Two cases of inappropriate V/S target during an autoflight reversion to V/S mode after a go-around were recently reported to Airbus. In both cases, the inappropriate V/S target resulted in a pitch down command of the autopilot with high thrust. The flight guidance used the previously selected V/S value set during the preceding ILS glide slope intercept from above as a V/S target for the mode reversion.This article describes one of these events in detail and explains the conditions that caused this autoflight behavior. It provides operational recommendations to flight crews to prevent and detect this situation. It also lists the system enhancements that were launched to avoid the use of an inappropriate V/S or FPA target during a mode reversion of the flight guidance.
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