Opération Tacaud was triggered by the capture of Faya-Largeau by the FROLINAT on 17 February 1978, opening the road to N'Djamena, capital of Chad.

France decided to send in troops to support the Chadian army, as had been previously done with Opération Bison a few years before.

The 3rd RIMa was sent in its entirety, along with The Navy offered one Breguet Atlantic plane for intelligence gathering, as well as naval commandos who were deployed at N'Djamena International Airport.

The Air Force offered eight SEPECAT Jaguar attack planes and a number of Transall aircraft for transport.

The 3rd company of the 3rd RIMa also joined in, from Mongo; as they approached Ati, the marsouins found themselves under heavy fire and had to call in air support, provided by the Jaguars.