investigation into the sinking of the ro-ro passenger ... · msc/ circ. 574 & circ. 649 for one...

Investigation into the Sinking of the

Ro-Ro Passenger Ferry EXPRESS SAMINA

Prof. Apostolos Papanikolaou, NTUA-SDL National Technical University of Athens

Ship Design Laboratory (NTUA-SDL) GREECE Email: [email protected] , URL: http://www.naval.ntua.gr/sdl

Reference: A. Papanikolaou, D. Spanos, E. Boulougouris, E. Eliopoulou, A. Alissafaki, “Investigation into the Sinking of the Ro-Ro Passenger Ferry EXPRESS SAMINA” ,

8th International Conference on the Stability of Ships and Ocean Vehicles ,STAB 2003, Madrid, Spain, September 15-19, 2003.

Safety and Energy Efficient Marine Operations

19th November 2015

Presentation Outline

The accident

Investigation set up

Investigation analysis

Conclusions and recommendations

19-Nov-2015 “Investigation into the Sinking of the Ro-Ro Passenger Ferry EXPRESS SAMINA” - Prof. Apostolos Papanikolaou, NTUA-SDL 2

The Passenger/Ro-Ro Ferry EXPRESS SAMINA

132 4 5 6 7 8 9 10 11 12

132 4 5 6 7 8 9 10 11 12

SHIP PARTICULARS Ship Name EXPRESS SAMINA Ship Type Passenger / Car Ferry Builders CHANTIERS DE L'

ATLANTIQUE - St. NAZAIRE

Date of Built 01/01/1966 Area of Operation AEGEAN SEA Type of Trip Day / Night Length over all, [m] 115 Breadth moulded, [m] 18.1 Depth to the upper deck, [m] 10.7 Depth to the main deck, [m] 6.01 Subdivision Draught, [m] 4.55 Service Speed, [kn] 18.0 Gross Register Tonnes 4407 Deadweight, in tonnes 1089 Passengers according to summer certificate

1038

Passengers according to winter certificate

335

Number of persons in Boats 674 Number of crew 62

Compliance with the provisions of EUROSOLAS regulatory framework, disposing an A/Amax over 0.98, according to MSC/ Circ. 574 & Circ. 649 for one compartment standard .

3 19-Nov-2015 “Investigation into the Sinking of the Ro-Ro Passenger Ferry EXPRESS SAMINA” - Prof. Apostolos Papanikolaou, NTUA-SDL

The Passenger/Ro-Ro Ferry EXPRESS SAMINA


The Accident

Accident time: Tuesday September 26, 2000, 22:10 local time

The ship: passenger/Ro-Ro ferry EXPRESS SAMINA

Trip conditions: Average speed of 18.5 knots and moderate weather conditions of 5-6 Bf

People onboard: 533 people onboard, 472 passengers and 61 crewmembers

Cargo payload: 17 trucks and 34 cars on car deck

Approaching the port of the Greek island Paros, she collides with the rocky islet Portes , at a distance 3 nm from the destination port

The ship sank after abt. half an hour as the result of flooding of the main engine room and further progressive flooding of the entire buoyant spaces

The accident caused the loss of 80 people


The Accident


The Damage Openings

Damage ‘A’ : due to stabilizer fin penetration, abt. 3,00 m long

Damage ‘B’ : set of three openings (raking cracks) with the longest one 0,60 m

Damage ‘C’ : raking damage above WL, more than 6,00m long

Damage ‘D’ : cracks of secondary importance


The Main Damage Opening at E.R.

The crucial underwater damage ‘A’ due to the penetration of the right

stabilizer fin into the main engine room (one compartment damage)


Flooding Scenario Accident’s events reconstruction was based on the systematic analysis and

matching between the information obtained from survivors’ testimonies

and divers’ findings, the performed hydrostatic calculations and finally the

numerical time domain simulation of ship’s foundering.

In this way, the most probable scenario was identified as the scenario that matched best the information and facts in hand and also satisfied the conditions resulting from the numerical tools simulation.

Divers Findings

Testimonies

Hydrostatic Calculation Simulation

Flooding Scenario


Testimonies Analysis

One hundred and ninety two (192) testimonies of surviving passengers and seventy-five (75) testimonies of crew (from whom twenty-nine (29) testified more than once) were captured in a developed database and systematically analyzed.


Testimonies Analysis – Time of Collision and Foundering

Time of Accident & Time of Sinking

22:0422:0722:1022:1322:1622:1922:2222:2422:2722:3022:3322:3622:3922:4222:4522:4822:5022:5322:5622:5923:0223:05

1 6 11 16 21 26 31 36 41 46 51 56 61 66 71 76 81 86 91 96 101 106 111 116 121 126 131 136 141 146 151 156 161 166 171 176

Passengers

Time of Hitting the Rock

Time of Sinking Average Time of Accident = 22:10 (Sample 92 passengers)

Average Time of Sinking= 22:42 (Sample 43 passengers)


Testimonies Analysis – Access to Life Jackets

Τρόπος Παραλαβής Σωσιβίου

Με Ιδία

Πρωτοβουλία

66%

Πλήρωμα

7%

Άλλος επιβάτης

23%

Δεν έλαβε

σωσίβιο

4%

Δείγμα 221 Επιβαινόντων

How passengers got life jackets

From other passenger

28 %

Never got

2 %

On his own

62 %

From crew

8 % Sample of 181 passengers


The Hydrostatic Damage Stability Analysis 3 Possible Damage Scenarios

the ship proved satisfactory in terms of reserve buoyancy and relevant stability criteria to withstand the particular (as other) one compartment flooding.

it proved that for the particular loading

condition that the ship could survive this two compartment damage as well.

For the indicated 3 compartment

damage, the bulkhead deck line immerses at the equilibrium position, however the ship would have adequate reserve buoyancy and stability as well as adequate margin of heel to avoid an immersion of the damage opening located at platform deck. She would float at least for a prolonged time to allow safe evacuation.


The Watertight Doors

The found most probable scenario considers 9 out of 10 watertight doors open. This scenario is practically also confirmed by the testimonies and divers findings.


NTUA-SDL Simulation Method

Investigation analysis employed the

CAPSIM time domain numerical simulation code of NTUA-SDL for the damaged ship motion and flooding simulation.

In particular it was possible

To simulate the flooding process of the damaged compartments and the subsequent progressive flooding

and

To estimate the sequence of a series of characteristic events that took place during the ship’s sinking and are of importance for the legal process.


NTUA-SDL Simulation Method

CAPSIM Code 3D non-linear time domain code for the 6 DOF ship motion at zero speed of intact or damaged ship in regular and irregular seaways, considering variable flooded water (inflow-outflow hydraulic model)

Computing time at ALPHA WS 1:4 (to real simulation)

RAM requirement < 10 Mb

• Simulation method calculates the nonlinear 6 DOF motion of an (intact or) damaged ship in time domain under the excitation of external forces (gravity, sea waves, wind etc) and of internal interaction effects due to floodwater.

• Ship to wave hydrodynamic interaction is treated within linear potential theory (panel code NEWDRIFT).

• Ship to floodwater interaction is treated by a simplified formulation of the coupling forces.

Damaged Ship

excitation motion X(t) Y(t)

f(X(t),Y(t),t)=0

CAPSIM +

NEWDRIFT

Ship Particulars Environmental

Parameters

NEWDRIFT Code

Seakeeping code based on 3D panel method (pulsating source) - 6 DOF

Linear and quasi-nonlinear frequency domain analysis (drift force effects included)

Regular waves excitation – irregular seaways through spectral analysis procedure

Intact vessel


Geometric Modeling Damage openings, Doors, Staircases, Ventilation openings, etc.

are geometrically modeled permitting the simulation of water flow through them.

Spacious objects, like main engines and generators, were modeled as 3D geometric spaces.


The Estimated Heeling Scenario

Comments on characteristic stages of ship’s sinking

0

5

10

15

20

25

30

35

40

0 200 400 600 800 1000 1200 1400 1600Time [sec]

Hee

ling

[d

eg]

Immersion of Damage 'C'

Shift of Cargo

Immersion of Promenade

Deck

Immersion of Embarkation Deck

Collision

Max Transient Heeling

3.3 6.7 10.0 13.3 16.7 20.0 23.3 Time [min]0.0

Collision

Transient Heeling

Immersion of damage ‘C’

Immersion of Promenade Deck

Immersion of Embarkation Deck

Shift of Cargo


Progressive Flooding of Spaces

Water pours into the main engine room through damage opening A and flows through the open left watertight doors into the entire ship.

Through the numerical simulation, the time series of water elevation in every compartment is obtained, enabling the estimation of the time during which the particular compartment was accessible or not by people onboard.

-4,0

-3,5

-3,0

-2,5

-2,0

-1,5

-1,0

-0,5

0,0

0 200 400 600 800 1000 1200 1400 1600Time [sec]

Flo

od

wat

er F

ree

Su

rfac

eb

elo

w S

till

Wat

er P

lan

e [m

]

Main E.R.

Aux Fwd E.R.

3.3 6.7 10.0 13.3 16.7 20.0 23.3 Time [min]0.0


Sea Waves Effects Prevailing weather conditions during the ship’s sinking were moderate up

to 6 Bf with a significant wave height 1.5-2.0 m

Numerical simulation proved that wave effects have limited effect on the events evolution with the main effect arising at the later stages of flooding

0

5

10

15

20

25

30

35

40

0 200 400 600 800 1000 1200 1400 1600Time [sec]

Hee

ling

[d

eg]

3.3 6.7 10.0 13.3 16.7 20.0 23.3 Time [min]0.0

Heeling in SeawayHs = 2.0 mTp = 5.7

Heeling in Still Water


Sea Waves Effects

Evolution of free surface of floodwater inside the E.R.

-4,0

-3,5

-3,0

-2,5

-2,0

-1,5

-1,0

-0,5

0,0

0 200 400 600 800 1000 1200 1400 1600Time [sec]

Flo

od

wat

er F

ree

Su

rfac

e in

to E

.R.

bel

ow

Sti

ll W

ater

Pla

ne

[m]

Seaway

Still Water

3.3 6.7 10.0 13.3 16.7 20.0 23.3 Time [min]0.0


Alternative Scenarios Alternative scenarios considering watertight doors closed were

also investigated and proved that ship would have survived in these cases or would have behaved in different way.

0

5

10

15

20

25

30

35

40

0 200 400 600 800 1000 1200 1400 1600Time [sec]

Hee

ling

[d

eg]

3.3 6.7 10.0 13.3 16.7 20.0 23.3 Time [min]0.0

Scenario of three compartments flooded

Heeling in Still Water


Ship Drift The ship wreck was found 1.4 nm away from the collision spot,

just 0.3 nm away from the island’s coastline.


Conclusions

The passenger/Ro-Ro ferry EXPRESS SAMINA sank after collision with a rocky islet due to the lack of watertight subdivision resulting from the fact that the water tight doors were left open. – Ship watertight subdivision should be recorded and be controllable at any

time

The employment of a time domain simulation method in the investigation of the ship’s loss proved particularly useful, enabling the reconstruction of history and the estimation of the events’ sequence independently of the quality of available testimonies of survivors.

Ship evacuation studies, considering the time of a ship to sink, should exploit modern analysis tools to rationalize and improve the evacuation procedures, minimizing the risk of loss of lives. An increased research effort in this field appears advisable. – Time to sink and stability during the flooding process are two significant

parameters that need further investigation


The Sinking Scenario

The collision on the rocks at 22:10 (+0 min)



The transient heeling of 5 deg at 22:13 (+3 min)



Immersion of upper damage opening at 22:23 (+13 min)



Immersion of promenade deck, heeling 23 deg, at 22:27 (+17 min)



Immersion of embarkation deck, heeling 33 deg, at 22:30 (+20 min)


THANK YOU VERY MUCH FOR YOUR KIND ATTENTION Prof. Apostolos Papanikolaou, NTUA-SDL

National Technical University of Athens Ship Design Laboratory (NTUA-SDL) GREECE

Email: [email protected] , URL: http://www.naval.ntua.gr/sdl

investigation into the sinking of the ro-ro passenger ... · msc/ circ. 574 & circ. 649 for one...

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