CG 47 CLASS ADVISORY NR 15-92
TACTAS LEVELWIND ASSEMBLY MOUNTING BOLTS
*** INACTIVE *** INACTIVE *** INACTIVE ***
REF/A/DOC/NAVSEA/85MAY16//
AMPN/NAVSEA DWG 807-5035351 - INSTALLATION CONTROL DWG FOR
OK-410(V)1/SQR LEVELING ASSEMBLY.//
RMKS/1. THIS ADVISORY ALERTS ALCON TO A POTENTIAL PROBLEM WITH
THE AN/SQR-19(V) TACTAS LEVELWIND ASSEMBLY MOUNTING HARDWARE.
2. BACKGROUND. INVESTIGATION INTO THE AFTER EFFECTS OF MINE
SHOCK ON USS PRINCETON REVEALED THAT THE MOUNTING BOLTS FOR THE
LEVELWIND ASSEMBLY WERE NOT IN ACCORDANCE WITH REF A
REQUIREMENTS. SPECIFICALLY, SHOCK CAUSED THE LEVELWIND ASSEMBLY
TO TEAR FREE OF ITS OVERHEAD FOUNDATION. NOTE 14 OF REF A STATES
THAT MOUNTING BOLTS ARE TO BE HEX 0.750-10 UNC-2A, MIL-S-1222G
GRADE 500 (NICKEL ALLOY, 90 KSI STRENGTH), USED WITH SELF-LOCKING
NUTS 0.750 UNC-3B MS16228-12C AND FLAT WASHERS 0.750 MS15795-422.
BOLTS SHOULD BE TORQUED TO 160 FT-LB (LUBRICATED). THE BOLTS
USED ON BOARD PRINCETON WERE GRADE TWO.
3. ACTION. CG 47 CLASS SHIPS SHALL INSPECT THE LEVELWIND
ASSEMBLY MOUNTING BOLTS TO VERIFY THAT THE PROPER BOLTS WERE
USED. GRADE 500 BOLTS ARE IDENTIFIED BY THE LETTER K PRECEDED
AND FOLLOWED BY DOTS (ALTERNATIVELY, THEY MAY BE MARKED NI-CU-AL)
PERMANENTLY MARKED ON THE BOLT HEAD TOGETHER WITH THE
MANUFACTURERS SYMBOL AND LOT NUMBER. NUTS ARE SIMILARLY MARKED ON
THE NUT FACE. IF IMPROPER BOLTS ARE FOUND, FORM 4790/2K SHOULD
BE PREPARED FOR THEIR REPLACEMENT DURING THE NEXT SRA.
4. FOR COMNAVSURFLANT/COMNAVSURFPAC - RECOMMEND CG 47 CLASS
SHIPS BE TASKED TO CARRY OUT THE REQUIREMENTS OF PARA 3 ADVISING
TYCOMS OF RESULTS. IN ORDER TO SATISFY CANCELLATION CRITERIA FOR
THIS ADVISORY, REQUEST TYCOMS COORDINATE RESPONSES AND FORWARD
RESULTS TO ORIGINATOR.
5. FOR SUPSHIP BATH/PASCAGOULA - ENSURE THAT SUBJECT ASSEMBLY
FOR SHIPS NOW UNDER CONSTRUCTION IS IN ACCORDANCE WITH THE
REQUIREMENTS OF REF A.
6. THIS ADVISORY HAS NO IMPACT ON EOSS, CSOSS, PMS, OR TECHNICAL
DOCUMENTATION. IT WILL BE CANCELLED WHEN PROPER INSTALLATION HAS
BEEN VERIFIED ON ALL SHIPS.
7. POC IS MR. N. S. SMITHSON, PMS400F43B, DSN 332-5981 OR COMM
(703) 602-5981. TECHNICAL POC IS R. BROWN, PMS400B32B, DSN
332-7090 OR COMM (703) 602-7090.//
CG-47