Method and control unit for controlling the play of a high-pressure turbine

A method for controlling the clearance between the blade tips of a high-pressure turbine of a gas turbine aircraft engine and a turbine shroud, including the controlling of a valve delivering a stream of air to the turbine shroud, this method further including the following steps: the detection of a transient acceleration phase of the engine; the receiving of an item of data representative of the gas temperature at the outlet of the combustion chamber of the engine; a valve opening command, to deliver the air stream to the turbine shroud or to increase the flow rate of the delivered air stream, if the transient acceleration phase is detected and if the gas temperature at the outlet of the combustion chamber is greater than a first temperature threshold corresponding to a degraded clearance characteristic of an aged engine, this threshold being less than an operating limit temperature of the engine.