Sailed4seas的部落格

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The collision took place around 120 nautical miles East of Ningbo.

May 11:  The 4,650 TEU Safmarine Meru was sailing from Qingdao to Ningbo, China with less than 400 full containers on board when the incident occurred. SAFMARINE MERU fire, as of morning May 11, seems to be if not extinguished, at least under control, with some 40 containers either destroyed, or damaged. Vessel doesn’t have power, there was small leak, most probably in engine room area and probably, in a stern hold next to superstructure. Maersk said, that the vessel is seaworthy enough for a towage.

The 8,814 TEU Northern Jasper was built in 2009 and is owned by Norddeutsche Reederei. Vessel, according to AIS, after being anchored for some time off Zhoushan, on May 11 resumed her sailing to initial port of destination, Yangshan, so hopefully, damages aren’t serious. 

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Gross Tonnage: 50686,  Deadweight: 50415 t,   Length Overall x Breadth Extreme: 292m × 33m

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Gross Tonnage: 94407,  Nosivost: 108804 t,  Length Overall x Breadth Extreme: 333.58m × 43.32m

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Situation Awareness

1. Time 16:29:51 (10 minutes before TOC Time of Collision)

• Speed vector are three minutes which are used as indicated.
• South Bound S/B vessel "SAF" course 192 degrees / speed 19.4 Kts.
• North Bound N/B vessel NORTH course 003 degrees / speed 11.9 Kts. 
• If Both vessels maintained her course and speed, North Bound vessel will pass South Bound vessel astern (No collision risk at all)

2. Time 16:31:51 (8 minutes before TOC Time of Collision)

Situation Unchanged.

3. Time 16:32:51 (7 minutes before TOC Time of Collision)

Situation Unchanged. S/B vessel altered course to Port Side 5 degrees.

4. Time 16:33:51 (6 minutes before TOC Time of Collision)

S/B vessel altered course to Port Side 13 degrees (from 190 degrees), but still inside the safety limit.

Situation Unchanged. Two vessels course line had no cross point, i.e. no collision point. Two ship distances is 6 Nautical Miles. Both ships should keep course for safety or Alter Course to Starboard side to increase safety margin.

5. Time 16:34:51 (5 minutes before TOC Time of Collision)

S/B vessel altered course to Port Side 13 degrees (from 190 degrees), but still inside the safety limit.

N/B vessel altered course to Port Side 4 degrees (from 359 degrees),

Two vessels course line had no cross point, i.e. no collision point. Two ship distances is 5.0 Nautical Miles. Both ships should keep course for safety or Alter Course to Starboard side to increase safety margin.

6. Time 16:35:21 (4.5 minutes before TOC) Collision Risk involved.

S/B vessel altered course to Port side 4 degree (from 177 degrees, 30 seconds before).

DTC Distance to collision is 4.5 min x Speed 11.4 Kn = 0.855 NM = 1583.5 Mtrs

Possible Maneuvering Distance for 1583.5 Mtrs = 4.75 Ship’s Length (1583.5 / 333.6 Mtrs)

N/B vessel altered course to Port Side 7 degrees (from 359 degrees, 30 seconds before),

DTC Distance to collision is 4.5 min x Speed 19.1 Kn = 1.433 NM = 2653 Mtrs

Possible Maneuvering Distance for 2653 Mtrs = 9.1 Ship’s Length (2653 / 292 Mtrs)

• Two vessels course line are end to end (head on exactly).
• Two ship distances is 4.5 Nautical Miles.
• Collision Risk involved here.
• Against common sense, high speed vessel actually has more maneuvering space than slower vessel.(in this example, almost Double own ship’s length for maneuvering purpose. 9.1 Vs 4.75)
• High Speed vessel covered wider Possible Area of Collision. (1.433 Vs 0.855 NM ahead)
• Possible Area of Collision is proportional to Own ship’s speed. (1.433 Vs 0.855 NM=> 4.5 min x Speed 19.1 Kn Vs 4.5 min x Speed 11.4 Kn  = 19.1 Vs 11.4 )
• You want higher speed, you get more trouble. This is Ironic Rule. No matter how much vessels are out there. Once your speed reduced to Zero, the collision risk reduced to Zero too.
• Collision Point expanded to Possible Area of Collision. Diameters is 667 Meters ( 2 ship’s length of N/B vessel)
• S/B vessel needs to alter course to Starboard side 11.5 degrees to clear Possible area of collision,
  • α =  Sin-1 (333 M/ 1667 M) = 11.50

7. Time 16:35:51 (4.0 minutes before TOC Time of Collision)

S/B vessel altered course to Port side 4 degree (from 177 degrees, one minute before now).

N/B vessel altered course to Port Side 13 degrees (from 359 degrees, 2 minute before now),

• Two vessels course line are crossing (end to end case in COLREG). In night time, this course change can be verified by fore and aft Mast Navigational Light alignment of N/B vessel unless obscured by fishing vessels in group.
• There is an important issue of “How to verify the Ocean Going vessel from fishing vessels in night time?”
• Two ship distances is 4.0 Nautical Miles.
• Collision Point is expanded to Possible Area of Collision. Diameters is 667 Meters ( 2 ship’s length of N/B vessel).

8. Time 16:36:21 (3.5 minutes before TOC Time of Collision)

S/B vessel altered course to Port side 1 degree (from 177 degrees, 1.5 minute before now).

N/B vessel altered course to Port Side 16 degrees Slowly (from 359 degrees, 2.5 minute before now),

Rate of Turning is 6.5 degrees per minutes, very slowly.

• Two vessels course line are end to end (head on exactly).
• Two ship distances is 3.5 Nautical Miles.
• Collision Point is expanded to Possible Area of Collision. Diameters is 667 Meters ( 2 ship’s length of N/B vessel).

9. Time 16:36:51 (3.0 minutes before TOC Time of Collision)

S/B vessel altered course to Port side 1 degree (from 177 degrees, 2 minute before now).

N/B vessel altered course to Port Side 19 degrees Slowly (from 359 degrees, 3 minute before now),

Rate of Turning is 6.1 degrees per minutes, very slowly.

• Two vessels course line are crossing each other.
• Two ship distances is 3.0 Nautical Miles.
• Collision Point is expanded to Possible Area of Collision. Diameters is 667 Meters ( 2 ship’s length of N/B vessel).

10. Time 16:37:11 (2.8 minutes before TOC Time of Collision)

S/B vessel altered course to Starboard side 13 degree (from 176 degrees, 40 seconds before).

Rate of Turning is 18 degrees per minutes, increased quickly

N/B vessel altered course to Port Side 6 degrees quickly (from 340 degrees, 20 seconds before now),

Rate of Turning is 18 degrees per minutes, increased quickly

• From end on situation, both vessels increase turning rate very quickly to 18 degrees per minute in this stage.
• This is not the risk they want to involve. This is the difference of Maneuverability make the things complicated.
  • This is the decision S/B vessel made one minutes before

(Faster and shorter, one minute distance = 592 Mtrs ,  592/292 Mtrs = 2.03 ship’s length),

• where is the decision N/B vessel made two minutes before

(slower and longer, two minute distance = 691 Mtrs,  691/334 Mtrs = 2.07 ship’s length)   

• Two ship distances is 2.8 Nautical Miles.
• Both vessels are at Breaking Point of course change which mean vessel’s bow depart from her original course line..
  • Collision can still be avoid if S/B vessel understand that N/B vessel need two minutes to steady the vessel and
  • Another two minutes more to go back to original course of 352 degree with no collision at 35: 21 Hours which
  • Is 2 + 2 =4  is Four minutes for S/B vessel to 352 degrees Course Again and clear of collision point, where
  • Now is only Three Minutes Time to Collision (TCPA),
  • Stop Engine Now is best choice for S/B vessel to go back Safety Speed to avoid the collision. Instead of
  • Waiting N/B vessel can clear of the way.
• N/B vessel should use “Hard Starboard” Rudder to avoid collision first once noticed heading change of S/B vessel.
  • Although S/B vessel Relative Bearing fall to starboard side of own ship, S/B vessel navigational lights alignments still have noticeable change can indicate S/B vessel had altered course to starboard.

11. Time 16:37:31 (2.5 minutes before TOC Time of Collision)

S/B vessel altered course to Starboard side 13 degree (from 176 degrees, 40 seconds before now).

N/B vessel altered course to Port Side 9 degrees quickly (from 340 degrees, 40 seconds before now),

  Rate of Turning is 12 degrees per minutes, decreased

• Two vessels course line are crossing each other.
• From 20 seconds before, both vessels turning rate decrease from 18 to 12 degrees per minute now.
• It is doubtful both vessels engaged in Hand Steering now?
• Two ship distances is 2.5 Nautical Miles.
• Collision Point is expanded to Possible Area of Collision. Diameters is 667 Meters ( 2 ship’s length of N/B vessel).

12. Time 16:38:01 (2.0 minutes before TOC Time of Collision)

Last chance to avoid collision.

S/B vessel courses no change from 37:31 (30 seconds before).

N/B vessel altered course to Port Side 13 degrees quickly (from 340 degrees, 70 seconds before now),

  Rate of Turning is 12 degrees per minutes, the same.

• Two vessels course line are crossing each other.
• Two ship distances is 2.0 Nautical Miles.
• The difference of Maneuverability makes the decision different. S/B vessel may
  • S/B vessel two minutes before, (two minute distance = 1184 Mtrs , 1184/292 Mtrs = 4.06 ship’s length), Vessel have the option to Rudder Cycling and stop the engine at the same time.
  • Faster means vessel can get more speed difference in Stop Engine and
  • Shorter means vessel can have more favorable Advance distance ahead for course change. 
  • N/B vessel two minutes before, (slower and longer, two minute distance = 691 Mtrs,  691/334 Mtrs = 2.07 ship’s length) N/B vessel is helpless but stop engine with “Hard Over Rudder” (no turning effect but to hope for swag down some speed).

13. Time 16:38:31 (1.5 minutes before TOC)

Both vessels speed Unchanged and Unaware of other vessel movement.

S/B vessel altered course to Starboard side 5 degree (from 187 degrees, 30 seconds before).

Rate of Turning is 10 degrees per minutes.

N/B vessel altered course to Port Side 18 degrees (from 340 degrees, 100 seconds before now),

  Rate of Turning is 12 degrees per minutes, the same.

• Two vessels course line are crossing each other.
• Two ship distances is 1.5 Nautical Miles.
• S/B vessel continue the slow turning rate of 10 degree per minute after 30 seconds course no change.
  • Not knowing the collision is imminent now.
  • Not knowing N/B vessel had kept turning rate of 12 degree per minute for 1.5 minutes already.
  • Not knowing own ship exposed midship section to coming vessel.
  • Not knowing own ship course change to starboard side made the collision inevitable.
• N/B vessel continue the Port side turning.

14. Time 16:39:01 (1.0 minutes before TOC)

Both vessels speed Unchanged, S/B vessel already inside the Collision Area.

S/B vessel altered course to Starboard side 21 degree Quickly (from 187 degrees, 60 seconds before).

Rate of Turning is 40 degrees per minute, Very VERY quickly.

• This is the decision S/B vessel made one minutes before, two minute before collision.
• Once the turning begin, the turn should carry onto

N/B vessel altered course to Port Side 7 degrees Slowly (from 327 degrees, 60 seconds before),

Rate of Turning is 7 degrees per minutes, slow down.

Suspected turning control by Auto Pilot or Ecdis.

• Two vessels course line are crossing each other.
• Two ship distances is 1.5 Nautical Miles.

Relative Bearing change of N/B vessel, Bow bearing (green line) remain steady is Possible Collision Contact Point (red circle) and Stern bearing increased (Purple Line) means OK.

Relative Bearing change of S/B vessel, Bow bearing (green line) decrease is OK and Stern bearing almost unchanged (Purple Line) means Possible Collision Contact Point (red circle).

15. Time 16:39:31 (0.5 minutes before TOC)

Both vessels speed Unchanged

S/B vessel altered course to Starboard side 1 degree, no change (from 209 degrees, 30 seconds before).

Rate of Turning is 2 degrees per minute, Maybe vessel is conducting Rudder Cycling without Stop Engine.

N/B vessel altered course to Port Side 9 degrees Slowly (from 327 degrees, 90 seconds before),

Rate of Turning is 6 degrees per minutes, slow down. Maybe vessel is conducting Auto Pilot turning without Stop Engine. The turnings never stop in N/B vessel.

• Two ship distances is 1.5 Nautical Miles.

Relative Bearing change of

• N/B vessel Bow bearing (green line) No change and
• S/B vessel Stern bearing (Purple Line) No change
• Coming vessel relative bearing almost unchanged area is PCCP Possible Collision Contact Point (red circle).

16. Time 16:39:41 (0.5 minutes before TOC)

Both vessels speed Unchanged

S/B vessel altered course to Starboard side 31 degree Quickly (from 177 degrees).

N/B vessel altered course to Port Side 41 degrees Slowly (from 359 degrees),

• Two vessels course line are crossing each other.
• Two ship distances is 1.5 Nautical Miles.
• Reader can verify the statement of PCCP Possible Collision Contact Point (red circle) in here.
• The time for bridge team to hold on something is 5 seconds; if it is possible Bridge team should warning the Own Ship Crew by General alarm and Public Address system 30 seconds before Collision.

17. Time 16:39:51 (10 seconds before Collision). No change

18. Time 14:40:01 to 14:41:01 (Possible Collision Time)

Both vessels speed changed due to collision.

S/B vessel heading changed to 231 degree starboard side 22 degree quickly due to contact (from 209 degrees).

N/B vessel heading changed to Port Side 292 degrees quickly due to contact (from 318 degrees),

• S/B vessel bridge team should take precautions due to life is threaten by collision (incoming vessel bow relative bearing remained unchanged) with
  • obligation to warn his fellow crew on board if possible before collision
  • obligation to warn his fellow crew on board if possible after collision.
• N/B vessel should wait to see whether collided vessel is in immediate danger with
  • Obligation to remain ship hull contact without go Astern Engine immediately if possible after collision.
  • Obligation to warn his fellow crew on board if possible after collision.
  • Obligation to save other ship’s crew in water if needed.

19. Time 14:40:01 to 14:41:51 (110 seconds after Collision)

Both vessels speed dropped due to collision.

S/B vessel heading changed to 182 degree port side from 209 degrees, with Slow Ahead 9.9 Kts.

N/B vessel heading changed to Port Side 24 degrees quickly from 318 degrees, with Dead Slow Ahead 5.3 Kts.

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