As mentioned in Part 11, a calibration study of the wave pole is recom- 

 mended, but for a new stereo study, it is recommended that the design of the 

 wave pole be altered along the lines suggested by H. G. Farmer. 



At or near the same time that the stereo and wave pole data are taken, 

 it might be advisable to take records with anairborne altimeter as developed 

 at the U. S. Navy Hydrographic Office and with shipborne wave recorders in- 

 stalled on several different types of vessels. The airborne altimeter could 

 be flown at a number of different headings and the ships could be operated 

 both hove to in head seas and on polygonal patterns as described by Cart- 

 wright, This would require an advance forecast of a stationary state for at 

 least four hours, but this should not be too difficult to achieve. 



The wave pole data at the present time appear to be the only data 

 capable of reproducing the higher frequencies correctly, and such data 

 would still be needed. With stereo data, wave pole data, airborne altimeter 

 data, and shipborne recorder data it will be possible to make exhaustive 

 cross checks of the calibrations and responses of all the instruments and 

 to study the relative utility of each. 



With such exhaustive measurements of the sea state, additional data 

 of interest to naval architects and electrical engineers could also be ob- 

 tained at the same time. This would permit their theories and calculations 

 to be based on a firm foundation consisting of adequate knowledge of the 

 state of the sea at the time of their observations. 



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