The develoj of underwater flares as an aid In the de- 

 tection of submarines at night was undertaken at a time when 

 U-boats were operating in the comparatively shallow waters off 

 the Atlantic Coast of the United States „ Later p when the U- 

 boats ad been forced to retire to deeper waters where flares 

 would have been useless,, the project was dropped^ but not be- 

 fore a tragic accident had occurred on the night of 8 June 

 1942c Two Navy blimps participating in tests of underwater 

 flares collided,:. With the exception of one Naval officer, all 

 aboard were killed, including five 1IDRC scientists § Franklin Co 

 Gilbert of the New London Laboratory;; Israel Ph Tilles and 

 Arthur B, Wyse of the San Diego Laboratory? Laurence So Moyer, 

 special adviser to Division 6? and Charles Ro Hoover cf Divi- 

 sion B s which was cooperating in the underwater flare research 



Research on Roc kets „ 



In addition to its work for Division 6, the Hydrodynamics 

 Laboratory at California Institute of Technology also aided 

 Division 3 9 which was responsible for the development of rockets 

 The Laboratory carried out an extensive program of tests on 

 rocket characteristics Many of the troubles encountered in 

 rocket behavior developed during the burning of the propellant 

 charge o It was found that water tunnel measurements cf the 

 forces acting on the rocket body could be correlated with the 

 behavior cf the rocket during this initial period and could 

 be used to develop shapes that would have the desired perform- 

 ance characteristics,, The rockets for which model studies 

 wore made ranged in size from the Infantryman's bazooka to 

 the Ting Tim aircraft rocket with its diameter of nearly 12 

 inches 



Some cavitation studies were also made in conjunction 

 with these rockets since some of them were designed for use 



tinst underwater targets „ Most of the rockets studied were 

 of the fin-stabilized type 9 but it was also found that the 



;■ tunnel measurements were cf use in the design of spin- 

 stabilized rocketso The properties of several of 

 type of projectiles were investigated in the tunnel,, 



104 



