PDA

View Full Version : A320 normal ops queries


EIU_EEC
28th Jan 2013, 12:09
Hi 320 pilots. A small confirmation. The green yaw command bar(yaw bar) on pfd during take off and rollout phase, guides the acrft along rwy centreline. Supposing we have ils for rwy 27 but 09 doesnt have ils, and we use 09 for take off.Normally if 27 was dep rwy, fmgs would have autotuned ils 27 and usual indications by yaw bar.
But if we manually input that for a 09 takeoff, will the yaw bar appear with RWY on FMA??and if it does,will there be reverse sensing??

2. Next query is about tropopause entry in init a. The fcom pro sup 22-20 states
To minimize the effect of temperature model error in the FMS computation of the Recommended Maximum Altitude (REC MAX ALT), the ECON CRZ Mach Number, and the ETA parameters: During the flight plan initialization or during flight, DO NOT MODIFY the default troppause value (36 090 ft) displayed on the INIT page or the FUEL PRED page of the MCDU
Thus if we have a tropopause of 45000 say...would you or would you modify the default?? Would you go by this proc?

EIU_EEC
29th Jan 2013, 04:29
any answers??

rudderrudderrat
29th Jan 2013, 09:36
Hi EIU_EEC,
But if we manually input that for a 09 takeoff, will the yaw bar appear with RWY on FMA??and if it does,will there be reverse sensing??
Yes and Yes.
It is better to cheat and simply look out of the window for the runway center line.

Thus if we have a tropopause of 45000 say...would you or would you modify the default??
Yes
Our SOP is to "check and modify the CRZ FL TEMP and tropopause level according to the OFP" (computer flight plan).

I-2021
29th Jan 2013, 10:24
Hi EIU,

Q1 :

I have never tried to hard tune an ILS frequency for the opposite runway on takeoff as I do not really see the point of doing so.

Anyway from the FCOM

The RWY engagement conditions are:
‐ The conditions required for SRS mode engagement:
• V2 is inserted in the MCDU PERF TAKEOFF page
• Slats are extended
• The aircraft has been on ground for at least 30 s.
‐ The aircraft is receiving a LOC signal and LOC deviation is less than 1/2 dot
‐ The aircraft heading is within 20 ° of the ILS related course
‐ The ILS course is identical to the runway heading of the origin airport as selected for the active
flight plan, if any.

According to the last 2 conditions you will not get any indications, even if you try.


Q2 :

The procedure is applicable to the FMGS II Thales, therefore other FMGS versions are not concerned

During the flight plan initialization or during flight, DO NOT MODIFY the default troppause value
(36 090 ft) displayed on the INIT page or the FUEL PRED page of the MCDU
ENTER the temperature on the CRZ WIND pages at the expected CRZ FL

That's how we do it for the affected versions.

Cheers !

Checkboard
29th Jan 2013, 10:32
The green yaw command bar(yaw bar) on pfd during take off and rollout phase, guides the acrft along rwy centreline.
:confused: I think you'll find that the pilot guides the aircraft along the runway centre line during take off. :hmm:

Gryphon
29th Jan 2013, 11:30
FCOM. PRO-NOR-SRP-01-30 MONITORING THE TAKEOFF

Note: ‐ RWY mode appears if an ILS is tuned to a station corresponding to the departure runway. Otherwise no lateral mode comes up until the aircraft has lifted off.

PRO-NOR-SRP-01-30 TAKEOFF USING THE LOCALIZER OF THE OPPOSITE RUNWAY

 If the localizer, of the ILS associated with the opposite runway, must be used for takeoff:
SELECT the RAD NAV PAGE.
ENTER the ILS IDENT.
If the ILS is in the database, the system tunes the proper frequency.
Check that the ILS front course is displayed in the CRS field.
Note: This may trigger the “RWY/ILS MISMATCH” message. Disregard it.
 If the ILS is not in the database:
SET the appropriate frequency, and SET the ILS front course in the CRS field

DESELECT the LS pb on the FCU.
Since the PFD displays reverse deviation.
DESELECT the LS pb on ISIS.
Since ISIS displays LOC reverse deviation.
SELECT ROSE-ILS on one ND.