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RATUZYUW RUCOMCB2572 2721823-UUUU--RUCBTFA.
ZNR UUUUU ZUI RULSSBG0122 2721407
R 291407Z SEP 98 ZYB PSN 848885L41
FM PEO MINEWAR WASHINGTON DC//PMS407//
TO RUCBTFA/COMNAVSURFLANT NORFOLK VA
//N35/N43/N431/N434/N431B3/N437/N652//
INFO RULSSBG/PEO MINEWAR WASHINGTON DC//PMS303/407//
RUBDPLA/COMINEWARCOM C1//
RULSAMN/NAVSEALOGCEN MECHANICSBURG PA//05/051//
RUDJABT/SWOSCOLCOM NEWPORT RI//63//
RHWISAZ/NAVUNSEAWARCENDIV KEYPORT WA//434/448//
RUCTMGB/NAVSURFWARCEN COASTSYSTA PANAMA CITY FL//A05L/AII//
RUCBFAJ/COMSURFWARDEVGRU LITTLE CREEK VA//N3//
RULSSEA/COMNAVSEASYSCOM WASHINGTON DC//MSG_CENTER//
BT
UNCLAS//N04000//
MSGID/GENADMIN/PEO MIW PMS407//
SUBJ/MCM 1 CLASS ADVISORY 17-98, AN-SQQ-32(V) SONAR SPURIOUS
/EMERGENCY TOWED BODY (TB) HAUL-IN//
POC/T. MILLER/CDR/PEO MINEWAR (PMS407T)/-/TEL:(703)602-2910X429
/TEL:DSN:332-2910X429//
RMKS/1: PURPOSE. PROVIDE GUIDANCE REGARDING AN/SQQ-32(V) SONAR
SPURIOUS EMERGENCY TOWED BODY HAUL-IN CONDITION.
A. THIS ADVISORY APPLIES TO MCM 1-14.
B. THIS ADVISORY DOES NOT AFFECT LOGISTICS.
2. BACKGROUND: USS PIONEER AND USS GLADIATOR REPORTED SUDDEN
TOWED BODY (TB) EMERGENCY RETRIEVALS WHICH HAVE IMPAIRED MINEHUNTING
OPS.
A. HEIGHT ABOVE BOTTOM (HAB) SAFETY FEATURE OF AN/SQQ-32(V)
SONAR PROTECTS TB FROM POTENTIAL BOTTOM COLLISION DURING VDS
OPERATIONS BY UTILIZING AUTOMATIC HAUL-IN FEATURE.
B. DESIGN UTILIZES A PRIMARY AND BACK-UP SYSTEM TO AVOID BOTTOM
COLLOSION. PRIMARY SYSTEM MEASURES TB HAB WHILE WITHIN 500 FEET OF
BOTTOM AND WILL INITIATE AUTOMATIC HAUL-IN IF TB BECOMES WITHIN 50
FEET OF BOTTOM. BACKUP SYSTEMS USES AN ALGORITHM THAT CALCULATES HAB
WHEN IN EXCESS OF 500 FEET (ALTIMETER IS "OUT OF RANGE" IN EXCESS OF
500 FEET) OR WHENEVER ALTIMETER IS OOC.
C. SAFETY FEATURE LOGIC INTERPRETS HAB IN EXCESS OF 500 FEET AS
ALTIMETER FAILURE AND REVERTS TO BACKUP SYSTEM. BACKUP ALGORITHM
UTILIZES PRESSURE SWITCH AND INPUT DEPTH FROM FATHOMETER TO CALCULATE
HAB. DEPENDING ON PROXIMITY OF TB WRT FATHOMETER, FATHOMETER WILL
READ TB AND PROVIDE ERRONEOUS BOTTOM DATA RESULTING IN EMERGENCY
HAUL-IN.
3. DISCUSSION: A SHALLOW WATER OVERRIDE (SWO) FUNCTION IS PROVIDED
IN VERSION SEVEN POINT ZERO (FC 38) OF THE AN/SQQ-32 SOFTWARE. THIS
FUNCTION IS DESIGNED TO BE USED WHEN MISSION OR ENVIRONMENTAL
CONDITIONS REQUIRE TB TO BE PLACED WITHIN 50 FFET OF BOTTOM. SWO
CAN BE SELECTED OR DESELECTED AT ANY TIME DURING SONAR OPS.
APPROPRIATE USE OF THIS FEATURE WILL EFFECTIVELY ELIMINATE ERRONEOUS
EMERGENCY HAUL-IN OCCURRENCES. SINCE FALSE HAUL-IN PROBLEMS ONLY
OCCUR WHEN GREATER THAN 500 FEET HAB, THE RISK OF BOTTOM COLLISION
IS SIGNIFICANTLY REDUCED. HOWEVER, SWO SHOULD BE DESELECTED
WHENEVER TB IS IN CLOSE PROXIMITY TO THE BOTTOM (WITHIN ALTIMETER
RANGE) UNLESS OPERATIONAL CONDITIONS DICTATE OTHERWISE.
4. ACTION:
A. UPON INSTALLATION OF FC 38, SHIPS FORCE UTILIZE SWO FUNCTION
DURING SONAR OPS REMEMBERING TO DESELECT SWO OVERRIDE WHEN TB IS
WITHIN ALTIMETER RANGE (INSIDE 500 FEET HAB).
B. ORIG WILL CONTINUE TO MONITOR COMPLETION OF FC 38 AS WELL AS
TRACKING ITS EFFECTIVENESS. FOLLOW UP STATUS WILL BE PROVIDED TO
ALCON AS REQUIRED.
6. LOGISTICS: THIS ADVISORY DOES NOT AFFECT LOGISTICS.
7. CANCELLATION: THIS CLASS ADVISORY SHALL REMAIN IN EFFECT UNTIL
CANCELLED OR SUPERSEDED BY ORIG.//
BT
#2572
NNNN
# N431 (ACT)
# N434 N65 N8 N412B
# SDO PCMT N51 N432 N431B N43 N412 N33 N3 N02X MSG-CTR N13
# N6 N63 N81 N82 N411 DSO N3A
!!! /D7/18/6/3/MCM/03400A/
!!! /D7/18/12/14/CLASS/01443A/
!!! /D7/19/2/9/EMERGENCY/00001D/
!!! /D7/22/47/9/AN/SQQ-32/00002D/
!!! /D7/25/35/9/LOGISTICS/04000A/