Proceedings Of The Marine

FAL 2012

Proceedings magazine is a communication tool for the Coast Guard's Marine Safety & Security Council. Each quarterly magazine focuses on a specific theme of interest to the marine industry.

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Audio Evidence Investigators knew that Cornell University's Laboratory of Ornithology had been collecting and researching the migra- tion of right whales using National Oceanic and Atmospheric Administration's (NOAA) acoustic buoys. These acoustic buoys are located throughout Massachusetts Bay to record and track the underwater vocal sounds of the marine mammals, so the investigators requested audio recordings for the night of Jan. 2 to 3, 2009. U.S. Navy Undersea Surveillance Analysis The 19 marine autonomous recording units (MARUs) deployed underwater in a hexagonal pattern in the bay gave investiga- tors a wide range of information for analysis. Analysis of the closest buoys to the wreck location revealed several sounds of interest. Buoy 4 first detects a loud sound, designated as aural transient event (ATE) 1, lasting 2.5 seconds at 12:07:12 a.m.; every other buoy records this, too. A second, moderately loud sound (ATE 2), lasting less than one second, is first recorded by buoy 4 at 1:12:33 a.m. and then is recorded by buoys 5, 12, and 13. Only buoy 4 detects a third, faint sound (ATE 3), lasting less than 3 seconds, at 1:20:20 a.m. Sector Boston Investigators provided the NOAA audio files to U.S. Navy Commander Undersea Surveillance (CUS) intel- ligence analysts. The CUS analyzed the audio files from Jan. 2 to 3, 2009 as well as 161 hours of audio files from eight periods in December 2008, when the F/V Patriot had operated in the same general area of Stellwagen Bank. According to the CUS, every engine's revolutions per minute (rpm) create a unique underwater sound signature, much like a fingerprint. Reprinted with permission. The CUS performed an analysis of the audio files and was able to conclusively identify the acoustic signature of the F/V Patriot and the tugboat (under investigation due to its close proximity to the Patriot during its transit). Additionally, the CUS was able to determine the fishing vessel's typical operating profile during fishing evolutions. Most significantly, the CUS created a detailed timeline of the F/V Patriot's final voyage based on the measured engine rpm of her main propulsion diesel engine. The Navy analysis detected an alternating current auxiliary motor from the Patriot starting at 8:53 p.m. on January 2, 2009. This motor runs at approximately 3,400 rpm until 1:06:11 a.m. on January 3, 2009, when it slows by 18 rpm over the next FDXVH RI WKH YHVVHO FDSVL]H ZDV SRVVLEO\ D VWDELOLW\ IDLO- XUH FUHDWHG E\ D FRPELQDWLRQ RI IDFWRUV DQG LQLWLDWHG E\ WKH OLIWLQJ RI WKH FRG HQG RI WKH QHW RII WKH GHFN 8QIRUWXQDWHO\ WKH ORVV RI VWDELOLW\ KDV EHHQ LGHQWLÀHG DV WKH URRW FDXVH RI PDQ\ FRPPHUFLDO ÀVKLQJ YHV- VHO FDVXDOWLHV ,W LV DSSDUHQW WKDW DV ÀVKHUPHQ PDNH PRGLÀFDWLRQV WR LQFUHDVH WKH HIÀFLHQF\ RI WKHLU YHV- 10 Proceedings Fall 2012 VHOV PRVW DUH XQDZDUH WKDW WKHLU LPSURYHPHQWV PD\ KDYH GUDVWLFDOO\ DOWHUHG WKH YHVVHO·V FHQWHU RI JUDYLW\ GLVSODFHPHQW DQG VWDELOLW\ FKDUDFWHULVWLFV $IWHU \HDUV RI XQGRFXPHQWHG YHVVHO PRGLÀFDWLRQV ZLWKRXW D VWDELOLW\ DQDO\VLV PDQ\ YHVVHOV PD\ EH RQH ´SHUIHFW VWRUPµ RI VKLIWLQJ ZHLJKW DZD\ IURP D FDWD- VWURSKLF HYHQW www.uscg.mil/proceedings

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