The invention relates to a method for synchronising the engines of an airplane, according to an activation logic having a deactivated state, an armed state and an activated state, in which: the switching of the activation logic from the armed state to the activated state is carried out via a first and then a second successive intermediate state; every instance of the activation logic switching from the intermediate state to the activated state involves the following: taking into consideration, on each engine, the activation state of the synchronisation, and exchanging said data between the engines; the switching of the activation logic of one of the engines to the activated state requires that the safety and activation conditions of the other engines are all met; if one of the engines enters the deactivated state, the others do so as well; and, for each engine, the switching of the activation logic from the armed state to the first and then to the second intermediate state takes place automatically when a first portion and then a second portion of the safety and/or activation conditions are met.