The European Transonic Wind Tunnel - Testing at flight Reynolds numbers

The history of the establishment of ETW by France, Germany, the Netherlands and the United Kingdom is described briefly. The engineering concept is for a transonic cryogenic wind tunnel of high quality with a level of productivity appropriate for industrial use in the design and development of new civil and military aircraft projects. Commissioning followed erection of the tunnel on schedule and revealed only relatively minor problems requiring adjustment of the original design. Calibration tests started during commissioning and showed flow quality of the very high standard required by the specification. Early model tests, mostly carried out in collaboration with clients to validate the wind tunnel have shown good repeatability and have clearly indicated the predicted strong effect of Reynolds number on drag.