Experience with the Infrared System for Transition Detection on A320 Fin Hybrid Laminar Flow Experiment

Abstract

During the flight experiments the infrared system and the infrared data acquisition system worked properly. Some minor problems were solved during the campaign. Taking into account that in flight experiments every data point takes 5 minutes, the movement time of 40 seconds for the infrared-camera positioning is too long. There are also problems to stabilize the aircraft for such a long time. The overall time for taking the three pictures of both sides should not exceed half a minute. The fairing of the infrared-camera was much larger than necessary,a smaller one probably would cause less problems with elevator buffet at high Mach numbers. With the infrared system (as it was built into the A320) a real measurement of laminar-turbulent transition on the fin could have been possible, but laminar flow was not present as known in advance.