Beyond VNKT......yes, indeed???
 

7478ti I have heard that "drone drivers", sitting in their air conditioned connexes, are putting them in an alarming rate - but that maybe another argument/thread for another day.

Automation dependency and complacency will always be a factor which can not be ignored. Then there are the "knowledge" and "experience" factors that are required so that you now what is doing and what it has to do next, thus actively "monitoring" the FMA changes, speeds, decent rates and distances to which where derived from the NAV Database and how they relate to the approach chart for your category of aircraft.

In short, you have to know what it all means and how it applies and remains within legality.

Anyone can select RWY xx RNAV APP with a XXXXX TRANSITION and sit back and watch letting it fly all the way to touch down and roll out - its knowing why and for what reason at the particular airport for this runway and what to do when degradation occurs both the aircraft required systems and from the signal.

After all, this particular accident occurred after RNAV(RNP) approach with a DA(H) of 4650' with a threshold height of 4318 which will give a required visual segment of 332'. However, due to "legalities" this approach is to be conducted as a non-precision approach, so, an additional 50' has to be added to the DA(H). The resultant vertical/height minima is well above the standard CAT I to which you are expected to perform a manual landing after "breaking out" and with runway "environment" visual. In fact, it is common to fly a CAT I ILS manually.

My point is that it is necessary to understand what is going on and the "flight" is in accordance with the Company's OPS SPEC.

The posted pax video indicates that the aircraft descended into fog well after the DA(H). I hark back to the decision making process from the beginning back in Istanbul.

Believe it of not 7478ti, but out on the line, doing a basic GNSS/LNAV approach, the number of times I have said., "you're in VNAV ALT - you know that, right" and the response was "yes, I know" and then we go over the FAF and bloggs just sits there staring at the PFD - looking at what?? who knows. My intervention then is required. OR they do it when they are in VNAV SPD.:ugh:

System understanding let alone understanding VNAV is in very short supply - most don't know they are required to look at the RNP value to check it is within the required value before conducting the approach - and you want them to get their heads around GLS/GBAS?

aterpster,

You would think it was CAT D but it is not. It is classed as a CAT C aeroplane.

This accident occurred on the morning of MAR 4th, so a NOTAM effective from the 9th APR has nil bearing on the actual accident flight.

A possible cause for the issuance of the NOTAM may well be due to landing threshold pavement damage due to the "hard landing" of the accident aircraft.

Cokebottle:

A previous version of the NOTAM was effective at the time of the accident. I mentioned it in Post #29 on March 4th. Here is the NOTAM on the date of the accident:

Also, you mentioned above having to add 50 feet to the VNKT DA if I understood you correctly. It's a DA, so that must be an operator specific requirement. It would not be for a U.S. operator.

A330 IS a CAT D aircraft, I operate it!

Maybe in HKG ( Cathay ) . I previously replied to ATP on this .

http://www.airbus.com/fileadmin/medi...at-Feb2013.pdf

This suggests that the standard is in fact C , but I believe that there cat D variants . Don't assume that your Airlines Procedures or variants are the standard . Heaven forbid , a "Heavy" is CAT C .

Hope it is not a blow to the ego that that some 321's are CAT D .

How can somebody that operates a heavy jet not know which category the airplane is? :ugh:

Isn´t this related to speed above the threshold, which, should be an important speed to know? At least as a rough guess?

Or does your company make you do flapless landings as part of the SOPs for fuel savings??? :}

aterpster:

1. NOTAM - Okay, understand now and agree (missed your #29 post). In this age of self dispatching armed only with your "flight pack" just printed off by yourself, how many pilots actually review NOTAMS and provide a NOTAM Brief to all the operating tech crew, especially when under time pressure?

2. +50' - Refer to ICAO Annex 6 Part 1, Chap 4 which deals with Aerodrome Operating Minima (AOM). Operators may determine their own AOM after considering the factors listed in Annex 6 or alternatively that can add 50' to the charted DA/MDA. This is dependent on the approach design criteria of PANS-OPS (new/old) and State Rules and Procedures which can be found in Jeppesen VOL 1.

The USA uses TERPS design criteria.

The definitions of DA and MDA (non-precision) is the main contributing factor for Company's requiring a +50' additive.

A DA is an altitude whereby a "decision" to continue or execute a missed approach must have been made - the aircraft is permitted to decent below that altitude either for the purpose of continuing the approach or in the process of executing a missed approach.

A MDA (Minimum Decent Altitude) is used for non-precision approaches and is an altitude that can only flown below if the approach is to be continued. The aircraft is not allowed to decent below this altitude when executing a missed approach.

Hence, for non-precision approaches, Company's mandate the +50' additive to ensure legal compliance in the event of a missed approach being executed.

Here are some direct copy and pastes from my Company's SOP:
iceman50:

Well congratulations and I guess you have it up on me because I don't operate it.:cool:.

I assumed "it" to be CAT D also )through ignorance) but in a previous post in this thread it was stated that THY has their A330 as CAT C. (Stone_cold has clarified this now - thanks). Hence I based my short reply on that post as that post was answering a question related to why the crew elected to do the initial approach when VIS was reported to be 1000M. Keep in mind that the initial approach resulted in a missed approach because the runway environment was not visual at the DA(H).

Being CAT D only increases the MINIMA for height and VIZ.

This debating and splitting of hairs is all great but the "elephant in the room" is still in the room gentlemen. The PIC intentionally or unknowningly (or combination of both) disregarded SOP and State Rules and Procedures for this flight.

The key word in all this is "POTENTIAL" - what was the potential for an accident. The responsibility of every pilot is to mitigate the potential for an accident. Sh@te, that is why we are there!

In this case, the potential was instigated back in Istanbul dispatch and only increased as the flight progressed because of the "decision making processes" of the flight crew.

RunSick:

Cynicism young man - Cynicism........:D

Handling Speeds are used to establish aircraft category and are set out in State AIP and Jeppesen for those who actually care enough to look.

The aircraft weight standard is Certified MLW and the resultant speeds are defined for approach segments:
1. Vat
2. IAF
3. FAF
4. Visual manoeuvring (Circling)
5. Max SPD for Missed Approach

Depends on the type of aircraft your company has. For instance, mine has the B777-200 and -300. The first is cat C , the second cat D.
So if you fly for an airline with only -300 type, you wouldn't know the -200 is a different cat.
I imagine the airbustypes have the same category differences.

@sleeper

Yes, you´re right about the category changes accoding to variants. That is the case of the A340 for example.

However, ALL A330 variants are CAT C.

Cheers.

Coke:

I have my views about the crew and NOTAMs but that isn't my point. My point is that the aviation authority with responsibility for the VNKT Rwy 2 RNP AR approach should have (still should) issue a NOTAM to not authorize the approach until the threshold work is completed. And, approach control/tower should not be using that approach until the runway is restored to the same threshold that is in the FMS database.

aterpster:

I agree with you, however, never assume that ATC (including the hapless chappie in the TWR) read NOTAMS. I can list many personal experiences.:ok:

With technical crew......need I continue?

Most of us know what happened here. It will all come out in the report. Be patient and spare the mud slinging.

Maybe the report will highlight just how confusing and unclear the regs are to normal operating pilots, and point out that those operating the aircraft need to receive clarity so we know what the fcuk we are allowed to to, and what we are not!

I'm authorized to carry out these approaches (and have had sim training) at this airport as a private operator, but now I'm confused! It would appear to be the case that my authority is confused also.

Don't think it's mudslinging .

Regardless of the type of NPA , from some point (MDA/DA) , to continue the approach ,visual contact with the runway must exist . As this was not CAT111 B NO DH ,the crew should have initiated a go-around if they lost visual contact at any time after this point .

The 3D/2D RNAV , GPS , LPV GBAS , AR etc. , the legality/requirements to commence approach , the notams , minimums are all nice discussion items , but would be probably deemed contributory . They didn't hit anything on the approach , they impacted the airport surface after supposedly being visual . Maybe they mis-identified the runway/taxi-way ? But this was in the landing / visual phase .

aterpster
 

ATC is not in a position to do that. Only the Nelaese Aviation authority can close the APP. A controller never force you to do any kind of approach, it can propose one , but up to the crew to accept or not depending on their own equipment, its qualifications and its company minima. And it that include integrating NOTAMs changes such as this one .
Just to remind you that NOTAMS are asumed to be read by the crew when contating ATC. We do not have to check, and frankly do not have time.

Also, to understand this particular case, remember this is a A330 from a large International carrier coming to a third world country, the local ATC is very unlikely to challenge a pilot decision there.

Coke:

Nonetheless, the procedure should have been NOTAMed OTS because of the displayed threshold. Then, the tech crew may have seen the NOTAM.

I think the ICAO folks wouldn't be pleased with the lack of such a NOTAM then and now. But, they advise, not control such circumstances. It could have an affect on the accident report, though.

ATC Watcher:

I understand what you are saying, but when an approach is NOTAMed OTS because of a runway problem, then local ATC should be briefed to not use the approach for safety reasons, sort of like a closed runway.

At KLAX, for example, when they had a long term project to reconfigure the taxiways to accept the A380, the construction equipment didn't close 25R but it render the ILS unusable for months. Approach control knew this and cleared aircraft for the RNAV approach or if the crew couldn't do RNAV, they were assigned a different runway with a useable ILS.

Of course, this is academic at VNKT, the approach wasn't (and isn't) NOTAMed OTS.

Most of us know what happened? Well not all of us know. How about telling us as a report may not be out for two years and in that time, some of us that don't know what happened could encounter the same situation.

Help prevent a repeat accident by telling us what happened. By not doing so, you could be one of the holes in the Swiss cheese if it happens again.

aterpster :

I agree fully , the hint was in my last sentence.
LAX is not KTM ,and the 300 USD/month local TWR controller is not going to challenge the authority that issued the NOTAM and who apparently thought a 400ft displaced threshold was no problem for the RNAV procedure , and is also not going to challenge the crew of a TK A330 who apparently agreed to perform that approach.

Somewhere down the line it would appear that very few people understand what " AR " really means, and I include myself in this.
But that said, I do not think one of the main cause of this accident was the displaced threshold.

ATC watcher:

No doubt about that. But, the crew was, or should have been, trained to understand it. Same for the aviation authority of Nepal. (although the approach was probably designed by experts outside of Nepal and, in fact, the aviation authority of Nepal may not have understood it, at least not as to the important nuances.)

Probably not. But, then again the illusions created by the airplane being in a vertical position in space at DA to land on a runway 400 feet closer could have been a contributing factor. hypothetical: "Reduce your descent, Captain, we are too low."