ABSTRACT This paper is an experimental investigation of the film cooling performance over a flat plate using transient liquid crystal measurements.Cylindrical hole with straight angle injection was used.Experiments were conducted at different blowing ratio (M=0.5 to 1.5) and different cooling channel Reynolds number (ReDh,c=10000, to ReDh,c=40000). All Experiments were conducted at constant hot gas Reynolds number and constant pressure ratio and.Film cooling Performance h (heat transfer coefficient) and η (adiabatic film cooling effectiveness are determined using the transient liquid crystal method combined with a numerical regression method to solve for the two unknowns). The results are discussed and compared to previously published literature.