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Not extending flaps while gear is extending

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Not extending flaps while gear is extending

Old 10th Feb 2019, 06:59
  #41 (permalink)  

Only half a speed-brake
 
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I like to think that in the Airbus world the need of correct GA sequence was understood well before the EK crash at DXB. If not, the old history remember/repeat rule will apply.

The FMA and lack of GA modes is the key point, not the L/G as such. In agreement with the above, if I close my eyes the flap lever is item 2 in the sequence; the gear lever movement would be 6 or thereabouts.

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Old 11th Feb 2019, 00:21
  #42 (permalink)  
 
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Originally Posted by vilas View Post
Cough
. Purely from go around perspective, we do and should separate gear and flaps. The flap is retracted from full to 3. Then FMA(which ensures TOGA&SRS) and sustained climb only then gear up. That's the lesson driven home by Dubai 777 accident. If the gear wasn't retracted it wouldn't have happened.
For years we were flap 3, positive rate, gear up. No FMA.... Yes we overcame these yesteryear moments and instilled FMA awareness, but I can't think of a G/A from the days of the inception of the A320 series whereby a hydraulic failure was caused by the simultaneous movement of both gear and flaps. And as noted above, we have a procedure whereby both are moved, in all our aircraft, daily, IAW SOP's with little issue. Makes for a great, quiet, efficient approach. As I said above, my thoughts are technical, not SOP related.
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Old 12th Feb 2019, 20:40
  #43 (permalink)  

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Even when the old ways were allowed to work , there was no simultaneous movement of flaps and L/G during the GA sequence. By the time pilot's hand touches the gear lever, the flaps would be well reconfigured.

Personally, I like the explanation already provided above, expanded. During approach, F2 take about 5 sec to extend against the airflow, powered by G & Y pressure delivered from one EDP in the OEI scenario. Simultanoues demand of the LG operation at that stage will cause hydraulic pressure drop below the ECAM warning level, causing nuisance warnings and god knows what other side effects in the F/CTL system. The demand is quite substantial, e.g. during normal take-off the PTU runs momentarily in support of the G HYD anyways.

To avoid the uncecessary, there used to be a note in the SOP so that the drill of extrending the flaps and gear could remain the same after an engine has given up. Exactly the way it shall be done, a good SOP set already caters for single failures.

Maybe the suggestion got removed in pursuit of operational benefits you speak of, whilst knowing no harm would be done - a simple change of heart?

Last edited by FlightDetent; 13th Feb 2019 at 05:30.
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