Serious incident to the Airbus A319 registered N703AV and operated by Avianca on 23/01/2020 en route [Investigation led by AIB / Costa Rica]

Preliminary data based on the notification from the authorities of Costa Rica:

While in the cruise phase at a flight level of FL 370, the pilot flying and the first officer the pilot monitoring, there are changes in the attitude, speed and vertical acceleration of the aircraft, causing a loss of 2500ft of altitude, over MMO speed low level announcement of hydraulic systems.