Evaluation of the Helicopter Icing Module for TWI (Tactical Weather Information)

• Main Author: Luers, James K.
• Other Authors: DAYTON UNIV OH RESEARCH INST
• Format: Text
• Language: English
• Published: 1987
• Subjects: Snow; Ice and Permafrost; Helicopters; *ICE FORMATION; *WEATHER FORECASTING; ESTIMATES; FREEZING; GRIDS; MODULAR CONSTRUCTION; OBSERVATION; PRECIPITATION; RAIN; TACTICAL DATA SYSTEMS; Ice; permafrost
• Online Access: http://www.dtic.mil/docs/citations/ADA215056; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA215056

An evaluation was made of the Army's Helicopter Icing Modu le for Tactical Weather Information. The important features of the Helicopter Icing Module relate to its ability to estimate the severity of icing conditions. The severity of icing was assessed by evaluating three of the four submodules which contribute to the severity information. These submodules are a) the preliminary analysis which provides an estimate of negligible vs trace icing as a function of dew-point depression and temperature; b) the frontal analysis submodule which enhances the icing estimate based upon the proximity of the grid area to a front; c) an orographic submodule which further enhances the severity level as a result of the vertical motion induced by hilly terrain and; d) a freezing rain, freezing drizzle submodule which assigns severe or moderate icing conditions to the geographic region surrounding an observation of freezing precipitation. (sdw)