CG-47


                    FFG 7 CLASS ADVISORY NR 04-93                               

                                                                                

         MK 36 DECOY LAUNCHING SYSTEM(DLS) POWER SUPPLY                         

            CIRCUIT BREAKER WITH AUXILIARY SWITCH                               

                                                                                

 REF/A/RMG/NCSL PORTSMOUTH/121505ZFEB93/-/NOTAL//                               

                                                                                

 REF/B/RMG/NSWC ORD LOUISVILLE/081530ZMAR93/-/NOTAL//                           

                                                                                

 NARR/REF A IDENTIFIED A FFG 7 CLASS MK 36 DECOY LAUNCHING SYSTEM               

 SAFETY PROBLEM.  REF B REQUESTED THAT NAVSEA RESOLVE                           

 CONFIGURATION CONTROL PROBLEM WITH CIRCUIT BREAKERS CONTROLLING                

 POWER TO LAUNCHERS ONE AND TWO.//                                              

                                                                                

 POC/A. FINAZZO/CIV/PMS330TS2/WASHINGTON DC/TEL:DSN 332-1305                    

 /TEL:(703) 602-1305//                                                          

                                                                                

 RMKS/1. THIS ADVISORY PROVIDES GUIDANCE FOR VERIFYING                          

 INSTALLATION OF CORRECT CIRCUIT BREAKER, REPLACEMENT PROCEDURES                

 IF REQUIRED, AND INTERIM SAFE MAINTENANCE PROCEDURES FOR MK 36                 

 DLS LAUNCHERS ONE AND TWO.                                                     

                                                                                

 2.  BACKGROUND.  REF A IDENTIFIED A MK 36 DLS SAFETY PROBLEM                   

 WHICH COULD RESULT IN INADVERTENT DECOY LAUNCHING.  SOME FFG 7                 

 CLASS SHIPS DO NOT HAVE THE CORRECT CIRCUIT BREAKERS INSTALLED                 

 FOR LAUNCHERS ONE AND TWO.  THE PROPER CIRCUIT BREAKER NOT ONLY                

 FEEDS THE MK 160 PWR SUPPLY OF EACH LAUNCHER BUT ALSO CONTAINS AN              

 INTERNAL AUXILIARY SWITCH THAT OPENS THE 28VDC BACK-UP BATTERY                 

 CIRCUIT WHEN THE BREAKER IS IN THE OFF POSITION.  INSTALLATION OF              

 A CIRCUIT BREAKER WITHOUT AN INTERNAL AUXILIARY SWITCH CREATES                 

 THE POTENTIAL FOR INADVERTENT LAUNCH WHILE PERFORMING SYSTEM                   

 MAINTENANCE.  AS REQUESTED REF B, THE FOLLOWING GUIDANCE IS                    

 PROVIDED TO IDENTIFY AND CORRECT THE PROBLEM.                                  

                                                                                

 3.  ACTION.                                                                    

                                                                                

     A.  EXAMINE SUSPECT CIRCUIT BREAKERS FOR LAUNCHERS ONE AND                 

 TWO IN POWER PANEL 01-183-2 LOCATED IN AIRNAV/ECM ROOM                         

 (01-180-0-Q).  PART NUMBER FOR CORRECT BREAKER IS CAT. NO.                     

 ETN2750-10, WHICH IS STAMPED ON THE BREAKER.  IF UNABLE TO                     

 DETERMINE P/N FOR BREAKERS, CHECK THE MK 160 METER FOR 28V                     

 BATTERY CIRCUIT WITH BREAKER IN OFF POSITION. METER SHOULD READ                

 ZERO VOLTS WITH CORRECT BREAKER INSTALLED.                                     

                                                                                

     B.  IF INCORRECT BREAKER IS INSTALLED, PROCURE CORRECT                     

 BREAKER LISTED ABOVE AND 30 FEET OF TYPE F3 CABLE.  THE ORDERING               

 DATA FOR THE CIRCUIT BREAKER WITH AN AUXILIARY SWITCH IS                       

 AQB-A101, 15A ELEMENT, APL NO. 14032175, NSN 5925-01-139-3139.                 

 WITH 28VDC AND 440VAC POWER SECURED AND PROPERLY TAGGED-OUT,                   

 REMOVE EXISTING CIRCUIT BREAKER AND INSERT CORRECT BREAKER WITH                

 AUXILIARY SWITCH. REMOVE AND DISCARD 2-CONDUCTOR CABLE RUNNING                 

 FROM BREAKER TO MK 160 POWER SUPPLY.  RUN NEW TYPE F-3 CABLE FROM              

 BREAKER TO MK 160 POWER SUPPLY.  USE TWO CONDUCTORS TO RECONNECT               

 TWO POLES OF THE BREAKER TO THE MK 160 440VAC SUPPLY (THIRD POLE               

 OF THE BREAKER IS NOT USED). USE THE TWO REMAINING CONDUCTORS TO               

 CONNECT THE AUXILIARY SWITCH (NORMALLY OPEN CONTACTS) OF THE                   

 CIRCUIT BREAKER TO THE 28VDC BATTERY CIRCUIT WITHIN THE MK 160                 

 POWER SUPPLY.  ONE SIDE OF NORMALLY OPEN CONTACTS OF AUXILIARY                 

 SWITCH SHOULD BE CONNECTED TO THE POSITIVE SIDE OF THE BATTERY,                

 COMMON SIDE OF AUXILIARY SWITCH SHOULD BE CONNECTED TO TB4-7 OF                

 MK 160 POWER SUPPLY.  UNUSED WIRE FROM AUXILIARY SWITCH SHOULD BE              

 SECURED INSIDE POWER PANEL.                                                    

                                                                                

    C. IF POWER MUST BE SECURED TO PERFORM MAINTENANCE ON                       

 LAUNCHERS 1 OR 2 PRIOR TO INSTALLATION OF CORRECT BREAKER, ENSURE              

 BATTERY LEAD IS DISCONNECTED IN ADDITION TO DISABLING THE 440VAC               

 POWER VIA THE EXISTING BREAKER.                                                

                                                                                

 4.  FOR COMAVSURFLANT/COMNAVSURFPAC - RECOMMEND FFG 7 CLASS SHIPS              

 BE TASKED TO COMPLY WITH PARA 3 ACTION AT EARLIEST OPPORTUNITY.                

 REQUEST ALL SHIPS REPORT FINDINGS AND, IF REQUIRED, COMPLETION OF              

 CORRECTIVE ACTION TO NAVSEA PMS330, INFO TYCOM, NSWC ORDSTA                    

 LOUISVILLE (CODE 90F1) AND LBNSY (CODE 270.2).  INSTALLATION OF                

 CORRECT BREAKER WILL BE VERIFIED AS PART OF FUTURE INSTALLATIONS               

 OF SHIPALT FFG7-176K, MK 36 DLS EXPANSION.                                     

                                                                                

 5.  THIS ADVISORY HAS NO IMPACT ON EOSS, PMS, CMP OR TECHNICAL                 

 DOCUMENTATION.  IT WILL BE CANCELLED WHEN ALL FFG 7 CLASS SHIPS                

 HAVE REPORTED COMPLETION OF PARA 3 GUIDANCE.//