<div class="htmlview paragraph">Effusion cooled combustor designs for gas turbine engines offer improvements over traditional cooling approaches. The effusion technique, also known as transpiration, or multi-hole, employs minute cooling passages through the wall to be cooled. Effusion cooling provides increased cooling effectiveness, enabling higher performance. Additionally, effusion cooling offers manufacturing benefits, due to its simplicity of design, which result in decreased cost. The design also provides many challenges due to the enormous number of cooling holes required in an effusion cooled component. Candidates for hole drilling, laser and electron beam drilling, are compared with respect to methodology, equipment, hole characteristics, and economics.</div>