Definition

A Multifunction Control and Display Unit (MCDU), sometimes called a Multipurpose Control and Display Unit, is a device that serves as the heart of an aircraft's Flight Management System (FMS). The MCDU includes a keypad and a liquid-crystal display that allows a pilot to enter and modify flight plans. The MCDU also serves as the control head for the radios; presents flight information such as fuel consumption, time elapsed, and time to go; and allows input of engine thrust ratings and other data. MCDU functions also include communications via the Aircraft Communications, Addressing, and Reporting System (ACARS).