TobiBS wrote:
Completely agree on that, but in my understanding the main purpose of CDFA is to prevent the pitch/power changes, especially the last one at MDA, because the first (establishing level flight) can easily lead to a stall, while the second (establishing final descent) can lead to an unstable approach, because the MAPt does not assure 3deg GPA.
Well yes, the latter re stable approaches is the counter argument. Stalling is not done “easily” in a dive and drive and requires pilots to make mistakes.
JasonC wrote:
Stalling is not done “easily” in a dive and drive and requires pilots to make mistakes.
If pilots wouldn’t make mistakes, we could change a lot of the rules and procedures. My point here is: The simpler a procedure and the less skills or other requirements it takes, the less error prone it generally is. Of course easily was too much in this case, but the distraction of trying to look out for the runway can at least result in scratching the MDA, which is the other possible unsafe outcome.
But all overall what_nextis right, the case here was a precision approach, so everything we doscuss does not apply.
TobiBS wrote:
If pilots wouldn’t make mistakes, we could change a lot of the rules and procedures. My point here is: The simpler a procedure and the less skills or other requirements it takes, the less error prone it generally is.
I really don’t understand your point. But D&D is clearly an easier procedure. CDFA is probably better in most cases but takes more skill.
JasonC wrote:
I really don’t understand your point. But D&D is clearly an easier procedure. CDFA is probably better in most cases but takes more skill.
Well that seems to be the issue here. For me in contrast CDFA is superior in simplicity. The reason is, that there is a GPA charted which allows to pass all intermediate altitudes and reach the visual descend point ideally without any adjustment. Then if you hit the DA, you are deciding between continuation and go-around.
If you are flying D&D contrary, there can be segments of different length to intermediate altitudes, which are passed only, if you carefully think about it before (hence creating a CDFA), or you are stopping the descend and flying level from time to time. This change between descend and level flying in my oppinion needs more skill then to start a continous descend.
What is your argument, that a CDFA takes more skill?
TobiBS wrote:
What is your argument, that a CDFA takes more skill?
It is my opinion based on my experience of both.
I have not been following along, but is EU-OPS not valid anymore?
According to EU-OPS, the aircraft must not descend below MDA on a NPA. This is in Subpart E of OPS 1 (1.430 (b) 1 (i)).
Also, NPAs must be flown according to CDFA (OPS 1.430 (d) 2).
Therefore, some pilots use a DDA (derived DA) where the 50 of 100 ft. is added to the DA, which point is then treated as the DDA point or Go-Around point.
JasonC wrote:
But D&D is clearly an easier procedure. CDFA is probably better in most cases but takes more skill.
I disagree! I find CDFA much easier to fly.
When I first got my IR in 1987, D&D was the only way. The CDFA concept didn’t even exist.
When I renewed my IR in 2014 after my 1995-2012 break in flying, I was amazed how much easier a CDFA was.
AeroPlus wrote:
EU-OPS not valid anymore?
Yes, but you seem to refer to JAR-OPS which have not been in force for many years. The ops regs in force now are part-CAT, part-NCO etc.
TobiBS wrote:
TLA: Three Letter Acronym
Two-letter acronym as well 
DA Decision Altitude (AMSL)
DH Decision Height (above threshold)
AeroPlus wrote:
According to EU-OPS, …
EU-OPS and JAR-OPS applied only to commercial operations.
