100 THE NAVY OCEAN SCIENCE PROGRAM 



As the requirements for the determination of size, shape, and 

 speed of targets increase, acoustic systems of increased emgular 

 resolution, time resolution, and sensitivity will be needed. Since 

 smaller segments of the ocean will be investigated in greater 

 detail, scattering and reverberation phenomena must be known 

 to higher precision. This implies more knowledge of scattering 

 mechanisms at the ocean boundaries and at ocean structure 

 discontinuities. The statistics of biological organism distribution 

 must be improved, and methods of prediction of changes in this 

 distribution made available. 



Acoustics is considered as a hand tool of oceanography. Start- 

 ing with the echo sounder and two abortive attempts at radio- 

 acoustic ranging, acoustical systems have been employed in 

 oceanography to measure distance underwater. Various systems 

 now exist for submerged navigation that depend on measure- 

 ment of acoustic travel times. The depths of tow nets and other 

 oceanographic instruments are commonly telemetered acoustical- 

 ly or measured by means of an inverted echo sounder mounted 

 on the instruments. The height of cameras above the sea floor 

 is commonly measured by means of sound echoes. Underwater 

 acoustic telephony has been an established means of communica- 

 tions for years. As design and reliability improve, all of these 

 methods are coming into wider use, especially among oceanog- 

 raphers with no previous experience with acoustics. The trend 

 is still developing and will probably be far more characteristic 

 of the next ten to fifteen years in oceanography than over the 

 past twenty. Although much experimentation is needed, and 

 although several new concepts will be developed, the present 

 requirement is for reliable, stable instruments. 



SCIENTIFIC PLATFORMS 

 AND INSTRUMENTATION 



The task of conducting research on the oceans is a difficult 

 one, and our present paucity of knowledge about this environ- 

 ment stems, in large measure, from the lack of adequate equip- 

 ment in the past. The Navy's oceanographic shipbuilding pro- 



