POR ship dynamics

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[pauljanaway1]

Hi pauljanaway1

I'm very sad to hear that. May I ask you what experence you have with vessel dynamics and behaviour? Are you a ship's officer/engineer/naval architect? I'm just curious to know what you think is wrong and why you compare the PoR to Titanic and Latitude.

Regards
Jacob

 am none of them i feel the the POR is slugish at turning but i did a test in game on a flat sea and at 15kn the POR has a slower turning speed taking 33 seconds to reach a turing speed of 30 degress where as at the same speed titaninc takes 15 seconeds to reach a turing speed of 30 degress

[TerryRussell]

Hi Pauljanaway1.

So what you really mean is that you, personally, don't approve of the changes?

You really need to make sure that you have sufficient competence before you claim something is wrong. If you don't like it, you should make it clear that it is your opinion, then that will avoid confusion.

Thanks. 

[NathanC]

I saw the PoR turning while using it (duuuhhh  ) and it reacts/turns quite quickly

[groennegaard]

am none of them i feel the the POR is slugish at turning but i did a test in game on a flat sea and at 15kn the POR has a slower turning speed taking 33 seconds to reach a turing speed of 30 degress where as at the same speed titaninc takes 15 seconeds to reach a turing speed of 30 degress

But that is how such a vessel behaves... 

For instance, a vessel like the DFDS Dana Sirena takes 30 seconds to turn 35 degrees. This is even at full speed so at 65% speed, that number will of course be lower.

I have similar data from other passenger and ro/pax vessels, so I believe the data you've measured is fair.

Regards
Jacob

[groennegaard]

I saw the PoR turning while using it (duuuhhh  ) and it reacts/turns quite quickly

Did you bring your stopwatch? 

You probably saw it turn when manouevering where all means were used to make the vessel turn. Using thrusters combined with one propeller going ahead and the other one astern, you will of course reach a ROT far beyond 30 degrees/min.

Jacob

[pauljanaway1]

it is my own opinone my first post reads

"i find that it is very poor i would even go to say worce than the titanic or latitude"


and then i showed that it turns slower. it might just be the titaninc was modeled wrong and the POR is right or the other way round all im saying is it seems very slow to turn for a moden ship

[NathanC]

Did you bring your stopwatch? 

You probably saw it turn when manouevering where all means were used to make the vessel turn. Using thrusters combined with one propeller going ahead and the other one astern, you will of course reach a ROT far beyond 30 degrees/min.

Jacob

I saw it turning out at sea, and it was quite fast

[groennegaard]

I saw it turning out at sea, and it was quite fast

If you make the model turn for a minute at full speed, ROT will be more than 83 degr/min - and that is quite fast... 

Jacob

[NathanC]

But when she was turning "fast" she was only turning about 20 degrees, and still doing it quickly

[groennegaard]

But when she was turning "fast" she was only turning about 20 degrees, and still doing it quickly

Yes, that will probably take 40-45 seconds if you push it to the limit, but they never do that as no officer would be proud of having cleared all the tables in the restaurant at once... Ship Simulator is better suited for such experiments and there the PoR will do a 20 degree turn in 40 seconds. 

Jacob

[NathanC]

hmmm, strange, i'm oretty sure it took about 5-10 seconds to turn 20-30 degrees, i was outide and looking down the port side of the ship when it did this

[TerryRussell]

hmmm, strange, i'm oretty sure it took about 5-10 seconds to turn 20-30 degrees, i was outide and looking down the port side of the ship when it did this

Hi Nathan.

OK, so to take the slowest rate according to your figures,
20 degrees in 10 seconds = 120 degrees per minute.
3 minutes to turn completely in a circle.

Or the fastest rate,
30 degrees in 5 seconds = 360 degrees per minute
1 minute to turn completely in a circle.

As Groennegaard says, watch all the plates going flying off the tables in the restaurant!

[groennegaard]

hmmm, strange, i'm oretty sure it took about 5-10 seconds to turn 20-30 degrees, i was outide and looking down the port side of the ship when it did this

That would be about 50% quicker than similar vessels for the slowest rate. Very fast indeed. Too fast I would say. I bet you had to struggle to keep upright...   

Jacob

[NathanC]

I will take a video to show you next time i visit her......

[groennegaard]

I will take a video to show you next time i visit her......

Great! I'll be looking forward to that. My compliments to your youtube slideshow. Always interesting to see pictures and videos from the ships we play with in SS... 

Jacob