INTRODUCTION 



Flying logs from the stump to a landing area using a balloon is a relatively new 

 technique to minimize the environmental impacts of logging. Little data are available 

 on balloon logging production and the factors affecting production rates. 



This report presents the results of a 1973 time and motion study of a balloon 

 logging experiment in the Idaho Batholith. The results may be useful for foresters or 

 engineers estimating logging production rates, and for analyzing proposed balloon 

 logging operations. A data collection technique, a method of statistical analysis, 

 and the relative importance of different measured variables involved in balloon logging 

 studies are presented. These should help avoid the wasted time and effort which 

 normally occur when starting a study on any new logging system. It must be recognized 

 that these results are narrow in scope when one examines the wide range of variables 

 possible in terrain conditions, timber harvesting techniques, climate, logging set 

 configurations, volume of timber per acre, and log size, to mention a few. 



Details of the balloon logging system, timber harvest prescription, terrain 

 conditions, environmental constraints, and cost data are described in Forest Service 

 Research Paper INT-208, "Balloon Logging in the Idaho Batholith: A Feasibility 

 Study," by William S. Hartsog (1978). The paper provides valuable information on the 

 functioning of the balloon logging system, information necessary for understanding the 

 applicability of time and motion data. 



METHODS 



The first task of the time and motion study was to observe carefully the balloon 

 system operation and factors affecting production rates. Selection of variables to be 

 measured during the data collection phase was based on these observations. Time 

 required to complete a logging cycle (turn) was determined to be the dependent variable 

 since it indicated production and seemed to be affected by many of the other factors. 

 Turn time was partitioned into five elements. Since total turn time equaled the sum 

 of these five elements, all six are dependent variables. The dependent variables are 

 fully defined, along with the independent variables, in a later section. 



Data Sheets 



Data sheets were designed to collect information on those factors selected in the 

 initial observations; these were to serve as variables in a multiple regression analy- 

 sis. Three data sheets were used for collecting field data: Site/Terrain Information, 

 Yarding Data, and Scaling Data. The Site/Terrain Information sheets (fig. 1) were 

 used to record information pertinent to site description, site conditions, and the 

 logging subsystem (balloon yarding in this case) . Yarding Data sheets (fig. 2) were 

 used to record the time required for each element within the turn and other physical 

 measurements important to the study. Scaling Data sheets (fig. 3) were used to record 

 the measurements of each log so that volume and weight could be calculated for each 

 turn of the ballon yarding subsystem. For a detailed description of the data collection 

 methods, see the publication "Time Study Techniques for Logging Systems Analysis" 

 (Gibson and Rodenberg 1975) . 



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