INQUIRY DAVID KAMIIMSKI-MORROW LONDON
Missed airspeed risk led to stall-protection activation
Air France A320 was left with "low energy reserve" during its final approach to Marseille.
Pilots of an Air France Airbus A320 allowed the jet's airspeed to bleed away while turning for its final approach to Marseille, resulting in thèe activation of its stall-protection System.
French investigation authority BEA says thè A320 (F-HBNE) was operating with a
"low energy reserve", given the aircraft's altitude and configuration.
It had been conducting a shortened left-hand approach to run-way 31L.
The crew had selected full-flap configuration during the downwind leg leaving the aircraft's autothrust pursuing a target approach speed of 136kt (252km/h).
BEA says this reduced the margins available to avoid a stall during thè subsequent turns to base and final, but that this risk was not identified by the crew.
The first officer, who was flying, began the turn to final about 2.4nm (4.8km) from the runway threshold.
He briefly gave nose-down commands, increasing the descent rate to 1900ft/min, and the jet entered a 26° left bank - and a crosswind from the left at an altitude of 900ft.
The first officer, noticing that the jet was low on approach, then commanded nose-up for 6s.
While this increased the pitch and reduced the descent rate to 500ft/min, it also led the airspeed to fall away from 143kt to 132kt. The airspeed stayed below the 136kt approach target figure for 6s.
BEA says that the aircraft's angle-of-attack reached 12° and a speed warning sounded. The A320 descended to a minimum height of 474ft above ground before, as a result of the stall-protection System engaging, and the crew's executing a go-around, it began to climb away.
Investigators believe the situation was exacerbated by the absence of deviation call-outs from the monitoring pilot who, it says, remained "confident" in the first officer's ability to conduct the manoeuvre.
None of the 174 occupante was injured during the incident, which followed a flight from Paris on 11 March 2013.
BEA points out that the incident bore a number of similarities to an Aprii 2012 event involving an Air France A320 on approach to Tel Aviv.
L’incident report:
Incident: Air France A320 at Marseille on Mar 11th 2013, approach to stall during visual approach
E un altro simile:
Report: Air France A320 at Tel Aviv on Apr 3rd 2012, approach to stall on turning final results in Alpha Floor and flaps overspeed
E' evidente che la complacency in questo caso ha svolto un ruolo di primo piano, ma voglio rivolgere la seguente domanda agli esperti di 320:
"C'è un qualche caso in cui le SOP prevedano l'estensione del flap d'atterraggio in sottovento???"
Safe flights
Romano c'è