A LIQUID WATER CONTENT METER

THERE IS GROWING EVIDENCE THAT UNDER VERY HEAVY RAINFALL RATES, AIRFOILS WILL SUFFER AERODYNAMIC PERFORMANCE PENALTIES. RAINFALL RATES AND LIQUID WATER CONTENT (LWC) ARE DIRECTLY CORRELATED. NASA TESTING PLANNED FOR LATER THIS YEAR WILL ATTEMPT TO QUANTIFY THESE PENALTIES AS A FUNCTION OF LWC TO DETERMINE AT WHAT LEVEL LWC INDUCED PERFORMANCE DEGRADATION PRESENTS A SERIOUS HAZARD. IT IS CURRENTLY NOT KNOWN FOR WHAT PERIOD OF TIME OR AT WHAT ALTITUDE, HIGH LWCS IN THE ATMOSPHERE ARE ANTICIPATED, SINCEINSTRUMENTATION TO MAKE THESE MEASUREMENTS HAS NOT BEEN DEVELOPED. THIS PROPOSAL INVESTIGATES THE FEASIBILITY OF DEVELOPING AN AIRCRAFT-MOUNTED LWC PROBE WHICH WILL DETERMINE THE LWC FROM MEASUREMENTS OF WATER FILM THICKNESS,ENABLING THE PROBABILITY OF A HAZARD CAUSED BY HEAVY RAINFALL RATES TO BE DETERMINED.