628
5 Determination of the reduction in the level of
navigation safety as a result of the proposed
changes in the form of exemption from the
obligatorypilotage.
6 Analysis of the economic effectiveness of the
proposedsolutions.
3 IMPACTOFPILOTAGEONNAVIGATION
SAFETY
3.1 Definitionofaccident riskreduction
In the most of studies on the subject under
consideration, the so‐called factor of reducing the
numberofaccidentsduetothe presenceofthepilot
onboardisused.Thesemaybepercentagevalues(as
usedinthisstudy)orfractionalvaluesintheformof
riskreduction
(Rp),e.g.Rp=1/3,whichmeansthatthe
presenceof apilot reduces around 67% of accidents
[LentzandKroon,2010].
n
bp=np/(1‐Rp)
where:
n
bp–numberofaccidentswithoutpilotonboard;
|n
p–numberofaccidentswithpilotonboard;
R
p–percentageriskreductionduetopilotage.
Available sources concerning the impact of
maritime pilotage on the safety of navigation were
analysed.Themainproblemincollectingdataonthis
problem is the fact that there are few areas in the
world where sailing with and without pilots is
allowed.The
literaturereviewindicatesthefollowing
areas where such data has been collected and
analysed:
1 the Danish Straits, including the Great (between
2004‐2012),theLittleBeltandtheSound(between
1982‐1994).
2 TheGreatBarrierReefarea inAustralia,including
theStraitofTorres(between1985‐2003).
3
BosporusStrait(between1982‐2003).
4 TokyoBay,1970sresearch.
Navigation accidents are divided into types. The
study covers only three most important of them‐
occurringmainlyinpilotedareas,thatis:
1 grounding,
2 collision,
3 impactonthefixedobjects.
Available literature sources determine risk
reduction as a result
of maritime pilotage
provocation.Ingeneral,thesourcesareconsistentand
statethat:
1 the pilot on board contributes more to reducing
theriskofstrandingthantheriskofcollision;
2 thereductionofshoalentryisintherangeof50%
to80%,
3 collision reduction averages between
25% and
60%.
3.2 Cond itionsoftheŚwinoujście‐Szczecinwaterway in
termsofpilotage
TheŚwinoujście‐Szczecin waterway has special
navigational conditions, which differ from those
mentioned in Chapter 3 of the area where pilot
studieswereconductedontheimpactofpilotageon
navigationsafety.Theseinclude,among
others:
1 very small width of the waterway, the ratio of
which to the width of ships is 3 to 5 times the
width of the ship, which requires considerable
skills in maneuvering in limited areas, including
passingtechniques,
2 high complexity of the track and navigational
signage, which requires
a high level of
navigationalknowledge,
3 lackofthenavigationassistanceserviceprovided
by VTS resulting mainly from the design of the
route(thisserviceisnotpossiblewiththecurrent
stateofthetechnology),
4 highinteractionwithothervesseltrafficregarding
passingandovertakingrestrictions,
5 complexityof
portregulationscoveringabout100
pages,
6 the complexity of the port structure and
infrastructureintheformofturningplace,basins,
etc., which makes it difficult to determine
manoeuvring tactics or interactions with other
participantsandberths.
As a follow‐up step, the average values of the
coefficient of
reduction in the number of accidents
(basedonOzsoysalR.&OzsoysalA.O.(2006),Lentz
A.& Kroon I. B. (2010),White M. (2000))caused by
pilotage were determined for pa rticular types of
accidentsandarepresentedinTable1.
Table1.Averagepercentagevaluesoftheimpactofpilotage
onthesafetyofnavigation,asadoptedinthestudy
_______________________________________________
Typeof Averagereductionof Relativeaccident
accident accidentriskasaresultreductionexpressed
ofpilotageRp%[%]asRp
_______________________________________________
Grounding 600.60
Collision 550.55
Impact820.82
Average650.65
_______________________________________________
4 TRAFFICONTHEŚWINOUJŚCIE‐SZCZECIN
WATERWAY
Vessel traffic is the most important accident factor.
Vesseltrafficin2003‐2016wasanalysedonthebasis
of data from the Central Statistical Office [Statistical
Yearbooks of Maritime Economy 2010‐2017] and the
Maritime Office in Szczecin. It shows a slight
variation of several percent without a clear upward
trend(Tab.2.).
Thewaterwayisdominatedbysmallunitswithan
overalllengthofupto90m.Figure1 onthebasisof
MaritimeOffice data for 2017(3162 entries ofships)
showsthepercentageshareofvesselsinsizegroups
in intervals of 5m. It can be noted that the vessels
currentlyexcludedfrompilotage,i.e.withalengthof
lessthan60m,areabout250vessels(8%ofthetraffic).
Unitsfrom60mto75mare300units,whichis10%of
thetotaltraffic,andunitsfrom75mto
90mareabout
250 units (8% of the traffic). 1580 units per year is
approx.50%ofallshipstrafficinSzczecin.