INTRODUCTION 



This paper presents a summary of some of the oceanographic data 

 taken with a torpedo-like instrument carrier. The details of the complete 

 system will be presented elsewhere. However, generally, the device is 

 launched from a surface vessel (Fig 1) and dives to one of several preset 

 pressure levels. It runs for 4 to 6 hours at 6 knots and is capable of oper- 

 ation down to 14, 000 feet. An acoustic system gives position with respect 

 to the surface ship and accepts commands to change depth and heading 

 during the run. 



Figure 2 gives a list of the variables recorded on the operations 

 reported here. Thermistor number 1, located on the nose, is recorded 

 12 times per second. Thermistor number 2, located on the tail, is record- 

 ed three times per second. These sensors have a time constant of 40 ms. 

 The Gulton Thermometer is a quartz oscillator having a time constant of 

 several seconds and is located on the nose. Sound velocity, as noted here, 

 is recorded 12 times per second. This instrument is seldom operated 

 below 1000 m depth since the resolution of recording, 0. 1 m/sec is insuf- 

 ficient to detect the variations normally observed. The data are recorded 

 digitally on magnetic tape and can be played directly into an IBM computer 

 or converted back to an analog voltage for direct recording. The last 

 column of Figure 2 lists the resolution per bit of the digital recordings. 



DATA DESCRIPTION 



The data reported here were taken on three cruises. The first in 

 March 1964 was about 230 miles west of San Diego in 2000-fathom water. 

 The second cruise was near Oahu in the Hawaiian Islands as shown in 

 Figure 3. This was one week in September 1964. The third cruise in 

 March of this year was in the Southern California area and near the island 

 of Guadaloupe. Figure 4 shows some of these run trajectories. As can be 

 seen, some of these runs have 90° turns which allow the determination of 

 two components of the horizontal gradient. 



The next few figures are presented in order to give a general impres- 

 sion of the results obtained in operations of this type. Figure 5 is a photo- 

 graph of the analog playback of a run at 30 m depth. Eighteen nautical 

 miles of record are represented along the horizontal scale. The upper 

 temperature trace was off scale and limited during portions of the large 

 excursions at the beginning and end of the record. With this exception, 

 temperature and sound velocity "track" very closely. As can be seen, the 

 depth excursions are less than one meter. A vertical profile taken one 



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