USVI Public Records

Document text

1~~- I 7’ A D A 059 b55 TRANSPORTATION SYSTLMS CENTER CAMBRIDGE MASS F/S 13/10 OFFSHORE VESSEL TRAFFIC MANAGEMENT (OVTM) STUDY. VOLUME I. EXEC——ETC (U ) AUG 78 R BLAND. P KALAFUS . R WISLEOER I UNCLASSIFIED TSC—U5C6 78—11 1 USCG— D—55 78—VOL—1 NL I _ ______ H . H I t~ I.. ~~ ll~2.5 • U ~ IH ~ ~: ~22 I I I ~~~~~~~~~~~~ ITH~ OOI~~~~ . WilL25 llhI~. ffl~ o . MICROCOPY RESOLUTION TEST C~4~~T NA1lO~1A1 BUREAU OF STANDARDS ]963~E REPORT NO. CG-D-55-78 •~~ OFFSHORE VESSEL TRAFFIC MANAGEMENT (OVTM) STUDY Volume I — Executive Summary U.S. DEPARTMENT OF TRANSPORTATION ~~~~~~~~ . RESEARCH AND SPECIAL PROGRAMS ADMINIST RATION Transportat ion Systems Center Cambridge MA 02142 AUGUST 1978 FINAL REPORT DOCUMENT IS AV AILABLE TO THE U.S. PUBLIC THROUGH THE NATIONAL TECHNICAL INFORMATION SERVICE . SPRINGFIELD . VIRGINIA 22161 Prepared for U.S. DEPARTMENT OF TRANSPORTATION UNITED STATES COAST GUARD Off ice of Marine Environment and Systems Washington DC 20590 78 09 ~ 9 024 1~ ~ r a . _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ “ I NOTICE rh is technical study exam ines traffic managemen t al ternatives as a means to reduce or eliminate casual ties con tributing to pollution of the mar ine environmen t. Nothing contained in this report should be cons trued as affec ting or chang ing the Adminis tration ’s posit ion on offshor e cla ims in general or at the Third United Nations Con fe rence on the Law of the Sea in particular. NOTICE Th is doc ument is d issem inated under the sponsorsh ip of the U.S. Depar tment of T ranspo rtation in the interest of information exchange. The United States Governmen t assume s no liability for its contents or use thereof. NOTICE The United States Government does not endorse prod- uc ts or manufac turers. Trade or manuf ac turers ’ names appear herein solely because they are con- sidered essential to the objectives of this report. ~J~L W. . -.~ ~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~ ED1 I1U~ / ~ _ _ _ _ 7/— Z12~ ’ -_Z~ ( T. ChB)CSI k.p. ,t Docw~i.niation P.g. —‘ r~ Go •u~~.ni A.c.s . a., N. 3. Pano,~.n,’ . Co,.Io5 N.. ~~~ ~~~ D-55-78T\ ~~~~~~~JJ , . (~,/ 1. 1,1. .nd S,~bt.iI. __________ ~ FFSRORE VESSEL TRAFFIC MANAGEMENT ( ovTN) STUDY ( ~~~~~~~~~~~~~~~~~ ( ~~ — ~~ _ 6. P.,f.,~~~~~O, .na,.,a.., Cod . Volume I ‘ Executive Su~ nary~ - _________________________ — S. P. rf.~~in, O~ganiz.ti.n R.p.~t No. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ a l * DOT-TSC-CG-78-1l ,I~ \,~ /~ ‘, ~ IS. War), Unit N.. (TRA IS) CG8 16/R8007 U.S. Department of Transporta tio Research and Special Programs Admin~~~~~ ’a~~~~n. ( I n. CO.,*,OCt O, G,ant NO. Transportation Systems Center Cambrid ge MA 02142 ~. T~~~~ V4 UI~~H1P.~.,d-~ --.,.j4 12. Sp.n.. , ~.,5 Ag.øcy Horn , and Add r •ss , . / J__ ______ _ . U. S. Department of Transportation ~~~~~~~~~~~~~~~~~~~ I ç 1 Final 77.4—Jun $78~. / United States Coast Guard _ _ _ _ _ _ _ _ _ Off ice of Marine Environmen t and sys tem~~~~~~~~~! ~~~ Washington DC 20590 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ IS. Supp l.rn.ntory Not.. *F. Frankel , D. Prerau , S. Protopapa , 0. Clater , J. LoVecchio , and R. Wiseman 16. Ab.t..et N ‘ ~‘The objectives of the study were : (1) to anal yze the causes of tanker and other vessel casualties that could potentially result in oil pollution , and (2) to evaluate various alternative vessel traffic management systems and techniques for the preven- tion of oil-polluting casualties in the U.S. offshore waters. The geographical areas of interest are the waters from the U.S. coast out to 200 NM around the contiguous 48 States , Hawa ii , Puerto Rico , the Virgin Islands and Alaska , except the area north of the Aleutian Islands. Three types of casualties are addressed in the study: groundings , collisions , and rammings. Vessels included in the study are tank vessels (tankers and tank-barges) over 1,000 gross tons. The analysis of the causes of tank vessel casualties is performed mainly with the Coast Guard Merchant Vessel Casualty Report (MVCR) data base covering the period from July l9’l to October 1977 . Other data sources surveyed include: the Lloyd’ s I~eeklv Casualty Reports , the Tanker Casualty Library of Marine Management Systems , Inc ., and the Coast Guard Pollution Incident Reporting System . The nature and char- acteristics of tank vessel casualties that occur in the U.S . offshore waters are described . Systems and techniques considered as alternatives for preventing these c a s u a l t i e s are i d e n t i f i e d , evaluated against each casualty and given an overall rating of casualty prevention effectiveness based on criteria which are defined . The promising systems are selected and conceptual descriptions are presented includ- ing the operational features , technical description , cost , staffing and training required , and legal implementation considerati ons .’ ~~ The report is organized in three volumes: Volume I -. Executive Summary, Volume 11 Technical Analyses , and Volume III -- Appendixes. I?. K~~ Wandi 15. DI.frIbvtI.n St.t..snt Vessel Traffic Management , Tanker , DOCUMENT IS AVAILABLE TO THE U.S. PUBLIC Tank—Barge , Oil Pollution , Oil Imports , THROUGH THE NATIONAL TECHNICAL Vessel Collisions , Groundings , INFORMAT ION SERVICE . SPRINOFIELD. VIR GINIA 22161 Stranding s, Argo Merchant , Oil Spills , Rananings ___________________________________________ 19. ksvrlty CI.s.lf. (.1 his ,...s) I 20. S.CV’Ity CI...IO. (.1 till s p.,.) I 21. N.. siP~~.. 22. P,ics Unclassified I Unclassified 36 P.rm DOT F 1700.7 (5 72) I.p,. ~~~ctI.tt .1 cs..pI.i~d pug. a~thsrli.d L . /c~ ‘I PREFACE The Offshore Vessel Traffic Management (OVTM) Study was per- formed in response to Presidential Initiatives issued in March 1977 which were a result of the Argo Merchant oil spill and several other tanker casualties that occurred in the U .S. offshore waters during the winter of 1976-77. These initiatives called for the Sec re tary , U.S . Depar tment of Transportation, to pe rfo rm sev eral studies and take other actions to prevent or reduce the effects of oil spills from tank vessel casualties in the U.S. offshore waters. The OVTM Study wa s referred to in th~ Presidential Initiatives as “a study of long rang e vessel surveillance and control systems. ” The Transportation Systems Center performed this work in support of the U.S. Coast Guard and the Office of the Secretary of Trans- portation . The study effort was initiated in August 1977 and com- ple ted in June 197 8. This study was directed by the Coast Guard Port Safety and Law Enforcement Division with specific guidance by the following individuals: CAPT Richard A. Bauman , IJSCG; CDR Eu gene J. H ickey , USCG; Mr. Don Ryan , and LCDR John Banna n , USCG . Spec ial recogni- ti on is g iven to the Coas t Guard Pro jec t Manager , Don Ryan , for his many helpful contributions to , and close assoc iati on wit h , the TSC study team . Other contributors were: CAPT (Ret. USCG) Harold Lynch , CAPT Ar thur Knight and CAPT W illiam Mitchell , all of the Bos ton Mar ine Soc iety; J ohn Devanney of th e Ma ssachuse tts Ins titu te of Technolo gy Cen ter for Transpor ta ti on Stud ies; and Patricia Concannon and Jeane tte Coll ier of TSC. NT S nr~ b ‘)fl 0 0 ; CIM. lii - j --— -—- - .- — -~~~ - .-,~~~~~~~- _ _ _ _ _ ~~ I I ( -I I IhIf 1111 iii itiiii I 2 J ~ !~: !;~~~: III) ~ •~~, aj ~~.ii .~~~_ i . .”a’a CS 1$ IS SI II LI SI It .1 CI I II Pt S • j ~ ~ ~~~~~~~~~~~ I U.S ~1i’b~~I .t.. 1 1 2 - - _ _ Y ~ .u I —I ~ I j J fl J L~I .1 1 ~~ :! :~ R!: ! ._ ~~~~!:~~ ~ I — ~I I I ~ h ilt tt~i I1I~iuil ~ if - J I g~~1 ‘ii,Vi iv _ _ _ _ _ 1. INTRODUCTION The purpose of the Offshore Ves sel Traff ic Man agemen t (OVTM ) study is to determine the measures which offer some promise of re- ducing the occurrence of oil tanker and tank-barge casualties in wa ters offshore of th e Unite d Sta tes. The need for improvemen ts in marine safety to prevent oil pollution of the U.S. offshore waters was highl igh ted by a ser ies of tank ves sel ca sual ties in the winter of 1976-77 which included the grounding and total loss of the fully loaded Argo Merchant off the East coast. This rash of tank vessel oil sp ills together with the continuing growth in oil imports to the United States prompted the President to issue several Presidential Initiatives in March 1977 to the Secretaries of the U.S. Departments of Transportation and Commerce to perform stud ies and take actions necessary to prevent them . This study addresses the causes of and alternative measures for prevention of three types of tanker casualties: (a) ground ings (including strandings), (b) collisions between vessels , and Cc) rammings of offshore oil platforms and aids-to-navigation . The vessels of interest include tankers and tank-barges larger than 1,000 gross tons . The geographical area of interest includes the waters from the U.S. coast out to 200 NM around the contiguous 48 states , Puer to Rico , the Vir gin Islands , Hawaii , and Al aska excep t the area north of the Aleutian Islands. Excluded from the study are all ports , harbors , inland waters , and offshore channels that are less than 1 ,000 feet wide. An es tim ated 121 casual ties per tinen t to th is study occurred dur ing the 6-year study period , July 1971 throug h September 1977. Seven ty-ei gh t cases , wh ich were documen ted w ith de tai led ca sual ty investigation reports , were analyzed for causal determination and assessment of system alternatives. 1 0~I - - . - - - , .- --~~ ---~~~~~~~~~- - - — , ---- ~~---- -. —. -- .- ~~~~ -- ~~~~- - . 2. CONCLUSIONS The major conclusions of the study are: o Tank vessel collisions and ground ings that occur in U.S. offshore waters account for approximately nine percent of the total of these types of casualties in all U.S. waters. However , this figure does not reflect the propensity for t’mas sive~ * oil spills in offshore waters. For example , in 1976 , offshore oil spillage reached 40 percent of the total , almost entirely due to the ground in g and subseq uen t breakup of the Argo Merchan t . o The casualty that results in a “massive ” oil spill is very rare; only one, th e Argo Me rchan t , occurred in U.S. offshore wa ters in the six-year study period . Massive spills due to colli- sions , groundings and rammings (of offshore oil production/transfer facilities) have occurred worldwide at the average rate of three per year . However , the potential for massive oil sp ills in U.S. offshore waters does exist , and wi ll likely increase with the pro- jected increases in the volume of tanker traffic and in the sizes of tank ve ssel s. Measur es be ing initiated (e.g., dual radars and LORAN-C equipment requirements) will reduce the potential for casualties resulting in massive oil spillage. o Costs incurred due to oil spills are highly dependent on the locale and environmental conditions as well as type of oil and spill size , and can run to several m ill ion d olla rs per inc id en t . o Groundings probabl y constitute the major threat of pro- duc ing oil spills offshore which may substantially impact the publ ic welfare and environment because these casualties occur close to shore or fishing areas where oil spillage potentially causes the most damage. * “Massive” oil spills are defined herein as those exceeding 1 ,000 ,000 gallons , and “major ” spills are defined as those exceeding 100 ,000 gallons (see Section 5.1).2 o The majority (over 90 percent) of offshore casualties occur w ith in 50 NM of the shore ; the grea tes t d istance fro m shore of any casualty studied is 108 NM. Therefore , there is little justifica- tion for any sys tem to provide surveillance coverage out to 200 NM. o Traffic density is not a factor in the large majority of casual ties. It is rare that a collision involves a third in- dependen t vessel. In 90 percent of the groundings only the ves- sel that grounded is involved in the events leading to the incident. The rammin gs (of oil platforms) have involved only the vessel which rammed the oil platform . o The major causes of groundings are: (1) lack of attention to and misjudgment of the vessel’ s location and movement relative to the water depth , ( 2) lack of vig ilanc e by the crew in usin g all available nav iga tion informa tion , ( 3) inadequa te pilo t board ing procedures for deep draft vessels , (4) lack of knowledge of the presence of subme rged ob jects and shoals , (5) poor navigation! ma neuvering prac tice , and (6) inoperable or malfunctioning naviga- tion equ ipment. o The major causes of collisions are: (1) failure to estab- lish vessel-to-vessel communications and to agree on a plan for passing , (2) poor seamanship , or what may be called a lack of “defensive sailing ,” especially under cond it ion s of poor v is ibil ity , (3) lack of timely assessment of the imminent danger of collision , and (4) poor execu tion of an agreed upon or standard passing ma n euv er. o The major causes of rammings (of offshore oil platforms) are: (1) fa ilure to ma in ta in proper lookou t , (2) poor navigation practice : fa ilure to use all navigation information available on the vessel to determine the vessel’ s position , and ( 3) error in judgment or lack of a tten tion by the conn ing officer in maneuver ing the vessel. o Tugs wi th barges used in the tran spor t of o il represen t an important oil pollution risk. There are many of these vessels carry ing large quan tities (over 100 ,000 gallons) of oil or petro- leum produc ts , with some traveling long distances; e.g., from the Gulf of Mex ico to the northeastern U.S. ports. These vessels 3 I -~~~~~~~~~~~~~~~~~~~~ -~~. - - —~~~ of ten lack ad equa te nav igation equipment and sufficient staffing , certification , and training of the crew for such voyages on the open ocean. Some of the newer barges have capacities as large as 7.5-million gallons and have drafts of 30 feet; despite this , they are exempt from the equ ipment and certification regulations placed on the tankers. o Pilot transfer operations in some areas are inadequate for the need s of tank vessels navigating in bay and port entrances; exampl es are Delaware Bay and Guayanilla Bay, Pue rto R ico. o A navigation aid equivalent to LORAN-C should be required equipment on board seagoing petroleum carrying tank vessels down to 300 gross tons because a vessel of this size can potentially cause a major oil spill. o The results of the study do not justify either a satellite surveillanc e or satellite communications system at this time as a cost-effective alternative for preventing or reducing the risk of oil-polluting casualties in U.S. offshore waters.4 - --~ — ~~~~~ ,... — ~~~~~~~~~ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 3. RECOMMENDATIONS The recommendations resulting from the study are: o Implement a rule requiring all seagoing petroleum carrying vessels over 300 gross tons to be equ ipped with LORAN-C , or an equivalent navigation aid . o Install RACONs on carefully selected buoys or towers to identify positively the entrance to harbors , traffic lanes , and fairways , and other hazardous , frequently traveled offshore areas; example locations are the approaches to Delaware and Chesapeake Bays , and fairway intersections in the Gulf of Mexico. o Perform a study of pilotage practices in Delaware and Guayanilla Bays. Over 40 percent of all groundings analyzed in the study have occurred in these two bays . o Asse ss the costs and benefits of providing LORAN-C cover- age for the Puerto Rico and Virg in Islands area. This aid-to- navigation would likely have prevented one grounding and possibly ‘1 have prevented three others. o Upgrade the requirements for licensing , license renewal , and training of masters and officers of tank vessels to include periodic tests and demonstrations of proficiency (approximately every five years) in the navigation of deep draft vessels , in the use and operation of all navigation aids , and in the knowled ge of regulations and rules of the road . o Implement the “~ essel passport ” system described in Section 7. The costs to the user and the Government are low if existing commun ica tions sys tems are used. Th is is a “core ” system , and is expandable as the need for it develops. In approx imately three years , a study should be made to assess the needs , benefits , and costs of upgrading the capab ility of the “vessel passport” sys tem. o Conduct a design and feasibility demonstration study of a low cos t transponder system . The projected cost of a proposed VHF/transponder system appears to be reasonable , but a design 5 _________________________ J _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - Li stud y is needed to establish more accurately the hardware costs and fe~~~ hility of the system . o Change the equipment , licensing , and pilotage requirements for ocean-going tugs with barges that carry oil , petroleum products , and othe r hazardous subs tances to be compar able wit h thos e f or tank ships. Such vessels should also be required to operate within any off shore vessel traffic management system required of tank ships. o Develop uniform pilotage practices and licensing require- nents for pilots in all U.S. coastal states and territories. o Maintain active involvement in the development of new techniques and systems. The U.S. Coast Guard should initiate more feasibility, des ign , and dem ons tra tion prog ram s of promising system s and techniques in offshore navigation and communications to (1) upgrade continually their capability for reducing the poten- tial for oil-polluting vessel casualties and (2) provide valuable technical inputs into national and international maritime safety programs. o Study the applicability of the “recommended” system alter- natives proposed herein to other Coast Guard mission areas. 6 - -~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -~--. .---- ~~~~~~~~~~~~~~~~~~~~~~~~~~~ 14 , STUDY APPROACH The study approach focuses on analyzing actual casualty reports of tank vessel incidents to determine the causes of ground- ings , collisions , and rammings , and on using this causal informa- tion to develop alternative systems and techniques for their pre- vention. A flow chart of the study tasks is shown below . The primary source of data used in the casualty analysis is the U.S. Coast Guard Merchant Vessel Casualty Report (MV CR) data base covering the period from July 1971 througL September 1977. This data base includes detailed casualty reports from the vessel master and U.S. Coast Guard investigator . Additional data have been obtained from the Lloyd ’s Weekly Casualt ’ Reports. The total number of groundings , col lis ions and rammings that have occ urred in U .S. offshore waters during the 6-year study period is estimated at 12l. * From the detailed casualty records in the MVCR data base , the following 63 tank vessel cases are available for detailed analysis: 47 groundings , 10 collisions , and 6 rammings. However , 15 additional casualties involving non- tank vessels over 5 ,000 gross tons have been used in the analysis of causative factors; i.e., 8 groundings , 7 collisions , and 0 rammings. The total data base for causal anal ysis is 78 incidents. Statistical analysis techniques are not suitable for a data sample of this small size; therefore , each case has been examined in detail for causative factors and assessment of alternative systems. Early in the study, about 30 systems** were identified as holding some potential for reducing casualties. These stems *An exact count of the casualties that have occurred in the U.S. offshore waters out to 200 NM during the study period is impos- sible since the U .S. Coast Guard casualty file does not usually include foreign-flag casualties outside of 3 NM , and Ll oyd ’ s Reports often lack detailed information on casualty location . ** A system is defined as any combination of rules , procedures , equipment hardware /software , and oper atin g pe rsonnel. 7 _ _ _ _ _ ~~~~~~~~~~~~~~ - -~~~~~ - (-J ~~z\ S.c ¼ n v~ — C/) U) z —~ -~~~~ 0~ ” z U) I I— 0 >. ~~~~ ‘- ~~~ Lb z 8 ... - ~~~ . .,. ., ~~~~~~~~~~~~~~ —- -~~~~~ - . -~~-- ---~~~~~~~,-- ~~~~~~~~~~~~~ rang e from simple operating procedures to complex surveillance techniques. From these systems , 34 operational features* are extracted which pinpoint the system elements that are operationally useful in preventing casualties. Each operational feature is evalua ted agains t each casual ty in the da ta base to de termine the most usefu l features. From the results of this assessment , 18 promising systems have been identified , and subjected to a thorough evaluation . They are evaluated not only on their usefu l- ness and effectiveness in preventing casualties , but also on their costs , geographic coverage , operational ease , user acceptance , reliability , state of development , implementabi lity, and Government action required . Evaluating the 18 systems against the data base casualties does not account for the preventive measures which will soon be in effec t , and which will substantially reduce casualties without other systems being implemented . Therefore , a Baseline System has been defined to provide a reference point for the evaluation of the various systems . The effectiveness of other systems is measured by the extent to which casualties will be prevented beyond those prevented by the Baseline Sy stem wh ich h as an effec tiveness of 2 3 percent. The Baseline System includes all currently required equipment , rules , and procedures plus dual radars on board vessels over 10 ,000 gross tons , and LORAN-C , or equivalent navigation equ ipment , on board ves sel s over 1 ,600 gross tons. *An opera tional feature is defined as an element of a system . A system may consist of one or more operational features , som e of which are included in several systems . Also , some opera tional features are independent (they stand alone) , wh ile oth ers ar e dependent on other features to perform their functions. 9 ~~ --- -- --, .——, ., . . ~~~~~~~~~~~~~~~~~~~ -~~-, --- --. , ~~~ - — - . . - ~~~~~~~ .- --,. -~~~~~~~~~ - . - -- --.—- -~~~- -~~~~~~~~~-- ,-—--- 5. FINDINGS The major findings obtained from the casualty analysis can be divided into three groups : (1) the offshore oil spillage problem in general , (2) the characteristics of casualties , and (3) the factors and causes of casualties. 5.1 OFFSHORE OIL SPILLAGE PROBLEM o During the 6-year study period a total of 8 oil spills have resulted from the 63 offshore tank vessel casualties for which detailed casualty descriptions and documentation are available. Five spills are “major ,” exceeding 100 ,000 gallons , and of them , one is “massive ,” exceeding 1 ,000 ,000 gallons. Therefore , the U .S . average rate of major oil sp ills has been 0.83 per year , and the occurrence of a massive sp ill has been 0.17 per year. The oil cargo and o il sp illa ge by casual ty and v essel type s a re g iven below : TANK VESSEL CASUALTY DATA BASE No. Oil Type of No. of of Loaded No. of Oil Cargo Spillage Casualty Inc idents Vessels Spills (K Tons)* (K Tons)* Grounding 47 36 7 1763.0 31.2 Collision 10 6 0 81.3 0.0 Ramming 6 1 1 54.0 2.7 Total 63 43 8 1898.3 33.9 *A ton is approx imately 290 gallons. o Traffic and casualty proj ctions (see Section 6) seem to indicate that the potential for 1 rgcr and more frequent massive oil spills in U.S. offshore waters due to tank vessel casualties will increase. ~ . r - ~~ - - - - ~~~~~~~~ . :~~~~~~~~~~~~~~ T~~~~~~_- - -. -.,- ~ -- ~~~ .-.--. —-. o Worldwide oil spill statistics indicate that an average of 3 to 4 spills greater than 6-million gallons have occurred per year over the 8-year period of 1969 to 1976. o The damage caused by an oil spill varies greatly depending on the type of petroleum , the weather and sea conditions , and the location of the casualty relative to beaches and fishing areas. For exa mp le , studi es perfor med on the Ar go Merchan t sp ill of 7.5- million gallons of crude oil in the middle of the rich Georges Bank fishing area off the Massachusetts coast have found no mea- surable damage to either the fish/marine population or the nearby shore. The wind and wave motion in this instance has pushed the oil spill farther out to sea where it has dispersed . o As indicated in the table above , groundings present a greater threat of oil sp illage in offshore waters than collisions and raminings. Also , groundings usually cause more pollution and environmental damage because a hi gher percentage of them occur near shore (see Section 5.2). 5. 2 CHARACTERISTICS OF CASUALTIES The casualty analysis has resulted in the identification of a number of important characteristics which help provide a general unders tan ding of groundings , collisions , and rammings offshore. o Vessel Size: Tankers involved in casualties in U.S. off- shore waters are usually under 75 ,000 gross tons , and tank-barges generally below 5 ,000 gross tons. o Ve ssel Types: The percen tag e of off sho re tank vesse l collisions involving tankers is about equal to that involving tank- bar ges. On the other hand , tankers are involved in 90 percent of th e da ta base ground ings. o Vessel Flag: All tank-barges listed in the casualty file are of U.S. reg istry , as is expec ted , since the presence of foreign- flag tank-barges is rare in the area under study . Analysis of tanker casual ties in U . S . offshore wa ters repor ted in Lloy d’ s Weekly Casual ty Reports reveals a 1:3 ratio between U.S. and 11 . - ~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -- ---~~~~~~--~~~~~~~~ fore ign-flag vessels. However , a significantly higher proportion (i.e., 1:1) of U.S. tankers appears in the U .S. Coast Guard ’s casualty files because many forei gn-flag casualties beyond 3 NM are not reported since there is no legal requirement to do so. o Dayli ght and Visibility : Darkness and low visibility are important factors in the casualties studied , especially collisions . Overall , 88 percent of the collisions , 69 percent of the groundings , and 67 percent of the rammings have occurred either after sunset or in poor visibility. o Seasonal and Yearly Variations: A study of the seasonal variation of casualties indicates that grounding s are uniformly distributed with a small springtime peak , while collisions peak strongly in the spring and fall , and rammings in the spring . Over the six-year study period , there is a small variation in casualties per year and in casualty type per year. o Locations: Groundings have occurred most often in the Gulf of Mexico , off the U.S. east coast , or the coast of Puerto Rico , with the “hot spots ” being the entrances to Delaware Bay and Guayanilla Bay , Puerto Rico. Over 75 percent of the groundings have occurred within 5 NM from shore , and over 95 percent within 25 NM from shore. A majority of collisions have occurred in the Gulf of Mexico and off the U.S. east coast. Fifty percent of the collisions have occurred within S NM from shore , and 80 percent within 25 NM from shore. All rammings have taken place in the Gulf of Mexico between 12 and 100 NM from shore. (Most U.S. oil platforms are in the Gulf of Mexico.) o Types of Collision Encounters: Fifty percent of colli- sions involve an end-on meeting , 30 percent an overtaking , and 20 percent a crossing . In over 60 percent of the cases , vessels are aware of each other more than 10 minutes before the collision . A third vessel is seldom involved in the events preceding a colli- sion . 12 I ~~~~~-~~~~-. -— ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~ -.~~~~~~~~~~~~~ . _ — - —-- — - - ~1’ 5. 3 FACT ORS AND CAUSES OF CASUALTIES The factors and causes of the 78 casualties subjected to causa tive analys is are summar ized be low. o In general , the causes of the casualties are related to human errors rather than problem s caused by faulty equipment . o In the case of groundings , the mos t common causative fac tor is navigational error (i.e., wrong position) which occurs in 72 percen t of the casualties. In 38 percent of the cases , poor nav iga tion prac tice is involv ed. Other f ac tors are conn ing erro rs (i.e., poor judgment in maneuvering) in 18 percent of the cases; and errors in not waiting for a pilot , or wa iting in an unsafe area , in 13 percent . Some of these grounding s involve more than one of these major factors. o The major factor in collisions is a lack of agreement in th e pas sing maneuver , which occurs in 41 percent of the casualties. Other fac tors are one vessel no t kn ow ing the loca tion of the other (in 24 percent) , and poor performance of standard passing proce- dur es ( in 18 perc ent of the cases) . o The leading causative factor in rammings is failure to ma in ta in proper lookou t on the ves sel , which has been found in 50 percen t of these casualties. Other factors are conning errors (in 33 percen t), and navigational errors (in 17 percent) . 13 I - . —I .— -.--- .—-- .- - — -.- . - - -. -.- ~ --.—.--- .--—---. - . - -- .- — --.- - —------ — .---- ..---- — - 6, CASUALTY PROJECTIONS The casual ties found in the U.S. Coast Guard and Lloyd ’s dat a bases for the six-year study period are a matter of historical re- cord. A casualty scenario for the 1980’s is projected to indicate the expected future severity of the problem and to estimate the effectiveness of the alternative solutions (Section 7) in pre- venting future incidents. The timeframe chosen for projecting casualties is the 10-year period from 1981 through 1990. As a first step , projections of tanker traffic have been developed from a world petroleum network model used by the Massachusetts Institute of Technology .* Three- percent annual growth in the demand for oil in the United States and introduction of deep draft terminal facilities in the Gulf (LOOP) in 1980 are assumed . Using 1977 as the base year , tanker traffic is projected to increase by a factor of 1.13 by 1981 and 2.47 by 1990. In the next step, a gross prediction of future casualties is made by applying the tanker traffic increases to the casualty rates in effect during the study period . It is assumed that (1) groundings will increase linearly with tanker traffic , (2) coll is ions wi ll increa se as the square of merchan t ve ssel tr af f i c , and (3) rammings will increase as the product of merchant vessel traffic and the number of oil platforms .** This step is based on the implicit assumption that the same pattern of causative factors which have prevailed during the l972-l9~ 7 stud y period will continue to occur , and with the same percentage of tank vessel trips resulting in a casualty . Devanney, J ., “Tanker Spills , Coll is ion s and Ground ings ,” MIT , Cambridge , Mas sachuse tts , Under Contract: DOT-TSC-l481 , May 1978. Material on file in the Communication Branch , Transporta- tion Systems Center . **Due to the highly speculative nature of offshore drilling exer- cises , no in crea se in o il pla tform deploy men t i s a ssumed . 14 _ _ _ _ -;- ~ - ~ - ---ã~*~ — Adjustments are then made to account for changes and safety improvements which are expected to he in effect during the future period , independent of techniques presently under evaluation . Specifically, it is assumed that: (1) the Baseline System will he 40 percent in effect by 1980 and 100 percent by 1985 , and (2) the casualties per trip of tankers engaged in Alaskan oil trade will be one-half that of the base period average , due to the superior condition of these vessels , the existence of Vessel Traffic Ser- v ices in Valdez , Puget Sound , and San Francisco , and other inde- pend ent safeguards in effect. After making these adjustments , the number of tank vessel casualties likely to occur in U.S. offshore waters during the 1981-1990 period is projected as follows: 196 groundings , 6S col- lisions , and 10 ramlnings. Of course , the implementation of any independent improvements in marine safety , not foreseen or evaluated in this study, can be expected to reduce these casualty projections to some extent. _ - 7. ALTERNATIVE SOLUTIONS Of the 30 systems considered early in the study , 18 are effective enough to warrant detailed evaluation. Some of these sys tem concep ts have been modified to incorp or ate de sirable operational features. The 18 promising systems are analyzed con- sidering train ing and workload im plications , avai lability of equip- ment , sta te of develo pmen t , vessel and Government costs , U.S. Coast Guard ac tions requi red , and individual estimated effectiveness. Measures in pro gress wh ich are expec ted to be in effec t before 1985 include requirements for LORAN-C , or equivalent navigation gear , on all vessels greater than 1 ,600 gross tons , and dua l radars on all vessels greater than 10 ,000 gross tons. These measures are in- corpo ra ted in to the Basel ine Sys tem wh ich w ill be in ex istence in add ition to each of the other systems being considered. The overall measure of effectiveness used in the study , called ne t effec tiveness , accounts for the simultaneous existence of the Baseline and the sys tem under con sidera tion. I t inco rpora tes ass ump tions conce rn ing the availability of the system , and provides a measure ~f the add itional effec tivenes s of each system beyond th at of the Basel ine System alone . The costs associated with each system are present value cos ts , calcula ted using a 10 percent discount rate. The costs include research and development (R~D), purchase cos ts of equipm en t , and annual opera tion and main tenance (O~M) costs through 1990. The 18 sys tems and their assoc iated effec tiveness and cos t estimates are shown below. The Baseline System alone has an effectiveness of 23 percent. The vessel passport system has the highest effectiveness-to-cost ratio of the active * sys tems. The other active systems achieve higher effectiveness , bu t at an in- crease in cost. The passive * systems either call for Government action or require on-board vessel equipment . Voluntary purchases of on-board equ ipment and additional measures taken by the U.S. Coast Guard , such as tig h ter licens ing stand ards , can be expec ted to reduce future casualties beyond any active system implemented. *“Active ” sys tems require U.S. Coas t Guard par tic ipa ti on in the ir day- to-day operations , while ~passive~ sys tems do no t . 16 Ii ~ . —- .. — ~~~~~~ —------. —,-- .-- —~~-~~~~—--. — - s--: - ~~~: ~~~~~~~~~ ---- - ------ - 1.- ic >-~ U) 0 r-.~ ‘.1) ~~ ‘-I) c-.~ ~ ~~ LI) t— t— ~~ — r . o~ iJ~ C C) U) -~ c~ ~~ C) C~ ‘C c— ~~ U) ‘C -~~- U) r— C) ‘C C 0 .— — LI) ~-4 ~~ — ~~ — ‘C .~~u— 1) r-4 C.) ~~ F- S c.. 0 ‘— F- , . ) o ~-‘ J~ C C) C) C) 0 o ~~ c-I LI) c-I LI) c-I LI) LI) U) ,~~ C) .~ L C) C) L/) ~ ~C ~~ — c ~~ C. ~~ e-~ ~~ -~ _) — C’) c-~ ~‘) u C. 0 0c ~~z i. ~.. 1— 2 ’-- 0 U) ..r 4.~ s —~ .C C.) F-~ U ) i c b~ U) ~~~ . ~~ CC. F- Cl) ? 00 U) 00 1-- c-I ~~ . ~~ I— C) LI) ~~ U) F- F— C . . .... C... U) — C. C. C 00 C. C ,‘) r— C. C. C. C. LI) ‘C C’) U) c-- 00 ‘C C 0 .-) — C’4 r~) ‘—I ~~~ — (‘ .1 ~C ~ C Z <U~~) c-i — F-~ — C) C/) 0 2 C ~~ F- 2 O _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ C. < U) ~~ CC. C 0 1- .C C >-. ~~ ic E-. 4.) -— ~~ _ U );~ -~~ < L~~U)~~ -~ C) C S ~~~~~~~ C. ‘C C. C— C. r— U) .0 LI) ~~ - 00 ~‘) cC LI) U) ‘0 C’) C’) C... S Z C.~) ~~ ~C ~~ Li) ‘C .-~ —4 ‘-I 0 ~ = F—~ .-~~ .C >.~ U) ~~ F-C. C. .:C. C) _ _ _ _ _ _ _ _ _______________________________________________________________ C C) 0 C Cd U 45 C . 0 0 1 1 ) 45 C Cl. C) 4.’ 45 C) ‘-4 C C U 0) Cd U ’— ~ 0 0 ~- C C C . . - ~- ~ C 4.’ ~- CC. E ~~~~G) C C ) 4.) 4-e ‘~j ~~ C)~~~ ~.. $... U ) Q G ) — Cd C u~~-l ~.. C CO C C ) ~~~~~~~--4 0) Cd U ) C C Cd ~~~~~ C - i I.. 00 C O ~~~~~~~~~~~~~~~~ U) U) ~- CO .-4 ~~ .,-4 4.1 < ~~ ~~. C) C ~.. C C C . —’ CO ~~~~~~ C) C/) ~~~~~ U) 4-’ 0 < E 0 0~ .. C ) > C ) 5 ~~~~Cl) 4.J ~~. C) C) C s - U ) . C. 4-’ C) ~~. U) 4) 0 0 ) C ~. ~~~~~~~ F— 4.’ C C) 4-’ 00 I C) C - — ~ 0 0 0 Cd C 0CC U) C C ) ~- 0 ~~ U ) -~’ C u 0 0 C C) 4.J < C - ~l 0. C O O 04) >.. ~~~~~~~ 05 F 4 .,.~~~~~ 4 - 1 C E ~~ ...~ U) I- ~~~C C/) — C 0. C- — C 4-4 ‘ 4.’ 0. 00 .C C - ’ C- F— C - U ) t ., C) Ci U) C) C) U) 0 U) C C) . 4-t If) 0~~~~ -‘-~ 4.’ C G ) C ~~~~~~~~~ U) 4.’ U) 4.’ ~~ 4.) CC. C C . O~~~-’ ~ ~.. CO e C L . 4-’ C C d 0 . C C C ~< C D CL. C CO C- C - - - - ~ C~~~C C) U 0 < CO C C-. 0 0 L~~~0 . < ~~~~~~~~~ U ) F - F - < 0 .u ) Z C U ) U ~~~~>~~~-E- 4.1 4.J 4J , . 4 z z — ’-- 4 5 4 1 45 — —‘ c-i C’) ~~ L/) ~O C-- 00 0) C. ‘—4 c-I C’) ~~ U) ‘C C-. 45 ic , 4 — ~4 — — — — — — 45 17 - ~ .- . - -— - - - - -~~~ - ~~~- ~~~~~~~~~- - ‘~~~~-- ---- . ~~~~--~~~~~~-— — - ~~~------‘- - --. -. . — ~ , —- ----- ,,- - . . - ~~~ - ~~~ ,.-- .- ~~~~ -- _ _ _ _ _ _ ~‘.l SYST LM DE SCRIPTIONS The fol~~ wing paragraphs briefly describe the 18 systems , and their chief capabilities and limitations. 1. Baseline System -- The Baseline System is the reference against which other systems are assessed. This system includes all current equipment , rules , and procedures plus LORAN-C , or an equivalent navigation system , on all vessels over 1 ,600 gross tons , and dual radar systems on all vessels over 10 ,000 gross tons. It is assumed that the Baseline System will be fully implemented by 1985. Uowever , it does not include LORAN-C coverage of Puerto Rico and the Virgin Islands area because there are no present plans for this addition. The Baseline System is assumed to be operating simultaneously with all other systems discussed below . lA. Extended Baseline System - - The Extended Baseline System includes the expansion of LORAN-C coverage to the Puerto Rico and Virgin Islands area plus all of the Baseline System . 2. Vessel Passport System - - A vessel passport system is the simplest form of an active system; i.e., one involv ing shore-based personnel. This system is highly oriented toward reducing accidents , especially groundings and rammings , by restricting the movements of substandard ve ssels: i.e., by not allowing ves els bound for U.S. ports and with unacceptable histories into territorial waters; by placing conditions on the entry into (or departure from) ports for vessels lacking proper certification , proper charts , or hav ing equipment defects or outages; by issuing help ful advisories on wea ther , cur rents , and spec ial cond it ions; and by coo rd ina tin g pilot transfer procedures. The opera tion of th e sys tem centers aro und two checkpo in ts (refer to figure below) : vessels bound for U.S. ports are required to check into the system at about 24 hours prior to entrance into internal wa ter s (w ith in a toleranc e of abou t 6 hours , earlier or later) , and again at ano ther poin t approx ima tely 1 hour prior to entry . At the first checkpoint , permission to enter port is granted 18 . . CC CO?’Th1 NET CENTRA L FACILITY - ~~~~~ S1~OR(. CUECKPO INT - PIL OT COORD I NAT iON c~oss-c~flj CK INSTRU MENTS TRAFFIC \ ~~~~~~~~~~~~~~~~~~~~~ VIlE ~~ HF CI% OR SATE LLITE \~ FIR ST ~~ CHECKPO INT ‘~J (Z 4 HR ) -PER~4I SSI ON TO ENTER -WEATHER VESSEL PASSPORT SYSTEM 19 — - - - -- —-- . ---- - ~~- — - - . - . .— -- - -—~~~~~-- - ~~~~~~~ -- — - ~~~~~~~- . .--— ~~~~~~~--. ~~~ --.- _ _ - _ or dcnied ,* and any special conditions are placed on entry at that time , At the second checkpoint , special bulletins concerning weather , buoy outages , and other tanker traffic are issued to the ve .;sel , the vessel master is provided a benchmark to calibrate his navigation gear , and any necessary p ilot coordination is set up. The hardware and software necessary to implement the system are largely in existence today . Communications at the 24-hour checkpoint is accomplished by present long distance communications gear , while a designated VHF radiotelep hone channel is used at the one-hour checkpoint. No other on-board equipment is required. Access by the U.S. Coast Guard to a data base on tankers and tank-barges operating in U.S. waters is required. This exists in large measure in the U.S.C .G. Marine Safety Information System (MSIS) , which is presently being implemented. The vessel passport system also requires a network cf about 40 RACONs to be placed near the location of each second checkpoint , and at other locations along the coast and at fairway intersections. Some collision avoidance service can be provided by modif ying the vessel passport system to provide advisories regarding tanker traffic to all vessels in the area . The chief advantage of the vessel passport system is that it provides the U.S. Coast Guard with the means to make a jud gment , in a timely manner , on the danger that a vessel presents to the U.S. coast. The chief probleri in its operation is the possibility of linguistic communication d~ fficu1ties at the second checkpoint. The communication requirement at the first checkpoint circumvent s this difficulty by allowing teletyped or telegraphed data. 3. Automatic Monitoring System - - The automatic monitoring system includes the vessel passport system plus the capability of providing vessels with traffic information , collision alerts , and *It is antici pated that 80 to 90 percent of the arriving tank vessels will be granted unconditional entry , and that this will approach 95 percent as vessel owners and officers become familiar with the system . The total time spent by a vessel’ s crew in meet- ing the requirements of the system on a routine voyage is expected to be less than 15 minutes - - a very minimal burden. 20 _ _ _ -- - -—.---- - ~~~~~— ~~~~~ —-.----“ - ~~~~--. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .. - - ~ - .“--- . - .-_ - .. - , — .- — - ~~ --.. ~~ - . - . grounding alerts. A data/voice communications set , which interfaces with the electronic navigation instruments , gyro compass , and ship ’s log, is required on board all commercial vessels. The commun i- cations set provides the shore station with automatic updates of position , course , and speed. No action is required of the vessel master other than turning on the equipment. The shore station keeps track of all vessels , and plots courses and projected positions using data/voice communications equipment , computers , and computer driven displays. 4. Direction Finding (DF) Surveillance System - - Rather than being a separate system , DF surveillance is a capability which can be added to the passport or automatic monitoring systems. It utilizes two DF stations at each port to determine the position of vessels operating w ithin 20 NM of the port . When the VHF trans- mitter on board a vessel is turned on , two bearings are established by the DF stations which the shore operator can plot to determine position. (This procedure can be automated.) This system has the advantage of providing an inexpensive way of checking a vessel’ s position from shore . It is somewhat limited in range and accuracy. 5. Radar Surveillance - - Radar provides the shore operator with a plan-position-indicator (PPI) display of vessels , buoys , and terrain features within the range of the radar , with a re- fresh rate of about once every four seconds. It requires no equip- ment on board the vessel , but does not provide identification of targets. * Due to its cost and limited range (20-40 NM), i t is not a viable candidate to provide wide surveillance coverage , and is considered only as a backup to a vessel passport system near ports that have special needs justif ying its use. 6. Satellite Surveillance -- Satellite systems offer high accuracy and nearly global coverage. In a typical system , a shore station sends an interr~ -.igation signal , selc ctively addressed and including a time identifier , to a master satellite , wh ich *fjowever , i~~~ ompatib le transponders become required equipment in the fu ture , they can provide vessel identification . 21 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ retransmits it to the selected vessel. Equipment on board the vessel rec ogniz es and dec odes the s ignal , adds vessel identifica- tion , ves sel data , and time code , and retransmits the signal back to the shore station through the master plus one additional sa tell ite. The shore station computer then uses the measurements of time differences in the transmitted and received signals over the two different paths , together with the known satellite locations , to determine the vessel’ s posi tion. Position information at the shore station is of little use without reliable communication with the vessel. To take full advan tage of the w ide covera ge of the sys tem , equivalent communica- tions coverage is required , such as via satellite using the same rece iver terminals. Satellite systems hold promise of high effec- tiveness , but at a cost that may be prohibitively high. 7. Intensive and Periodic Training -- As a “system ,” training involves specific courses in the use of navigation instruments , rules of the road , proper navigation and helm procedures , and strict licensing requirements. The specific form of the training, and the critical judgments involved in developing training requirements mus t be perf ormed by exper ienced marine rs. S imulators off er a chance to experience “dangerous” conditions without the risk of acc ident , and can be an effective training aid. The major problem with training recommendations is that they require international agreement to be effective. Recent developments have been en- courag ing however. 8. Expanded Traffic Separation Schemes - - Traffic separation schemes are currently in use at several major ports , and are ef- H fective in collision prevention .* Wh ile the casualty analysis does no t ind ica te the need to es tabl ish more of them , there are three areas where improve men ts can be made: in fa irw ays , adj acent to channels and traff ic lanes , and in narrow passageways where alterna te routes are available. Wh ile such improvements are not costly, they are hampered by the need for coordination with the U.S. Army Corps *In the six-year study period , there have been no end-on collisions and only one cross ing collis ion i traff ic lanes. 22 .0I r . . . ‘- ~~~~~~~~~~~~ - -—— — ~~~~~~~~~~~~~~ .- ~~~~~~~~~~~~~~~~~~~~~~ . ~1~ of Eng ineers and adoption by IMCO. 9. Improved Aids-To-Navigation - - The present system of aids- to-navigation , maintained by the U.S. Coast Guard , is probably the most comprehensive of its kind in the world. Specific areas for improvement have been identified in the study, notably in buoy identification , buoy location and monitoring , and the need for more RACON5. Such improvements will benefit the prudent mariner , but without measures to ensure their use , cannot by themselves guarantee a reduction in casualties. 10. Pilot Transfer Procedure System - - The present procedures by which a pilot is contac ted and a tim e and loca tion arr anged fo r pilot boarding has serious shortcomings in a few areas. The system of rul es and proc edu res needs to be str engthened , at least for tank vessels , to limit their entry to specified safety zones until a pilot has boarded . The main problem is that each port has unique ocean bottom topographies , and unique traditions , making it difficult to formulate National standards. In addition , most such pilotage requirements are established under state , rather than Federal , author ity. 11. I~pproved Equipment Standards -- A system that incorporates improved equipmen t standards ess enti ally adop ts the prac ti ces of a pruden t vessel owner , and tr ies to enforce them on all v essels bo und for or departing from a U.S. port. These practices include : purchase of equ ipmen t mee tin g a recogn ized standard , maintaining a comprehensive spare-par ts supply, preventive maintenance , and one member of the crew capable of making at least simple repairs. The firs t two meas ures ca n be read ily es tablished by occasional inspec tions. The third and fourth are easily avoided by any vessel owner trying to cut costs. 12. Processor-Aided Nav igation Alert System - - With improve- men ts in perform ance , cos t , and rel iability of microprocessors and other dig ital circu itry, it is now poss ible to au toma te and integrate several br idge func ti ons rel iably and rela tively inex- pens ively. For example , dev iation from pres elec ted tracks can be 23 4 ~~~~~~~~~~~~~ . _ _ _ _ _ _ _ _ _ _ _ _ continuousi displ ayed , cross-checking can take place between independent navi gational instruments (e.g., Omega and LORAN-C) and an indication provided if the differences are excessive , set and drift can be calculated and displayed , and traffic lanes and even depth sounder readings can he superimposed on radar displays. Alarms can be desi gned to sound if the vessel is off course. Capabilities like these will he available at reasonable costs within the next few years. The chief concern is that capabilit ies will become widel y used before the subtleties of use have been adequately assessed , and appropriate equipment standards determined . 13. Depth Alert -- Depth sounders are standard equipment on ves sel s of all s izes , are highly reliable from the point of view of availability, and they are simple to use. It is feasible to attach an alarm feature to a depth sounder , wh ich w il so und if the measured depth becomes less than a preset critical value. Without proper interpretation however , false alarms can become a nuisance. False alarms can be caused by a school of fish or even a single f ish as well as by engine noise and electrical disturbances. Proper signal processing techniques must be developed and proven before this system can be used with confidence. If such techn iques are dev eloped , depth alert devices will probably be ava ilable at a low cost. 14. Scanning Sounder - - The scanning sounder is a device which allows an area on the ocean floor forward and abeam of the vessel to be mapped out . Ideally, a dev ice such as this provides depth information out to about 0.5 - 1 NM ahead , and 1 ,000 or so feet to each side . It can be coupled with an alarm to incorporate the capabilities of the depth alert. This display is typically similar to a rada r scope , but is somewhat more complicated in its inter- pretation . At present , such sounder s are li mit ed in use pr imar ily to research and military applications , al though some are used to loca te f ish. Scann ing sounders mee ting the above requ ireme nts can be very effective in avoiding shoals and thus reducing ground- ings , bu t they are l imi ted in usefulne ss by their hi gh cost , complexi ty of in terpre ta tio n and use , and need for develop men t in the area of signal processing . 24 I __ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ .— . _ _ _ - -. - - 15. Collision Avoidance Aid -- Collision avoidance aids are presently available commercially. They process radar data , identif y targets , track vessels and other targets , pro jec t fu tur e vessel courses on a display , and prov ide a warn in g in case of a predic ted collision . Automa tic acquisition of targets is crucial to their effec tiveness in offshore waters ; however , no t all coll is ion avo idance aids have this capability . They are quite effective , but are slow to adjust to frequent maneuvers of other vessels . The ir expense l im its them to use on lar ge ves sels. Th is reduces their availability, and thus reduces their net effectiveness as a general countermeasure to collisions. 16. Radar Perimeter Detection Device_- - The radar per ime ter detection device is an adjunct to a standard on-board radar , and is designed to be a low-cost , limited capability , collis ion avoidance aid. It is based on the concept of guard zones , or circles with own vessel at the center. If a radar target appears within a guard zone , an alar m sounds , alerting the vessel watch- stander to the presence of an echo . A particularly useful design incorporates outer and inner guard zones , each inde penden tly def ined and adjustable by the operator. It does not track targets or p roject courses , but merely alerts the bridge of a nearby target. I t is qui te inex pens ive , but requires the watchstander to interpret and assess the situation manually. It is also susceptible to saturation and false alarms by clutter and land echoes. 17. VHF/Transponder System - - The VHF/transponder system is an anti-collision concept developed at TSC to provide an inexpensive a’.ternative to the interrogator/transponder system described below. It consists of a simple VHF code transmitter/receiver and an assoc iated radar transponder. It provides the vessel watchstander wi th an aler t and iden tifica tion infor mation when anothe r equipped vessel approaches within a few miles. The watchstander can ascertain the corresp ondin g radar targe t by manually in terroga tin g the identified vessel. The system facilitates bridge-to-bridge commun i- ca ti ons by providing vessel identi fica tion , and can be confi gured 25 —— ~ -.- __ ~~~~~~~~~~~~~~~~~ to provide the intended maneuver of the vessel as well. Thus , its chief advantage is in providin g these services inexpensively, mak- ing it widely available. The chief difficulty is that it requires FCC and IMCO approval to transmit even the simple codes at VHF . 18. Interrogator/Transponder System - - An interrogator/ transponder system provides a clutter-free radar-type display of all vessels in the area which are transponder-equipped , com plete with identifying codes which can be displayed and used to help establish verbal radiotelephone contact . It also allows the vessel watchstander to select a target , and interrogate the vessel to ask its intended maneuvers. The U.S. Maritime Administration has developed such a system , called MRIT (Marine Radar Interrogator- Transponder). The system works similarly to a radar. When the operator wishes to obtain information on a vessel , the all-call mode (CQ) is selected. The interrogator transmitter on board own vessel then sends a coded pulse stream which causes any transponder- equ ipped vessel in th e area to reply w ith its own pulsed da ta stream , including vessel identification. The replies also paint a bright echo on the radarscope , superimposed on the normal radar echo . Other vessel data such as course , speed , s iz e of vessel , draft , etc., can also be obtained if the interrogator transmits the proper code. The chief advantages of the system are the clutter-free fea ture , the target identification , and the bridge-to-bridge communica ti on capability, all of which are useful in avoiding coll is ions. Unfor tunately, its higher cost precludes its ins tallation on smaller vessels , so tha t it only prov ides pro tec tion against the larger vessels which can afford to install similar equipment . 7.2 SYSTEM STRATEGIES Descr ibing the sys tems ind iv idually and citing their cos ts and effectiveness estimates do not highlight the tradeoff in costs be tween vessel owners and the Gov ern m en t ; nor do they con si d er the effect of requiring several on-board instruments or various com- bina tions of systems. To accomplish these objectives and provide 26 tI ~~~~~~~ . ~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ —~ --- .- — -- - —. . , _ _ _ _ _ _ _ a clearer pi cture of the relative m erits of Government versus vvs .~cl o~ ner expenditures , seven strategies are postulated . The pare~1th et ic a l numbers refer to the systems described above . A . ~o Further Action - - This is the Baseline System (1). B. H igh Vessel/Low Government Investment - - This strategy requires Navigation Alerts (12) and VHF/Transponders (17) on al v essels over 1 ,600 gross tons , Radar Perimeter Detection (16) and Depth Alerts (13) on all tank vessels , and Colli si on Av oida nce A ids (15) and Scan ning Dep th Sounders (14) on all tankers greater than 10 ,000 gross tons. C. Modera te Vessel/Low Government Investment - - This strategy requ ires Nav igati on Ale rt s (12) and VHF/T ransponders ( 17) on all vess els greater then 1 ,600 gross tons . D. No Vessel/Moderate Government Investment -- This strategy consists of the implementation of the Vessel Passport sy stem (2). E. No Vessel/H igh Government Investment - - This strategy consists of the implementation of Radar Surveillance (5) (without on-board transponders), in addition to the Ve ss el Pa sspor t sys tem (2) F. Low Ves sel/High Government Investment - - This strategy consists of the implementation of Automatic Monitoring (3) G. High Vessel/High Government Investment -- This strategy consists of the implementation of Satellite Surveillance (6) The figure below shows the costs (present value) and total casualties prevented for the seven stategies through 1990 , and take s into account the time requ ired for implementation. I t is apparent from this figure tha t even with large expendi ture s in vessel equipmen t , the total effec tiveness of low Governmen t cost strategies (B and C) is less than that of the vessel passport system (D). The figure also shows that for other strategies , 27 ~~~~~~~~~~~~~~~~ -~~~~~~~~~~ _ ~----- ,. -. -— — —,~~~ --_-—-- _ -. -- --. ..-~~—--_--. -.. --- ,, . - - h. — LU - 1 I— 0 — . Z o LU E 0 > — 0 o LU I. 0 0 9 . 0 U — .~~0 5, If) (I) _ _ _ _ _ _ _ C . s ..~~ i~ I ~~~ ~~~~~~~ LU -_ .c 5, .— > ~ — ~~ >.~~~ .~~ >~ — — .. ~ OL. LU 05) I- 0. .0 5, .0~~~~ > ~~ .~~~0 0 ~ C o .- F-. — ~~~~~ — 0 .0 5, 0 I.) ~ ~~~4) 5, — ~~ .,. . -~ U — 5 ,0~~~O < > 5 , 5 , C. LU 0. 5 , > 0 0. I ii.. 0.5, ., 0 5, 15 15 — . .— 41 I . ~— .~~ ~~ — I . — 5).~..0 .l j .— ~~~~ 15> , 15 > 14 15 .0 15 ~~U U 15 F- 15~~~~~ 5, — Z O r l _ 1 55 , Cl) — .00> ‘.-. LU .).~~ 5, 0 * 0 0 . C..0 Cl) 1/1 0.... < 0 ~ : ~- 0 F- 14 (sl15ttop 30 suotItiw ) (~n1vA iNElS~Ilid) i.soa lYLO! 28 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ . -. .—~~~~- _ ~ .——.p., --- .- - - ~~~—.—--— .-- --------- ~•- — .- ~~~~~~~~~~~~~~~~~~~~~~~~ increased effec tive ness beyond that of the vessel passport system is achieved at progressively higher costs. The vessel passpor t sys tem emer ges as the clea r cho ice of the various system des igns considered. The au toma tic mon itoring sys tem (F) , which includes the ve ssel passpor t sys tem , achieves a signifi- cant increase in effectiveness , bu t with a reduced effectiveness-to- cost ratio. It can be phased into the vessel passport system at a later date if experience justifies this action . Adoption of ei ther of these sys tems can be expec ted to reduce subs tantially coll is ions , rammings , and groundings in the offshore waters of the United States. This reduction can be further enhanced by the seve ral independe nt programs of ac tion recommended in Sec tion 3. *U.S. GOVtN NNENT PRINTING OPPICt ~ * 147S—700-40$ / %75 850 copies 2 9/30 I ., — _ _ ,- ~~~~~~~-. .— - - ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~1 •1