Hi Vilas
You are right (Kind of...) No where does it specifically specify you are to remain in the selected lever position during a Go around, although it does state if a circuit is planned then to leave it there. I'm pretty sure if Airbus had concerns they would make this in bold capitals but it tell us to clean up if a diversion is planned and I'm pretty confident having the lever in Flap 3 will keep us safe if we retract a stage of flap. In addition to a slat only approach our pitch attitude is already high compared to a normal Slat/Flap approach and pilots may have a tendency to raise the nose by the same amount as they normally would then if we factor in a stage of slat being removed if we were to make an approach in flap lever 2 then retracting a stage during a Go around...well you get my point.
But as mentioned above i did not state that Vls is dependent on lever but actual aircraft config. So in our case 2 stages of Slat only. If we were to retract a stage through force of habit from flap position 2 to 1 then we would change the actual config and would be in a possible sticky situation. If you get time Google 'Confirmation bias' it's very interesting what we as humans do in situations even when told what to expect.
Airbus is by no means perfect, and they know this! This procedure is a result of sensible thinking by the people who have designed this aircraft and seen the pitt falls through thousands of hours of simulated malfunctions and issues that have probably helped mould this procedure the way it is written today.
A good example of this is in the Green and Blue Dual Hyd failure were the procedure asks us to select manual thrust at around 200Kts...This is because the aircraft is in an aerodynamic mess (partial use of only half the elevator no aileron and 2 roll spoilers per wing to be used for banking) The designers were wise enough see that with the extension of the gear putting the aircraft into direct Law and flying at the approach speed (which again would be close to Vls and VSW) the aircraft MAY not cope well, hence the extension at 200kts and with manual thrust (they do not trust their own equipment in this particular circumstance) Could we leave the Auto thrust in...Yes. Would we crash...probably not. Is it wise...I would say no.
Could we fly and approach (G and Y Dual Failure) in flap lever 2...Yes but once again probably not wise.
Last edited by EGKK.; 15th Dec 2017 at 20:54.