suggesting design changes to the manufacturer through BuShips 

 to correct such dif f icult ies „ This work required the closest 

 cooperation of field engineers, manufacturers, laboratories 

 and I\ T aval officials 



Field engineers "put out thousands of fires/' soldered 

 r.iany connections and made other emergency adjustments, but 

 their fundamental job was to improve equipment „ If a tube 

 burned out they would fix it, but they were more concerned 

 with determining from circuit design why the tube burned out. 

 They went to the crux of difficulties to determine how the 

 manufacturer could alter or improve the design or production 

 o f e qu ipme nt 



The Group's modifications of the Bearing Deviation Indi- 

 cator (BDI) is a r;cod example of detecting difficulties. The 

 BDI was developed after echo ranging gear ? and the first units 

 were ineffective because the power transformer produced a 

 60 cycle hum, A field engineer discovered the hum could be 

 reduced by relocating certain components in the equipment. 

 His modifications were sent to BuShips and later were pub- 

 lished in BuShips' official radio installation bulletin (RIB). 



To detect fundamental equipment difficulties, a variety 

 of experience and specialization was often necessary . For 

 instance, one field engineer who was an experienced mechanical 

 engineer had specialized in ASW Ordnance „ He was assigned to 

 a destroyer escort to determine why a hedgehog (Marl: 10 

 Projector) was difficult to train under sea conditions when 

 fully loadedo He discovered that faulty lubrication of the 

 trunnion bearings under full load was causing an increase 

 in friction o He suggested minor modifications in the 

 lubricating points „ His recommendations were accepted by 

 the Bureau of Ordnance and distributed to the fleets as 

 ordnance alterations , 



Familiarity with all ASW devices was also necessary. 

 In some cases, separate ASW devices, designed to operate 

 integrally with other shipboard equipment did not always 

 work as expectedc For instance, one model of echo ranging 

 gear when connected would not produce a trace on the re- 

 cording paper of the range recordor to permit adjustment 

 (no trace to zero zero), The range recorder was used fox 

 dropping depth charges and when not in proper adjustment 

 would have range errors ci 20 yards or more, A trace was 

 needed to determine the range accurately. Field engineers 

 detected the inadequacies, put the equipment in proper 

 operation, and sent suggestions for modification of the 



