PPRuNe Forums - View Single Post - Airbus trepidation... convince me otherwise!
Old 13th Jan 2012, 17:07
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rudderrudderrat
 
Join Date: Oct 2009
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Hi OK465,

Sorry the only information I have is from my current FCOM. (My bolding)
What's your latest source?

FCOM OEB 201/2 says:
!Erroneous Radio Altimeter (RA) height indication
APPLICABLE TO:
All A318/A319/A320/A321 operators
... other pages of faults and explanations ....

Warnings / Callouts
-
Untimely Terrain Awareness and Warning System (TAWS) alerts
-
Untimely or absence of “RETARD” callout
-
Untimely L/G GEAR NOT DOWN ECAM warning
-
Absence or interruption of RA automatic callout (height announcement)
-
Activation of AUTOLAND warning light in ILS (or MLS, GLS) approach (Refer to FCOM 1.22.30) with AP engaged in LAND or FLARE mode when:
o
One RA height goes below 200 feet and
o
The difference between both RA height indications is greater than 15 feet
Note: There is no ECAM message or audio warning in association to the AUTOLAND warning light. The AUTOLAND warning can be triggered even if AUTOLAND is not planned
Auto Flight System mode changes (indicated on FMA)
-
NAV mode engagement not possible after take off
-
During an ILS (or MLS, GLS) approach, and depending on the engaged Flight Guidance (FG) modes, the consequences may be:
o
Untimely/early engagement of the LAND / FLARE / THR IDLE modes if the RA height used by the FG is erroneous and lower than the real height.

Note: During ILS (or MLS, GLS) approach with AP and A/THR engaged, THR IDLE (RETARD) mode untimely engagement will be associated with an initial pitch attitude increase due to FLARE mode engagement.
o
In AUTOLAND, the LAND / FLARE / THR IDLE modes will not engage, if the RA height used by the FG is erroneous and higher than the real height.
o
In case of Go-Around and if the RA is still frozen at a very low height indication:

SRS and GA TRK modes engage

NAV, HDG or TRK lateral modes cannot be selected

LVR CLB will not be displayed on the FMA at THR RED ALT

ALT* and ALT will not engage at FCU altitude
Disconnecting AP and resetting both FDs enable to recover basic modes (HDG and V/S).
During an ILS (or MLS, GLS) approach with AP engaged, if an erroneous and very low RA height indication occurs, THR IDLE and FLARE modes may engage early with the following consequences:
-
In CONF FULL, the High Angle of Attack protection is not available. As a consequence the autopilot will not automatically disconnect at α prot +1°. If the flight crew does not immediately react, the angle-of-attack will increase and may reach the stall value.
-
In configurations other than CONF FULL, the High Angle of Attack autopilot disconnection is available. The autopilot will automatically disconnect at α prot +1°.
-
Loss of ALPHA FLOOR.
-
The LOW ENERGY AUDIO WARNING – “SPEED SPEED SPEED” - remains available. In case of activation of LOW ENERGY AUDIO WARNING, the flight crew must react as per procedure (QRH 2.03).
-
In CONF FULL, the auto-trim function is inhibited.
-
In manual flight or after AP disconnection, significant longitudinal sidestick input may be required."

If only No1 AP is engaged with No 1 RAD ALT giving erroneous readings of below 30 feet, then the above may occur.
With no Alpha Floor - that sounds like Habesheim to me.

How the heck could anybody just sit there and watch it?
rudderrudderrat is offline