Airfoil trailing edge cooling construction

An airfoil for a gas turbine, comprising:

• a pressure sidewall and a suction sidewall, an interior cavity between the pressure and suction sidewalls for receiving cooling fluid in the cavity;
• the airfoil including a trailing edge having a plurality of exit ports in the pressure sidewall, and including a plurality of exit passages each having a channel height and communicating between the cavity and the exit ports;
• the pressure sidewall having a pressure side lip that leads to the exit ports of the exit passages, a cutback distance being defined as the distance between the tip of the trailing edge and the end of the pressure side lip;
• and
• the suction sidewall terminates at the trailing edge in a rounded portion in the shape in cross section of a circle, the trailing edge having in the region of its circular shape a trailing edge diameter, the rounded portion extends to the pressure sidewall including the exit ports in the pressure sidewall and beyond into the exit passages, thereby forming a curved bend in the exit passages adjacent the exit ports, and including an exit plenum where the cooling fluid diffuses and cools the airfoil trailing edge.