OEBs

Question 1

NO SRS ENGAGEMENT DURING GO AROUND BELOW MDA?

Answer 1

Occurs in FINAL APP managed guidance.
Reaching MDA - 50ft or MAP, FMGC disconnects AP/FD.
FD engages in current aircraft targets, because FMGC not in sync.
NO SRS GA TRK engagement!!

ACTIONS:
Disengage FINAL APP by pushing APPR p/b on FCU
or FD off.

Question 2

ERRONEOUS VERTICAL PROFILE DURING RNAV, LOC APPROACHES

Answer 2

FMGC builds vertical profile assuming altitude constraint at MAP is equal to rwy threshold elev + 50ft.
Therefore, if MAP is before RWY threshold, DON’T use FINAL APP mode. Approaches labelled as GPS on MCDU are not affected.

Question 3

ERRONEOUS ALTER FUEL PREDICTIONS UPON MODIFICATION OF A COMPANY ROUTE IN THE ALTERNATE FLIGHT PLAN

Answer 3

When crew modify CO RTE in ALTN F-PLN the FMS no longer stores ALTN fuel predictions. The FMS erroneously assumes there is no alternate F-PLN anymore for fuel predictions.

Enter manually a waypoint in the en-route F-PLN to start a new computation, then delete.

Question 4

NO ENGAGEMENT OF GUIDANCE MODE

Answer 4

RA transmits erroneous height indication.

During go-around, disconnect APs, set FD off then ON, Re-engage guidance mode as appropriate.
For subsequent approach, do not arm G/S mode.

Question 5

HYD ENG PUMP LO PR FOLLOWED BY HYD RSVR OVHT

Answer 5

Difference in pressure between G and Y are 500 PSI the PTU will automatically activate. Fluid leaks from G system, causing PTU to run which will then overheat the Y system. ECAM will ask to turn both pumps off - DUAL HYD FAILURE

PTU - OFF
PUMP - KEEP ON