水先人が同乗する3,000トンのコンテナ船がヌメアを出発し、礁を抜けてハバナ航路に向かう途中、狭いウッディン海峡を通過した。狭水路の中でもさらに狭い部分に差し掛かったとき、暗闇に接近してくるヨットのライトがスピンネーカの向こうで光る様子が目に入った。

　ヨットの方位ははじめ左舷船首で2ポイントであったが、針路に沿ってこちらの船首に異常接近した。ヨットは全長約50フィートほどで高価な印象だった。安全に横切り、今度は我々の右側に来たヨットのライトが突然赤に変わった。ヨットは進行方向を変え、またこちらに向かってきた。あまりにも接近しすぎたので、衝突になるかというところであった。我々はいっぱいに舵を切ったが、ヨットは船首の下に消え、マストの上の部分だけが見えていた。私は恐る恐る衝突音が聞こえるのを待っていた。ヨットは無事に通過したが、ヨットの船長の報告によると5メートル以下で危うく衝突を免れたということであった（ちょうど5メートルほど突き出していたバルバスバウは見えていなかったようだ）。

　水先人はVHFでヨットにフランス語で抗議した。船からは憤慨に満ちた様子で、「講習は受けており、左舷対左舷で航過すべきだったことはわかっている。自分が右舷側にいたので、船首を横切って反対の左舷側にいかなければならなかったのだ」という応えが返ってきた。

　ブリッジチームと水先人との協力と連絡に関する例をもうひとつ挙げる。この報告（99-261）は、ワシントン州環境局（PO Box 47600, Olympia, WA 98504-7600 USA）がまとめた。

　

　1998年9月5日18時30分ごろ、MONCHESGORSK号がワシントン州アンダーソン島のアムステルダム湾に差し掛かったところで、アンダーパワーで座礁した。事故は白昼、晴天の下で発生した。同乗の水先人は、ワシントンのオリンピアからドレイトン航路とバルチ航路を抜けてアンダーソン島の回りを北に船を導く予定であった。この座礁による石油の流出はなく、船は翌朝タグボートが引き揚げた。

　

　MONCHEGORSK号座礁の推定原因としては、確認なしで右舷側に旋回したため、ドレイトン航路において船が不適切な位置で航行していたことが考えられる。水先人の話では、近くを通り過ぎた小型船舶の進路を避けることを気にして、旋回しようとしたということだ。その後船の停止や左への旋回など操船を試みたが間に合わず、座礁を避けることができなかった。座礁の要因として以下の点が挙げられる。

　

　この報告では安全上の問題として、以下の重要性を指摘している。

　

　エラー連鎖という概念と連鎖が起こるサインは、キャプテンA・J・スウィフトのBridge Team Management: A practical guideで紹介されている。1998年9月5日に発生したMONCHEGORSK号の座礁事故では、ここで指摘される指標の多くが観察されていた。

　船長と一等航海士は、出発前に航路についての話合いをしなかったため、ブリッジチームはこの点につき、何も彼らから得ることができなかった。一等航海士は服務規程に背き、予定ルートからの逸脱をすぐに船長に知らせなかったため、ブリッジチームはこの点につき、彼らから何も得ることができなかった。そういった手落ちと、船がドレイトン航路に差し掛かったときに一等航海士と水先人が十分な意思疎通を行わなかったことがブリッジチームの状況把握を損ない、結果的にエラーの連鎖を断ち切ることができなくなった。

　

　

Seafarers International

Research Centre

Cardiff University, UK

　

 This article follows on from an earlier one I wrote (published in Seaways August 2002) which looked at overtaking near miss encounters (NME). Here I will take the opportunity to present the results of an analysis of crossing vessel NMEs (near-miss encounters) that occurred in the Dover Strait. It was found that there were 66 crossing encounters that resulted in a NME and of these only six were within three cables or less. This contrasted with the overtaking situation where there were 68 NMEs and of these 28 were within three cables or less. It is argued that this smaller number of close NMEs resulted from the crossing vessel taking action regardless of its status in relation to the Colregs (Statutory Instrument SI 1996/75).

　

 As outlined in the August article, the traffic separation scheme (TSS) in the Dover Strait works exceptionally well in de-conflicted opposing flows of traffic which transit the area. An example of this is the way that the number of collisions in the Dover area fell from 142 for the period 1956-1965 to 37 for the period 1971-1980 (Cockcroft, 1982) after a TSS was set up in the late 1970s. Similarly, the Turkish Straits witnessed a dramatic drop with the introduction in 1994 of a TSS where the incidence of collisions fell from 155 for the period 1990-1993 to 11 for the period 1995-1998 (Cockcroft, 1998). However, crossing and overtaking situations remain to be resolved by the officer of the watch (OOW). The Dover Strait is an extremely busy area for all forms of traffic and this is especially true for crossing vessels, due to the high number of ferries that operate there. Furthermore, it has been reported that 48 per cent of all collisions result from crossing situations (Cockcroft, 1982). Therefore, although at the time of writing there has not been a serious collision involving a crossing situation resulting in loss of life, the possible consequences of such an event warrants research into this situation.

 It should be noted that collisions, although very important, are rare events. There are approximately 400 ships passing through the Dover Strait every day and yet there are only approximately four collisions a year, a ratio of one collision per 36,500 vessel transits. Consequently, it has been shown that it is important to research near misses, or near accidents, as it is very difficult to learn lessons from accidents due to their complexity and rarity (Tamuz, 1987). Therefore, the research presented here will concentrate on the analysis of NMEs within the Dover Strait in order to ascertain the reality of collision avoidance within this area.

　

 The same criterion for the definition of a NME is used in this article as in the earlier one, namely the violation of a circular space eight cables in diameter. This definition was derived from a review of literature on ship domains (Fujii and Tanaka, 1971, Goodwin, 1977, Coldwell, 1983, Zhao, et al., 1993). The distance that was chosen has generated a certain level of discourse relating to minimum or safe passing distances and risk of collision. However, in this case it is not being used to define what is or is not a safe or minimum distance at which ships should pass. In this research I have used the distance of eight cables simply as a unit of analysis.

　

　

 The same 24-hour period was selected for this research as for the overtaking study and so the same, reasonably good, weather conditions were present, as was the unexceptional nature of this day. Restricted visibility and any extraordinary events are of limited interest, for it is normal events which lead to normal accidents (Perrow, 1999). The day in question remains unspecified to ensure the anonymity of all those seafarers working in the area at the time.

　

　

　

 Data were obtained from the radar records held by the Channel Navigation and Information Service (CNIS), which were released by the MCA. CNIS hold data relating to the tracks of all the 400 vessels that pass through the Dover Strait every day. In order to gain a quantity of data that could be analysed, an area stretching from the CS4 buoy in the north, to the Varne Bank in the south and from the separation zone in the east, to the port of Dover in the west, was selected for this study. This area encompassed all the ship to ship interactions for the vessels using the south west traffic lane of the TSS, as well as those crossing it.

 The data from CNIS took the form of radar tracks printed on A2 sheets, which were then scanned and saved on computer (Figure 1).

 With the use of image manipulation software, the radar track plot was cleaned so as to isolate each individual vessel track and then each track was compared with each other (Figure 2).

 Figure 2 shows the tracks of two vessels passing 10 cables from each other, at 14:08, during a crossing situation. This illustrates that, through the utilisation of rigorous analysis, clear and reliable data has been produced in relation to vessel Interactions within the Dover Strait.

　

 It was found that there were 66 crossing situations that resulted in a NME; the full data is shown in Figure 3.

 It is very interesting to note that ships passed within three cables of each other on only six occasions out of 66 NMEs. In contrast, Figure 4 shows the 68 NMEs that resulted from overtaking situations.

 The overtaking situations resulted in 28 out of 68 NMEs where the passing distance was three cables or less. Furthermore, when the two sets of data are compared, the median passing distances for crossing and overtaking situations are six and four respectively. Therefore, there is a greater margin of safety in place for crossing situations when compared with overtaking situations.

 In order to ascertain the deviation from the general track, a cross-sectional distribution chart was created (Figure 5). To produce this chart, a line A〜B, was constructed along the traffic lane and the distance between the vessel's track and the Varne light buoy (marked 'VAR') was measured. This distance was then plotted on a chart to produce the distance distribution chart shown in Figure 6.

 As can be seen, the 12 tracks for those vessels that did not encounter any near crossing traffic show very little deviation in their route across the Strait. The median distance from the Varne light buoy was 35.5 cables with a standard deviation of 1.3.

 This process was then repeated for the 35 vessels, which had an unclear passage and their tracks are shown in Figure 7.

 A second cross-sectional distributional chart was drawn for the unclear crossings and is shown Figure 8.

 The differences between the clear and unclear crossings ate quite striking. The vessels crossing the traffic lane and encountering traffic within it took considerably different routes from those that had a clear crossing. The median distance from the Varne light buoy was very similar to that of the clear crossings with a figure of 35.6 cables, however, the standard deviation was very different at 6.0 cables.

　

　

 From this illustration of the vessels' tracks, it is apparent that there is clear variation in the routes chosen by the OOW's on the ships crossing the TSS. Where the vessel is crossing, and there is no near encounter with another vessel, the OOW will take a standard route, plus or minus 2.5 cables. However, when the OOW is onboard a ship that does have a near encounter with another ship, then very different tracks are taken. Rather than sticking within a narrow corridor five cables wide, the ship with an unclear crossing takes a route plus or minus 18 cables of the median line.

 The conclusion to be drawn from this variance between clear and unclear crossing routes is that the vessels that should be maintaining their course and speeds are not. Rule 15 is not being applied as required by the rules, as vessels preparing to cross the TSS are taking early action to keep out of the way of vessels crossing from their own port side. This is a clear violation of a very simple rule and so shows how rules in practice are operationalised in such a way as to be most advantageous to the person applying them. This finding can be further explained within the context of sociological studies of rule use.

　

　

 Sociologists study the methods that people use to construct and manage their lives and working environment in order to gain an understanding of people, and the society in which they exist, as they perceive it. From a number of well-related sociological studies, it has been seen that the traditional view of rules, 'as external factors governing, even determining, the behaviour of those subject to the rules' (Harper and Hughes, 1993) has been overturned and in its place is a belief that rules are both contingent and defeasible (Bloor et al, 2001) among other sources. This is to say, no matter how exhaustively a rule is written, it is always contingent in such a way that it is dependent on or conditioned by something else and it is always 'defeasible', that is, it is capable of being annulled or made void. Therefore, in practice it has been found that people do not follow prescriptive rules bureaucratically, but rather use their own experience and stock of knowledge to adapt the rules to their own perception of the reality of the situation. Furthermore, many operators see this rule-bending as a feature of both their own knowledge and experience (Keating, 2001) and are able to account for their actions as being within the rules so as to demonstrate their competence within an organisation.

 In the same way, the collision avoidance procedures that seafarers utilise are elaborations, albeit reasonably stable ones, of the Colregs and this phenomena has been shown to be a feature of non-rule following behaviour, especially in routine activities (Bloor, 1980). This phenomenon of a stable elaboration has been illustrated in this study.

 The OOWs on the ferries will keep clear of the traffic that is following the TSS, rather than complying with Rule 15 rigidly. A reasonable explanation for this is that the OOW on the ships crossing the TSS do not want to have their actions constrained by the rules because they do not trust the OOW on the give-way vessel actually to keep clear and so take unilateral action to keep out of the way. In this way, the OOW on the crossing traffic will make a very early assessment of the traffic situation within the TSS lane and then adopt a route across the TSS in such a way that the ship does not have a near encounter with any other and so have to rely upon the other taking action. This explanation would then account for the deviations within the tracks of the crossing vessels. Therefore, the sociological view that rules cannot be simply imposed and then followed, as they are always open to variable interpretations, is found to exist in crossing situations in the Dover Strait.

　

　

 The reality of collision avoidance within the Dover Strait can be characterised by stand-on vessels acting as give-way vessels and give-way vessels not taking any action, as they no longer need to. These actions have evolved over the years to become the sociologically described stable elaborations of the rules. This custom of keeping clear of traffic following the TSS appears to be a very practical solution to the problem of ensuring collision avoidance. In fact, in today's world where everyone is required to minimise losses in a proactive manner, the practice of standing-on and so bringing a potential collision closer before taking any action, could be viewed as rather a quaint, outdated tradition.

　

 I wish to acknowledge the contributions of Captain J Garner of the MCA for giving permission for the release of the data held CNIS, Mr E Musson and Mr C Mulvana of the MCA for their assistance in the retrieval of the traffic data at Dover coastguard station and Mr G Hood climate enquiry officer of the Meteorological Office for the provision of the meteorological information.

　

　

 Belcher, P, 2002. 'Overtaking in the Dover Strait, an analysis of near miss encounters', Seaways, (7) pp 13-16.

 Bloor, M, Kavechi, E, Sampson, H and Thomas, M, 2001. 'Worse things happen at sea'; Paper presented at the Work Employment and Society Conference, University of Nottingham.

 Cockcroft, AN, 1982. 'The circumstances of sea collision', Journal of Navigation (35) pp 100-112.

 Cockcroft, AN, 1998. 'Safety of navigation in the Turkish Straits' Seaways, (5) pp15-16.

 Coldwell, TG, 1983. 'Marine traffic behaviour in restricted waters', Journal of Navigation, (36) pp430-437.

 Fujii, Y and Tanaka, K, 1971 'Traffic capacity', Journal of Navigation, (24) pp 543-556.

 Goodwin, EM, 1977. 'Determination of ship domain size', In: Proceedings of the Conference on Mathematical Aspects of Marine Traffic, Hollingdale, SH (Ed) Academic Press, London pp 103-128.

 Harper, RHR and Hughes, JA, 1993. 'What a f-ing system! Send 'em all to the same place and then expect us to stop 'em hitting', Making technology work in air traffic control', Technology in Working Order, studies of work, interaction and technology, Button, G, (Ed.), Routledge: London.

 Keating, M, 2001. 'Risky Business: the role of culture in accident causation and the structural pressures which may encourage it', Work Employment and Society Conference, University of Nottingham.

　

　

 Perrow, C, 1999. Normal Accident: living with high-risk technologies (Second Edition), Princeton University Press, Princeton.

 Statutory Instrument SI 1996/75 Merchant Shipping Safety, The Merchant Shipping (Distress Signals and Prevention of Collisions) Regulations, HMSO, London. Tamuz, M (1987). 'The impact of computer surveillance on air safety reporting.' Columbia Journal of World Business, (22), pp 69-77.

 Zhao, J, Wu, Z and Wang, F, 1993. 'Comments on ship domains', Journal of Navigation (46) pp 422-435

　

　

（当大學における調査は、日本船主協会欧州地区事務局長赤塚宏一氏のご紹介による。）

　

　Southampton大学は、元は理工科の短期大学であったのが近年格上げされて大学となったもので、今のところUniversity-style Instituteと見なされているため、今年は提携（Franchise）する大學から学位が授与されるが、来年以降は本大學独自の学位が授与されることになっている。

　職員は、教授を含めて1,300人が在職しており、生徒は毎年13,000人が入学しているという。

　学部（Faculty）は、Media、Arts and SocietyとBusiness、Law and Management及びTechnologyの三つがあり、また、Technologyには、Digital Communications and ComputingとDesign and Architecture及びMaritime and Coastal Studiesの三つのSchoolがある。

　一方、School of Maritime and Coastal Studies（MCS）には、二つのCentreがあって、その一つは、1932年に創設され、1946年に現在地のWarsashに移転されたWarsash Maritime Centre（WMC）である。

　ここでは、航海、機関、船橋当直、荷役、消火、ARPA等のシミュレイションはもちろんのこと、海技免許に係わるSTCW条約に沿った教育、訓練がLong Courseで行われているとともに、部員等の特殊な分野の生徒に対してはシミュレイションを使った訓練がShort Courseで行われていて、毎年9,000人の卒業生があるという。

　他の一つのCentreは、Maritime Research Centre（下記）であり、各種の調査、研究を行っている。

　

　同校において、Human Factor或いはSafety Cultureを調査している研究者と意見の交換を行った。

　Dr. Michael L. Barnettは、かっては商船の船員で、現在はSchool of Maritime and Coastal Studiesに所属するMaritime Research Centre（MRC）のHeadとして活躍されているが、Warsash Maritime Centre（WMC）のシミュレイションを活用した訓練等から派生してくる問題を学問的に研究する傍ら、外部から委託された研究（Externally Sponsored Research Project）も行っている。