International Journal
on Marine Navigation
and Safety of Sea Transportation
Volume 6
Number 2
June 2012
187
1 SUMMARY OF THE ACCIDENT
On the 23rd September 2008, the M/V OCEAN
ASIA with engine-trouble is towed through the Ha
Nam canal into the port of Haiphong at the speed of
3 knots. At buoy No. 21, the pilot of M/V OCEAN
ASIA saw three vessels intended to overtake him so
he required the other three vessels stop these actions
because of narrow area. But they are continued over-
taking M/V Ocean Asia. First one, a tanker overtak-
en M/V Ocean Asia at buoy No. 21; then M/V Far
East Cheer had overtaken M/V Ocean Asia on the
portside. The last one, M/V SITC Qingdao proceed-
ed to overtake M/V Ocean Asia.
Figure 1. The scene of the accident
At this moment, M/V Ocean Asia was in the cen-
ter line of the canal. The M/V SITC Qingdao sailed
at the speed of 12.7knots. When the distance be-
tween two vessels is 0.5 NM, M/V SITC Qingdao
reduced her speed and her speed is 9 knots when she
was passing M/V Ocean Asia. The distance between
side to side of the vessels is 10 – 15m when they
were passing.
At the moment, when the stern of the M/V SITC
Qingdao had passed the bow of M/V Ocean Asia,
the M/V Ocean Asia quickly crashed into the shore,
stranded on the right bank of the canal.
The particulars of these vessels are as follow:
- M/V Ocean Asia:
o Call sign: 3EMN4
o Flag: Panama
o IMO number: 7712353
o L.O.A: 158.85 m
o Breadth: 23 m
o Air draft: 41.8 m
o Draft F/M/A: 6.3 m /6.4 m /6.6 m
o GT 10835
o DWT: 13992 MT
o Cargo: 345 containers equal 5738 MT
- M/V SITC Qingdao:
o Call sign: V2BO3
An Analysis the Accident Between M/V Ocean
Asia and M/V SITC Qingdao in Hanam Canal
(Haiphong Port)
V. NGUYEN CONG
Vietnam Maritime University
ABSTRACT: The paper presents a special case of the ships accident. The accident was happened without any
contact between ships. The cause of the accident is the hydrodynamic interaction between ship in a shallow
canal and the analysis is consulted to determine the percent of fault of the accident.
188
o Flag: Antigua & Barbuda
o IMO number: 9207560
o L.O.A: 144.83 m
o Breadth: 22.4 m
o Air draft: 41.5 m
o Draft F/A: 7.0 m /7.2 m
o GT 9413
o DWT: 12649 MT
o Cargo: 5900 MT
The canal’s depth and breadth are 8 m and 80 m
respectively. It is one way canal and taking over is
prohibited here. The M/V Ocean Asia was towed by
three tugboats: M/V Da Tuong towed at the bow by
towing line 150 m in length; M/V Transvina and
M/V Marina 18 supported at the stern (Fig. 1). At
the moment of the accident, there was not current in
the canal; water is still.
In this accident, there was no contacting between
vessels so there was no evidence on the hulls. To
blame on M/V SITC Qingdao, it is necessary to im-
prove that the M/V Ocean Asia came aground due to
the influence by overtaking of M/V SITC Qingdao.
2 RESEARCH BY SCALED MODELS
To research by scaled models, it is necessary to have
condition of the experiment as same as real situation.
The formula of the relation between a real vessel
speeds and a scaled model vessel is as follows:
kVV
vesselrealelmod
×=
(1)
where, k is the dimensional ratio of real vessel and
model.
In 2003, a research about “Hydrodynamic Interac-
tion between Moving and Stationary Ship in a Shal-
low Canal” were carried out by Stefan Kyulevche-
liev, Svetlozar Georgiev, Ship and Industrial
Hydrodynamics Department, Bulgarian Ship Hydro-
dynamics Centre, Varna, Bulgaria and Ivan Ivanov
Shipbuilding Department, Technical University of
Varna, Bulgaria. They use two scaled models with
the parameters are show in the Table 1.
Table 1. Parameter of the models
__________________________________________________
Moving hull Stationary hull
__________________________________________________
Length between perpendiculars [m] 4.000 4.400
Length at waterline [m] 3.881 4.400
Beam [m] 0.456 0.456
Draft [m] 0.080 0.080
Block coefficient 0.928 0.870
Displacement [m
3
] 0.131 0.139
__________________________________________________
The experimental set-up with the accepted coor-
dinate system for the forces and moments are shown
schematically in Figure 3 below. The relative posi-
tion of the two models has been determined by de-
tecting a marker at the bow of the moving model
with a laser fitted at the stationary model.
a) Moving hull
b) Stationary hull
Figure 2. The models were used in the experiments
Both the models have been free to sink and trim,
but fixed in all other degrees of freedom. The mov-
ing model has run along the centerline of the tank
with a width of 2.6 m.
Figure 3. Experimental set-up
The measuring unit, mounted on the stationary
hull, has comprised two strain gauges for the longi-
tudinal force, allowing in this way deduction of the
yawing moment, and one strain gauge for the lateral
force. Two lasers detecting the distance to fixed hor-
izontal plane attached to the canal wall have meas-
ured the sinkage of the hull.
Experiment was carried out with the sets of canal
depth, model speed, and distance between two ves-
sels when overtaking others (Stefan 2001). In this
189
paper, the results of experiments which have condi-
tions similar to conditions of the accident of the M/V
Qingdao and M/V Ocean Asia will be presented.
The Figure 4 and Figure 5 show the experimental
results when the moving model was overtaking sta-
tionary model at the speed of 0.875 m/s and ratio of
canal depth and draft (H/T), respectively, 1.5, 2 and
2.5.
The length between perpendiculars of SITC
Qingdao LBP is 134m. The length of the moving
model in experiment is 4m. So the speed of 9 knots
of the M/V SITC Qingdao equivalent to the model
speed as follows (Cohen 1983):
)s/m(800.0)knots(56.1
134
4
9V
elmod
==×=
(2)
The speed of moving model in the experiment
was 0.875m/s, so it can be considered as same as the
speed of SITC Qingdao when she was overtaking
M/V Ocean Asia.
About the depth of the canal, the rate of draft and
depth of both vessels draft SITC Qingdao and Ocean
Asia were only about H/T = 1.1 ÷ 1.14. From Figure
3 to Figure 5, forces and torque acts on the station-
ery are depended in inversely proportional to the
value of H/T. This leads to the amplitude of forces,
moment acts on the M/V Ocean Asia will be greater
than the value represented on a graph of the case
H/T = 1.5.
Figure 4. Hydrodynamic load CX at equal speed and different
water depths
On the Figure 4, when the distance from SITC
Qingdao to the Ocean Asia was about two lengths of
a vessel (x/l=-1.5) the M/V Ocean Asia was pushed
a bit forward. Since bow SITC Qingdao access to
the stern of M/V Ocean Asia (x/l = -1), the M/V
Ocean Asia was pulled back until the stern of M/V
SITC Quingdao is passed the bow of M/V Ocean
Asia (x/l = 1). During this period, the force got the
maximum value as the bow of M/V SITC Qingdao
passing the bow of M/V Ocean Asia.
The transverse force acting on the hull M/V
Ocean Asia was variable as follows: When the dis-
tance of two vessels is half of vessel’s length (x/l = -
0.5, Fig. 5), the M/V Ocean Asia was pushed toward
the shore. Then, from x/l=0 to x/l=1, M/V Ocean
Asia was pulled to M/V SITC Quingdao. This pull-
ing force was maximum value at the position A on
the Figure 5.
Figure 5. Hydrodynamic load CY at equal speed and different
water depths
At the moment, when the stern of M/V Quingdao
passing the bow of M/V Ocean Asia (x/l=1), the
transverse force was change the direction quickly
and the M/V Ocean Asia was pushed strongly to the
shore.
The Figure 6 shows the moment effects on the
hull of M/V Ocean Asia. Before x/l=0, the moment
changed the direction frequently. It courses the
swaying to the M/V Ocean Asia. When the bow of
SITC Qingdao was passing the bow of Ocean Asia,
the moment rises quickly (point B in Fig. 6). It turns
the bow of Ocean Asia strongly toward to the right
canal.
Figure 6. Hydrodynamic load CN at equal speed and different
water depths
The transverse force and moment acting on the
M/V Ocean Asia peaked almost at the same time as
the bow of SITC Qingdao passing the bow of Ocean
Asia (points A and B in Figure 5 and Figure 6). Un-
der the influence of pulling force and moment, the
M/V Ocean Asia changed her course toward the
right bank of the canal.