Jetstar A320 enroute on Mar 12th 2014, alpha floor activation

A Jetstar Airways Airbus A320-200, registration VH-VQY performing positioning flight JQ-7991 from Melbourne,VI to Darwin,NT (Australia) with 2 crew, had just cleared from FL360 to FL380 and had just reached FL380 abeam Mildura,VI (Australia) when the crew noticed the airspeed was increasing. The crew reduced thrust to idle, extended the speedbrakes and disengaged the autopilot in order to reduce the airspeed, which resulted in speed warnings and a brief activation of flight envelope protection function. The aircraft continued to Darwin for a safe landing without further incident.

Australia's TSB reported an investigation has been opened into the flight envelope protection event (later adding more detail about the sequence of events).

On Mar 18th 2014 the French BEA reported in their weekly bulletin that the aircraft was climbing from FL360 to FL380, after the climb was completed the airspeed increased and the crew disconnected the autopilot in order to control the speed. The speed then decayed resulting in Alpha Floor Activation. Australia's TSB is investigating the occurrence rated an incident.