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GLuis103
24th Mar 2014, 13:44
Hello all, can anyone make this clear for me, it is a doubt that appeared today while checking some charts. I was looking at an ILS chart for LPFR (Faro, Portugal) and on the ILS Loc Out minimums with says DA, does that mean I not able to level off and continue to the MAP, which in this case is at 0.6DME ? Or should I see it as an MDA instead of DA ?

P.S. This is a recent chart, updated on the 21st of February on the present year

A4
24th Mar 2014, 14:57
What type of aircraft? If you're talking about a jet then "dive'n'drive" doesn't apply, the approach is flown as a CDFA (Continuous Descent Final Approach) like a pseudo ILS. The DA is treated in exactly the same way as an ILS DA i.e. at DA if not visual you go-around.

GLuis103
24th Mar 2014, 15:08
I´m sorry, I forgot to mention the type of aircraft, in this case I´m considering Category A or B aircraft. So I guess Non-CDFA is applicable, am I correct ?

bucks_raj
24th Mar 2014, 16:37
ILS LOC Out approach... Seriously!:=

GLuis103
24th Mar 2014, 16:54
wow once again, i´m sorry, I meant GS out, not LOC. That wouldn´t be very nice lol

flybmi
24th Mar 2014, 17:51
GLuis103,

Are you flying for an operator or doing your IR training?

In order for the reason that 'DA' has published on what is a non-precision to become clear you need to do some reading on CDFAs (Continuous Descent Final Approaches). Your school or operator should be able to provide you with some reading material. A CDFA allows you to fly a continuous descent from the FAF to the DA(MDA) and avoids inefficient level segments in the approach and a level off from the MDA to the MAP.

Just as a quick internet find, have a read of the following: Continuous Descent Final Approach (http://code7700.com/cdfa.html)

If you are practicing the old 'dive and drive' (i.e. leveling off at the platofrm altitudes and then the MDA to the MAP) then you will fly to an MDA as you described and fly level in the different segments along the approach.

If you're flying a CDFA then you continue to the MDA(DA) + an appropriate additive if applicable and treat it like a DA on a precision approach. But remember it is still an MDA so you cannot descent below it, hence the additive to take into account height loss during a missed approach in most types. Note that during a CDFA platform altitudes become SMAs (segment minimum altitudes) and your descent path should be calculated to cross at or above them.

GLuis103
24th Mar 2014, 19:12
First of all thank you for taking the time to answer this.

I´m currently on my IR training, that´s why this question came across. But, to make things clear in my head after spending some time today reading Doc. 8168, making a CDFA automatically means that we´ll be using a DA, correct ? Otherwise, if we leveled off at the MDA and continue until MAP it would no longer be a CDFA.

The thing is, on the chart it make no reference to MDA or CDFA, so, with GS Out , making it a non-precision app, does that mean once I reach my GS Out DA without rwy in sight I would have to automatically G/A ?

GLuis103
24th Mar 2014, 19:26
flybmi, the link you gave me pretty much made everything clear, I had two or three wrong ideas about CDFA and Non-CDFA, I should have read it before answering straight away ! Thanks once again !