Originally Posted by
CVividasku
As long as there isn't anything preventing you from flying Vapp, I don't see why you would be forced to used managed speed.
My mind has now moved on to something else. The use of reversers (thrust lever management) in case of inoperative reversers (all inop)
The FCTM is very very unclear about this. I will let whoever wants to read it and be surprised (or not)
Q1. SOP
INITIAL APPROACH:
(…) MANAGED SPEED....................................................... ......................CHECK ▏ PF
If ATC requires a particular speed, use selected speed. When the ATC speed constraint no longer applies, return to managed speed.
Q2.
AT LEAST ONE REVERSER OPERATIVE
If at least one reverser is operative, the general recommendation is to select the reverser thrust on both engines during rejected takeoff (RTO) and at landing,
as per normal procedures.
NO REVERSERS OPERATIVE
If no reversers are operative, the general recommendation is to not select the reverser thrust during RTO and at landing.
However, the PF still sets both thrust levers to the IDLE detent, as per normal procedures.
TAM 3054 accident.
After this accident the procedure changed and so did the wording as highlighted above.
From the report:
The FDR transcript shows that immediately after the warning, the flight computer recorded the left thrust lever being retarded to the rear-most position, activating the thrust reverser on the left engine, while the right thrust lever (controlling the engine with the disabled thrust reverser) remained in the CL position.
So all Airbus is trying to tell you is: do not forget to close the thrust levers when you land. It may sound obvious to 99.9% of the pilots but as there was an accident involved, lawyers got in the way.
With both reverser inoperative if you do select IDLE REVERSE the FADEC will command an increased N1 which will adversely affect your landing distance as there will be no reverse deployment.
With 1 REV INOP, same will happen on the Inoperative reverser but the operative one will compensate and the loss in performance is negligible. That’s why you can handle your reverse as you would normally do with no failures/MEL.
p.s. Do not confuse IDLE DETENT with IDLE REVERSE.