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This paper addresses the experimental study of hot jets impingement on a concave wall. Both low and high Mach number conditions have been investigated. Infrared thermography is used to measure the wall temperature evolution during the heating. This temperature mapping provides the boundary condition necessary to solve the transient heat equation in the wall. From this, heat transfer and Nusselt number are derived and their behaviour compared to literature on the subject when possible. Finally, a correlation of Nusselt versus Reynolds, Prandtl and the nozzle to wall distance is proposed. In order to prevent the airplane performances reduction caused by ice particles entering the engine during the flight, some small anti-icing impinging jets of hot air taken from the combustion chamber are commonly designed. Due to the engine geometry, the hot jets impact on a concave wall. This study is justified by the fact that few literature exists on the subject, at least for high Mach number conditions. Moreover, in order to get experimental results accounting for the complexity of the real configuration, one has to reproduce as far as possible the design of the industrial injection system. A preliminary bibliographical analysis [1, 11] has pointed out the relevant parameters governing the heat transfer in jet impingement for experimental devices presenting some similarities with the present configuration. Although the effects of the Reynolds or Prandtl numbers have been well documented, other parameters, such as the distance between the nozzles and the impact wall, the wall curvature or the Mach number have to be investigated. The study has then been divided in two parts: in a first step, low Mach number have been studied in order to compare with the literature on the subject. Then, the study has been carried out in the real industrial configuration, with Mach numbers about 0.9. The present paper is hinged as follows: chapter 2 presents the experimental set-up including the two injection systems (low and high Mach number) and the measurement means. Chapter 3 presents the results and a short discussion. Then a brief conclusion and future prospects end the manuscript. 2. Experimental set-up An overview of the experimental set-up is presented in Figure 1. The test section is made up a round pipe of diameter 100 mm providing air at flow rates ranging from 0.15 to 3 kg/s at a generating pressure of 10 bar. The air can be heated before entering the test section by means of a 570 kW electric heater. A system of manual and control valves ensure the required flow rate. Two sensors record the flow pressure and temperature. The test section length (several tens of pipe diameter) has been designed to ensure the flow stability. The injection system is mounted on a diffuser. Moreover, a row of honeycombs breaks the large eddies, ensuring by this way a low turbulence level in the inlet of the injection system.