218 OCEANOGRAPHY IN THE UNITED STATES 



plitudes and accelerations of ship motions in roll, pitch, and heave, 

 together with the hull strains, under different sea conditions. 



The wave patterns are measured by this shipborne wave recorder 

 [slide 7 — shipborne wave recorder]. It measures the instantaneous 

 height of the water alongside the ship and corrects for ship motions 

 by double integration of the acceleration. 



To measure sea conditions clear of the influence of the ship, the 

 model basin has developed a cheap expendable wave recorder [slide 

 8 — splashnik wave recorder]. The vertical motions of the buoy are 

 telemetered to the ship by a miniature frequency modulated radio 

 transmitter in the buoy. 



Another oceanographic instrument [slide 9 — oceanographic survey 

 instrmnent] being developed here is designed to measure very ac- 

 curately ocean currents at great depths, both in speed and direction, 

 together with the water pressure and temperature. The ability to 

 measure water salinity and the speed of sound at various depths down 

 to 10,000 feet will next be incorporated. 



This ship model representing the J/fl^n'^er class [slide 10 — segmented 

 Mariner model for hull strains] has been cut into sections and held 

 together by a flexure beam along the keel. When the model is tested 

 in waves, the bending and shear forces are measured which then indi- 

 cate the hull strains to be expected under various sea conditions. 



Full scale measurements of hull strains are made in merchant and 

 naval ships at sea, such as in the aircraft carried Essex here shown 

 in the roaring 40's [slide 11 — U.S.S. Essex entering the roaring 40's]. 



Oceanographic research, both basic and applied, creates masses of 

 scientific data highly time consuming to analyze. Here in the Ap- 

 plied Mathematics Laboratory of the David Taylor Model Basin high- 

 speed general-purpose digital computers [slide 12 — high-speed 

 computer IBM 704] save thousands of man-years in data reduction. 



Whereas our present computers operate at speeds up to 15,000 multi- 

 plications per second, there is being developed by the Bureau of Ships 

 for installation at the David Taylor Model Basin this computer [slide 

 13 — ultra-high-speed computer LAEC] which will make 100,000 

 multiplications per second. It will open up new frontiers in the 

 analysis of ocean wave spectra, the undersea transmission of sound, 

 and the behavior of ships and submarines at sea. 



Into such computers can be fed oceanographic observations, both 

 surface and subsurface, together with ship information, forming an 

 integrated source, fully automated, for sea surveillance [slide 14 — op- 

 erations research] . This is a part of operations research at the model 

 basin. 



The behavior of the sea surface is of direct interest in connection 

 with a water proximity vehicle [slide 15— water proximity airborne 

 vehicle] being developed by the Aerodynamics J^aboratory of the 

 David Taylor Model Basin, " Under this vehicle an annular air stream 

 is produced which greatly augments the lifting power when near the 

 water surface. 



The David Taylor Model Basin coordinates the acoustic measure- 

 ments [slide 1() — acoustic measurements on ships at sea] on all new 

 submarines, such as Skate and Skipjack. The submarine noises as 

 transmitted through sea water, against a background of sounds from 

 the ocean and marine life, are recorded through hydrophones to a 

 listening ship, by shore stations, and by other submarines. 



