Sailed4seas的部落格

Ex 04-02

Ownship speed is 18.6 Knots and course is 063.8 degrees at beginning. ​

The situational awareness is:

• With three minutes vector length in 18.6 Knots, this vector is about 9 cables distance as above. (skill by knowing  three minutes run)
• Ownship have two crossing vessel at starboard side (red circle), distance unknown. (sighted)
• One overtaken vessel at starboard side has same speed as ownship. (skill by comparing vector length)
• Ownship have three crossing vessel at port side (yellow circle), distance unknown. (sighted)
• One overtaken vessel at port side slower than ownship. (skill by comparing vector length)

The situational awareness with 6 minutes speed vector is:

• One port side crossing vessel will be at ownship bow after three minutes. ( skill by observing target vessel speed vector touched our heading at three minutes (yellow square))
• One starboard side crossing vessel will be at ownship bow after 4 minutes. ( skill by observing target vessel speed vector touched our heading at 4 minutes)

The situational awareness with 9 minutes speed vector is:

• Ownship have one collision point with crossing vessel at starboard side (Red Square), after 7.5 minutes or so. (sighted)
• Another crossing starboard side vessel has no collision risk as 9 minutes speed vector has no collision point. (sighted)
• One crossing vessel at port side will be at ownship bow after 7.0 minutes or so (Pink Square). (sighted)

Overall situation awareness is:

• Ownship have to take care of three vessels around but no collision risk right now.(action)
• Ownship has to give way (avoid arriving red square area at same time with target vessel)  if starboard crossing vessel keeps current speed and course.(action)
• Does Port side crossing vessel keep his course after crossed separation line? (suspect)
• Forget other slower vessels, it is no harm can be done.(suspect)

After 01minutes exercise time lapsed:

Ownship speed is 16.5 knots which had reduced from 18.6 kts with engine output reduced at beginning.

Ownship course is altered to port side 1 degrees to 062.8 from 063.8 degrees with hard rudder angle “port ten” used.

The situational awareness is:

• Port side crossing vessel will pass ownship bow after 1.5 minutes. (skill)
• One overtaking vessel at starboard side is faster than ownship will pass ownship bow after three minutes (Yellow Square). (skill)
• Ownship have one crossing vessel at starboard side has collision risk after 6 minutes (red square). (skill by using 6 minutes vector)
• Yellow Square is a collision point for two vessels course line crossed, but it is not a collision case for collision line (3 minutes speed vector line) had not crossed. (statement)
• Red square has Collision point and collision line coincided at same time, Collision Risk is for sure. (golden rule)
• One overtaken vessel at port side is still slower than ownship. (skill by comparing vector length)
• One crossing vessel at port side will pass ownship bow after 6 minutes (blue square). (skill by estimating 6 minutes speed vector direction)

After 02minutes exercise time lapsed:

Ownship speed is 14.5knots which had reduced from 16.5, 18.6 kts with engine output reduced to 15 % at beginning.

Ownship course is altered to starboard side 4 degrees to 066.4 degrees from 062.8, 063.8 degrees with rudder angle “starboard 15” used.

The situational awareness is:

• Ownship reduced engine output decisively and used rudder cycling with proper control of heading. (sighted)
• Port side crossing vessel will pass ownship bow after 1.0 minutes (mobile 1). (skill)
• One overtaking vessel at starboard side is faster than ownship will pass ownship bow after 1.5 minutes. (skill)
• Ownship have one crossing vessel at starboard side will be at ownship bow after 5 minutes (pink square). (skill by using 6 minutes vector)
• One crossing vessel at port side will pass ownship bow after 5 minutes (pink square). (skill by estimating 6 minutes speed vector direction)
• One overtaken vessel at port side is still slower than ownship. (skill by comparing vector length)

After 03minutes exercise time lapsed:

Ownship speed is 13.2knots which had reduced from 14.5, 16.5, 18.6 kts with engine output reduced to 15 % at beginning.

Ownship course is steady in 066.4 degrees from 062.8, 063.8 degrees with rudder angle “starboard 15” “Starboard 10””starboard 5”used.

The situational awareness is:

• Ownship reduced engine output decisively and used rudder angle needed for proper control of heading. (sighted)
• Port side crossing vessel and overtaking vessel at starboard side is at ownship bow now. (sighted)
• Ownship have one crossing vessel at starboard side will be at ownship bow after 3 minutes (sighted).
• One crossing vessel at port side will pass ownship bow about 4 minutes whatever. (sighted)
• One overtaken vessel at port side seems OK. (sighted)
• No ship is in doubt Now. (sighted)
• By reducing speed effectively with rudder cycling can save almost all problems. (suspect)
• Reduce speed is not the same as reduce engine output. (statement)
• Reduce speed cannot by reduce engine output only. (statement)

After 06minutes 32 seconds exercise time lapsed:

Ownship speed is 9.3knots which had reduced from 13.2, 14.5, 16.5, 18.6 kts with engine output reduced to 15 % at beginning and further reduce to 0% at 04 minutes time.

Ownship course is steady in 068 degrees from 066.4, 062.8, 063.8 degrees with rudder cycling twice.

The situational awareness is:

• Ownship reduced engine output decisively and used rudder cycling twice. (sighted)
• No ship is in doubt Now. (sighted)
• Situation is strikingly easy compare with last scenario Ex 04-01. (by proper knowledge and skill)
• By reducing speed effectively with rudder cycling can save almost all problems. (suspect)
• Reduce speed is not the same as reduce engine output. (statement)
• Reduce speed cannot by reduce engine output only. (statement)

End of Ex 04-02