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RNAV approach intermediate segment


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RNAV approach intermediate segment

Old 20th October 2019 | 13:55
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From: Amantido
RNAV approach intermediate segment

It is well clear that it is mandatory to be established on final approach track at least 2nm before the FAF, but can someone redirect me to the IR-OPS regulations that mandate this 2nm segment be also in level flight rather than continuous descent from TOD?
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Old 20th October 2019 | 14:20
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From: IRS NAV ONLY
There is no EASA regulation requiring this, simple as that.
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Old 20th October 2019 | 14:39
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From: Amantido
As I thought, on our Jeppesen charts we have the procedure altitude with MANDATORY written underneath the level segment and that confused me.
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Old 20th October 2019 | 15:31
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From: IRS NAV ONLY
Well, that could be airport/procedure specific thing then. But in general, you are not required to reach FAF in level flight on an RNP approach.
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Old 20th October 2019 | 17:26
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From: BLQ
I believe this is a subject that concerns the Operator and the Manufacturer rather than the Authority.
Airbus, for example, recommends being leveled before the final descent point to meet the engagement criteria for the final descent.
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Old 20th October 2019 | 18:20
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From: Wanderlust
Originally Posted by EI-PAUL
I believe this is a subject that concerns the Operator and the Manufacturer rather than the Authority.
Airbus, for example, recommends being leveled before the final descent point to meet the engagement criteria for the final descent.
If you are higher than final descent altitude the final descent arrow will not be in blue colour. And FINAL APP will not engage.
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Old 20th October 2019 | 18:56
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Originally Posted by vilas
If you are higher than final descent altitude the final descent arrow will not be in blue colour. And FINAL APP will not engage.
In cruise in a A320, at F370 got direct to the FAF for a straight in visual backed up by the RNAV, and cleared descend all the way down. Had FINAL APP all the way from TOD till FD off at MDA.....
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Old 20th October 2019 | 19:11
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From: BLQ
Originally Posted by vilas
If you are higher than final descent altitude the final descent arrow will not be in blue colour. And FINAL APP will not engage.
If you are higher than final descent point the final descent arrow may not turn blue. And final approach may not engage if final approach criteria are not met IAW FCOM DSC-22_30-80-30-20.
This statement is not necessarily true if we're higher than the final descent altitude.
This in the reason why airbus recommends to arm FINAL APP mode when the TO waypoint is the final descent point. Ref: FCTM PR NP SOP 120 GUI Approach using final approach guidance.
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Old 20th October 2019 | 20:09
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The "mandatory" note for the altitude on the Jepp refers to the crossing of the fix, not the flying of the segment before it. It's equivalent to how in some SID/STAR presentations there's a under- and -overline at the number (as opposed to just an underline for "at or above," etc.)
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Old 21st October 2019 | 09:10
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From: Commuting not home
The word "MANDATORY" on Jepp charts is their unique graphic presentation that the underlying procedure as defined in the National AIP has a "hard" - "exactly at" altitude restriction.

As correctly pointed out above, or maybe not, a continuous descent without a level segment does not automatically mean you screwed up, arrived at FAF above the coded altitude and failed to meet the activation criteria for the VNAV guidance to final approach.

My understanding is the OP flies the 737, so perhaps holding the airbus horses would be prudent. The lingo and modes there is many times confusing even for the rated guys, plus the "B" manufacturer's kit is superior in this regard.

Last edited by FlightDetent; 24th October 2019 at 12:50.
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Old 22nd October 2019 | 18:32
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From: Wanderlust
In cruise in a A320, at F370 got direct to the FAF for a straight in visual backed up by the RNAV, and cleared descend all the way down. Had FINAL APP all the way from TOD till FD off at MDA.....
According to Airbus FINAL APP is designed to fly the vertical profile from final descent point. If FINAL APP is engaged too early and there are level off segments they will not be respected. DES is the appropriate mode to fly.
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Old 22nd October 2019 | 20:31
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Originally Posted by vilas
According to Airbus FINAL APP is designed to fly the vertical profile from final descent point. If FINAL APP is engaged too early and there are level off segments they will not be respected. DES is the appropriate mode to fly.
Well, in our case TOD was the final descent point....
I'm sure you are right about the correct mode, I was just curious what it would do, we were visual all the way in, and no level flight was planned.
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