Microphysical Properties of Artificial and Natural Clouds and Their Effects on UH-1H Helicopter Icing
Abstract
Natural and artificial icing tests were conducted form 22 January to 22 February 1979 in the vicinity of St. Paul, MN with follow-on natural tests conducted from 26 February to 21 March 1979 in the vicinity of Syracuse, NY. A total of 6.7 hours were flown in the artificial environment and 7.8 hours in the natural environment. Artificial conditions were tested at liquid water content (LWC) range of 0.25 to 0.90 gm/m to the 3rd power with a temperature range of - 10 to -20 degrees C. Natural conditions were encountered at LWC range of 0.06 to 0.23 gm/m to the 3rd power and a temperature range of -2.5 to -22 degrees C. Tests were conducted to determine the feasibility of operational deployment of a partial ice protection system consisting of electrothermally heated windshields, a sensitive outside air temperature (OAT) system, a LWC indicator and associated electrical changes. The test aircraft was a JUH-1H helicopter equipped with electrothermally decided blades as a safety device and laser nephelometers which were used to quantify the microphysical properties of the test environment. It was determined that the artificial environment (Helicopter Icing Spray System (HISS)) was not an adequate simulation in its present configuration. This was due in part to the large droplet size, heterogeneous characteristic of the plume and concentration of large droplets in the lower portion of the plume. It was also determined that the partial ice protection system did not increase the operational capability of the UH-1H helicopter and that LWC is not an adequate indication of icing severity.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1979
- Accession Number
- ADA084633
Entities
People
- Grady W. Wilson
- Ralph Woratschek