS only happen for hand-flown approaches anyway, no bearing on automatic landing.

 

- Second a/p engagement is down to SOP. A company manual might have a 'engage before xxxxft'.

 

That is true, but it does have to happen between APP mode engagement and the point where self-check begins -it's therefore important for troubleshooting to ensure that second AP connection is happening consistently before the selfchecks would begin.

[Budbud 227]

 

 

Copper., on 08 Jan 2016 - 06:45 AM, said:

However
- OP is trying for CAT III, *usually* a fail-op capable aircraft,
 
Not true, fail-op option is comparatively rare in an NG, and airplanes with fail-passive option are fully capable of (CAT IIIa) automatic landing, only without rollout. To say one has to have fail-op option for autoland to work is therefore in essence a lie, whether intentional or misguided, and damaging to community as a whole in it's understanding of operation. It's the same kind of thing like when people started claiming all of a sudden that using a low CI is a universal remedy for descend problems, while that might only mitigate the symptoms (if even that) of the root problem - improper descent planning.

 

 

 

After following those steps, most of my landings are still single channel.  I should be seeing CMD followed by land3 at 1500 AGL.  The only thing I can think of is that the PMDG FMS somehow knows which runways are CATIII equipped and which are not?

 

The thing is that the OP was looking for the land 3 indication on the PFD which is - correct me if I'm wrong - only displayed on a fail operational autoland certified aircraft while a fail passive will still be certified for autoland but "only" land 2.

 

I think that there is a large confusion regarding autoland, ILS catII/catIII, fail operational/fail passive, land2/land3... The distinction between the approach type (ILS catII/catIII) and the aircraft autoland capability (land2/land3) seems to be blurry for a lot of people. And especially what can be done with what equipement (whether ground based or on board the aircraft).

 

The question of ILS / autoland is quite recurrent on the forum.

[Fabo 213]

 

 

The thing is that the OP was looking for the land 3 indication on the PFD which is - correct me if I'm wrong - only displayed on a fail operational autoland certified aircraft while a fail passive will still be certified for autoland but "only" land 2.

 

Fair enough, although the green/amber indications, while worded differently, are functionally practically identical.

 

It was, however, stated in this thread:
 

 

 

Typically, at least 3 things need to be certified capable before you can conduct Autoland ops 

 

...

- Make sure the airplane autopilot is Fail - Operational.

which is not true, and that is what I objected to.

 

 

 

I think that there is a large confusion regarding autoland, ILS catII/catIII, fail operational/fail passive, land2/land3... The distinction between the approach type (ILS catII/catIII) and the aircraft autoland capability (land2/land3) seems to be blurry for a lot of people. And especially what can be done with what equipement (whether ground based or on board the aircraft).

 

Agreed.

[Copper. 78]

Since you're here to nit pick...

 

I don't remember saying fail op is required for autoland. My airline have fail passive but still conduct autoland ops to CAT II minima when required, what I did say was that HGS buys lower minima FOR OTHER APPROACH TYPES... or did you choose to ignore that?!

 

The '3 things' statement was proffered generally, the following three suggestions were case specific.

[scandinavian13 5,192]

I think that there is a large confusion regarding autoland, ILS catII/catIII, fail operational/fail passive, land2/land3... The distinction between the approach type (ILS catII/catIII) and the aircraft autoland capability (land2/land3) seems to be blurry for a lot of people. And especially what can be done with what equipement (whether ground based or on board the aircraft).

 

Unfortunately it is a somewhat complex topic, but at the same time, I'd argue that a lot of the confusion comes from people with sophomoric knowledge (spoken generally here - I haven't paid much attention to what's going on in this thread, specifically) jumping into these discussions and throwing their knowledge out there without any disclaimers. If you look out in real and sim forums alike, you'll see people speaking from supposed positions of knowledge not only telling people "how it is," but debating people who are actually describing it correctly (don't take this to mean that I have never done this - I have, I'll admit that openly). This isn't specific to the ILS thing alone; it covers quite a few topics. At the same time, I think we can all cut out a lot of the misunderstanding by avoiding the use of "ILS landing" and "CATIII Autoland." Both of those put off that the terms are linked. ILS with autoland somewhat implies that an ILS always ends in an autoland (and that autoland is the 'norm'). Even if you know that it does not, you might be surprised at how many don't know this. Additionally autoland could theoretically be used with RNAV - it's just not currently designed to use the cues provided by RNAV, nor is it approved for that yet. The latter "CATIII Autoland" implies that autoland is dependent on CATIII facilities, and it's not. As I always like to point out: the LOC and GS antennas are usually the same for a CATI and CATIII installation. The difference is mainly assurance of signal reception and quality, backup power, and a bunch of pencil whipping.

 

The more people who study up and go read primary sources, the more knowledgeable the community will be, and the less confusion circles around. As a pilot myself, I cringe every time I hear "well my friend is a pilot for XYZ Airlines and he said..." mostly because not everyone is an expert. Think about it. Take any single person and look at their knowledge of their job - any job. Are they perfectly knowledgeable about their job, and how their job interacts with other people's jobs? I'd argue that the average worker has quite a few knowledge gaps about fringe issues (in our realm: the intricacies of an ILS array and how they get certified), specific legalities (interpreting regs), and job roles they interact with (pilots interactions with ATC). I'm not saying people don't know how to do their jobs - I'm simply saying your average person is average. Pilots are people too, and your average person doesn't care enough to know everything. As such, even if you heard it from your best pilot or ATC buddy, it's best to verify before repeating it.

[Fabo 213]

 

 

I don't remember saying fail op is required for autoland. My airline have fail passive but still conduct autoland ops to CAT II minima when required, what I did say was that HGS buys lower minima FOR OTHER APPROACH TYPES... or did you choose to ignore that?!

 

I didn't choose to ignore that - I very specifically said it's irrelevant, since AFDS is totally independent from HUGS and therefore HUGS is in no way related to the problem described; and need not be discussed here.

 

 

 

The '3 things' statement was proffered generally, the following three suggestions were case specific.

 

I appologize if it was your intention to separate the ideas, but it didn't came out that way - to me it seemed like you were saying the airplane needs to have Fail Op to do an automatic landing.