Abstract: A gas turbine engine has a low cost combustor liner cooling system combining the benefits of high internal heat removal with improved film cooling by employing a large number of strategically positioned, laser-drilled cooling passages. Cooling air flows through these specially tailored passages to absorb heat from the liner prior to injection as a protective film on the interior surface. The passages are set in staggered rows on a thickened portion of the liner and have a rough internal heat transfer surface and an exit with a steep injection angle to evenly distribute the cooling film along the interior surface of the liner.