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767-300ER
8th Oct 2015, 14:35
Can other pilots speak to their company's narrow body Airbus procedures?


On a VOR approach why does one have to display the VOR rose, when there is a VOR needle on the ND? The needle is good enough for an NDB approach?


Are you allowed to adjust the FPA from the published FPA for a non-precision approach? e.g. some aircraft types in our fleet are allowed to adjust their FPA +/- within certain limits (-3.5 as a max), our Airbus SOPs don't allow us to do this.


Are you allowed to start your FPA descent 0.3NM prior to the FAF? Are other aircraft at your company allowed to do this? I can't understand why Airbus gets a "let" on this.


Are you allowed to have your tray tables open for t/o and landing? or is this my company's rigid thinking, I don't think this is an AFM limitation.

Metro man
8th Oct 2015, 17:38
PF has VOR rose, PM has ND to monitor.

FPA may need to be adjusted to meet check heights, it may not be 100% accurate so why bust an altitude or end up high and unstabalised ?

We fly CANPA and 0.3nm is to allow for the distance it takes the aircraft to react and actually start descending. Works well, also we add 50' to the MDA so as not to go below.

Tables away for us as well.

FlightDetent
10th Oct 2015, 02:26
On a VOR approach why does one have to display the VOR rose, when there is a VOR needle on the ND? The needle is good enough for an NDB approach There is no such Airbus FCOM requirement. I had a TRE once comment on this, that with ROSE selected I removed some available information and reduced situational awareness. Fair enough.

Are you allowed to adjust the FPA from the published FPA for a non-precision approach? e.g. some aircraft types in our fleet are allowed to adjust their FPA +/- within certain limits (-3.5 as a max), our Airbus SOPs don't allow us to do this. Either it is your Co. SOP's, or Airbus OEM FCOM :E Easiest indeed if they are the same. We can and must adjust FPA as to fly the correct vertical profile. What exactly do you mean by not allowing to adjust FPA, as if not touching the FCU knob after pull?

Are you allowed to start your FPA descent 0.3NM prior to the FAF? Are other aircraft at your company allowed to do this? I can't understand why Airbus gets a "let" on this. We pull FPA at -0.3 NM in order to descend at FAF. This is type specific handling of the autoflight system. Whether or not other aircraft have the same I od not know, but why not.

Are you allowed to have your tray tables open for t/o and landing? or is this my company's rigid thinking, I don't think this is an AFM limitation.I actually researched that one some time ago and found the same, no AFM limitation. However the company procedure was "table must be stowed for takeoff and landing" and local CAA viewpoint was the same. Note too, that MMEL allows INOP in stowed position only.

take care, FD.

767-300ER
11th Oct 2015, 18:47
Thanks for your replies...

What I meant by adjusting FPA is that if the chart says -3.0 FPA, then that's what we must set...if you are late setting the FPA, you are stuck with -3.0

Other fleet types can adjust the -3.0 FPA up to a maximum of -3.5 FPA to account for a late setting of the FPA etc..

I can't see why you couldn't adjust the FPA, since you descend to MDA and no lower, it's not like you violate any IFR altitude(s).

Anyone care to comment on whether their company SOPs have them adjust the non-precision approach FPA to account for cold weather? We have a table to make an adjustment...

IMO, it just complicates an already busy procedure and you gain very little in making this adjustment. It's a non-precision approach , for goodness sake, and we treat it like a CATIII approach it trying to make it so precise....

Measure with a micometer and cut with an axe!

Field In Sight
11th Oct 2015, 19:07
I did a sim with the CAA ops inspector on board and for thought I should only start the decent at the FAF. As in my IR rating test.

I got picked up for it as I ended up initially high as the FCOM said start down 0.3d before TOD.

RAT 5
11th Oct 2015, 19:25
I did a sim with the CAA ops inspector on board and for thought I should only start the decent at the FAF. As in my IR rating test.
I got picked up for it as I ended up initially high as the FCOM said start down 0.3d before TOD.

IMHO this is not type specific. As you said: an IR item. That is not type specific. Most airlines I flew for, using V/S, started down at -0.3nm. I then 'graduated' to a VNAV/LNAV airline. Guess what, the a/c starts to reduce thrust and gently nose over just before the FAF. Perfect. Guess what: the same XAA said that on a V/S approach you could NOT select the descent before the FAF. Consequent is you have to select a higher than normal ROD and then assess when you are on the path to reduce ROD to maintain the path. Talk about making a difficult job even more so. It increases the workload of both PF & PM close to the runway. WHY?
In this case it is not type specific it is XAA specific. Why should you operate the a/c in a different way manually than when the automatics control it? Simple!

Gary Lager
11th Oct 2015, 20:10
Surely the requirement is that you don't descend before the FAF; if you allow for inertia of the aircraft selecting the target V/S or FPA at about -0.2nm should still not cause a descent below the platform altitude until the required point.

IR stuff sort of gets woolly around CDFAs as technically we should ensure that all platform altitudes are crossed at -0ft, but if this would destabilise the otherwise sensible CDFA then it can be less safe, thus examiner guidance is to exercise judgement.

Use of ROSE/ARC modes on ND during VOR approach: only caveat is that to use ARC mode NAV ACCY must be HIGH. If it isn't, switch to VOR ROSE mode (which is a far easier display to use if you are manually adjusting/monitoring tracking). If NAV ACCY is LOW then ARC has little useful info on it besides the needles as planned track and EGPWS info is compromised.

Not being allowed to adjust the selected FPA if you have deviated from the planned vertical profile makes no sense to me. Would you be allowed to adjust your V/S manually if you decided to disengage all AP/FD and fly the approach in raw data? Has the person who wrote this rule ever flown a CDFA non-precision approach at all, let alone in an airbus?

FlightDetent
11th Oct 2015, 22:37
Anyone care to comment on whether their company SOPs have them adjust the non-precision approach FPA to account for cold weather? We have a table to make an adjustment...

There is a very nasty trick with FPA about cold temp on Airbus. The FPA is not geometric, and unfortunately gets affected by cold temp. I do not believe it is anywhere in FCOM. Thus, if you correct the FAF altitude, you need to increase FPA.

FD.

Gryphon
12th Oct 2015, 20:27
Are you allowed to adjust the FPA from the published FPA for a non-precision approach? e.g. some aircraft types in our fleet are allowed to adjust their FPA +/- within certain limits (-3.5 as a max), our Airbus SOPs don't allow us to do this.
Are you allowed to start your FPA descent 0.3NM prior to the FAF? Are other aircraft at your company allowed to do this? I can't understand why Airbus gets a "let" on this.

FCOM PRO NOR SOP 18-C. Approach using FPA guidance.

TRK FPA pb (Bird)...................................................... ...................SELECT
FPA FOR FINAL APPROACH.................................................... ...............SET
At 0.3 nm from the Final Descent Point: FPA .................................PULL
FPA MODE........................................................ ..............CHECK ENGAGED
‐ Check NAV FPA, TRK FPA or LOC FPA is engaged.
POSITION/FLIGHT PATH ................................MONITOR/ADJUST
GO AROUND ALTITUDE.................................................... ......................SET

FCTM NO-130 NPA, FINAL APP-SELECTED.
For a selected approach, the Final Path Angle (FPA) should be preset on the FCU 1 NM prior to the the point where the final descent starts at the latest. A smooth interception of the final approach path can be achieved by pulling the FPA selector 0.3 NM prior to the point where the final descent starts

Anyone care to comment on whether their company SOPs have them adjust the non-precision approach FPA to account for cold weather? We have a table to make an adjustment...


FCTM NO-130 Cold weather operations.-
For all Non Precision Approaches, there is a minimum OAT. Below this temperature, the error on the barometric altitude is no longer acceptable, and altitude should be corrected in temperature. As it is not authorized to make these altitude corrections to the final approach segment of the FM Flight Plan (F-PLN) through the MCDU, it is not possible to use FINAL APP when OAT is below this minimum OAT. The flight crew must then use selected vertical guidance. This minimum OAT is indicated on the approach chart or must be defined by the operator based on the terrain profile (plus adequate margin). For more information on approach in cold weather, Refer to FCTM SI-010 Cold Weather Operations and Icing Conditions

Are you allowed to have your tray tables open for t/o and landing? or is this my company's rigid thinking, I don'

In the FCOM PRO NOR SOP you can read before take off and landing phases, Sliding table.....stow.

Jonty
14th Oct 2015, 09:12
1) For the approach you should have raw data for the approach type displayed. In our company it depends on the TRE as to weather the needles in ARC mode is sufficient. I use the ARC mode and needles, and take the de-brief if necessary.

Interestingly, if your company audits the approach and charts in a particular way, you don't even need the nav aid to comence the approach. So you could do a VOR approach with the VOR unserviceable. Which makes sense, as in a GPS aircraft it doesn't actually use the VOR to fly the approach. LIM 22 - 10 - Use of NAV mode for approach

2) are you saying your not allowed to correct the set FPA during the decent? If so, that's crazy!

3) this is the same as other aircraft. In the B757, before managed approaches, we used to start the decent .5 of a mile before the decent point.

4) this ones Airbus I'm afraid. Apparently the aircraft was not certified with the tables out. So they have to be stowed.

Superpilot
14th Oct 2015, 16:28
Lord knows how we flew VOR/NDB approaches prior to the advent of the FPA selection knob :rolleyes:

RAT 5
14th Oct 2015, 17:33
For a non-AB pilot: what design changes were made to the selector after the Strasburg NPA crash some years ago? They selected V/S 3300 instead of 3.3 FPA.

FlightDetent
14th Oct 2015, 18:18
I was told it were the digits in FCU, v/s -33 to v/s -3300 (as opposed to fpa -3,3) most probably same at the FMA. This needs to be confirmed however.

regards,
FD.

767-300ER
19th Oct 2015, 16:33
Jonty

we can't modify the published/calculated FPA...if one mis-sets the FPA you could set the correct FPA, but if you were late setting the FPA at the FAF then you can't modify it...ie published FPA is -3.1 but you were late setting it, and want to set -3.3....

we can't do that....

compressor stall
19th Oct 2015, 17:17
And the rationale behind that is...??? Airbus says...


POSITION/FLIGHT PATH........................MONITOR/ADJUST

767-300ER
20th Oct 2015, 15:16
The rationale?

Who knows, and why are trying to seek a logical answer, I suspect that logic doesn't enter into this....

AKAAB
21st Oct 2015, 20:29
Regarding Cockpit Tray Tables - I've been involved with the FOEB MMEL process for over ten years and have asked Airbus this question numerous times seeking justification for the MMEL requiring the tray to be stowed or removed.

The most informative response I've ever gotten was that they believe it was stowed during flight evaluation tests and no determination has been made as to whether it was okay to have it extended for takeoff or landing. Essentially - "we don't care"

The FAA has stuck with the most restrictive MMEL option in the absence of any supporting data from Airbus. There is no other regulatory requirement in the FARs or other regulatory documents.

Don't get me started on speedbrake use to meet emergency descent parameters.