A320 Mode Reversions

Today we take a look at A320 mode reversions. What are reversions you may ask? Reversions are automatic mode changes that take place when unexpected or unreasonable demands are asked of the aircraft ensuring consistent, coherent AP, FD and ATHR operations. We will take a look at them in the following order: 00:20 Reversion due to a change of the FCU selected altitude. 02:25 Reversion due to the loss of NAV mode (Manual or Automatic). 02:50 Speed protection when FD orders are not followed by the flight crew (AP not engaged). 03:40 Speed protection due to excessive V/S. Acronyms used in this video: AP – Autopilot, ATHR - Auto thrust, FD – Flight Director, V/S – Vertical Speed, SID – Standard Instrument Departure, STAR – Standard Arrival Route, VMAX - Maximum Allowable Speed, VLS - Lowest Selectable Speed Trivia: - When a mode reversion occurs, it is accompanied by a triple click aural warning. - Airbus defines mode reversions as ’mode changes that unexpectedl