ship stopping distances

i wanted to run some numbers by you to see what is the most realistic ship slowing times in your opinion

i tested the battleship kongo from a 20 kt speed doing evasive manuvers and at a 15 kt speed and it will stop by just turning off its engines and drifting for the stoping test

these are the numbers i got for three different settings i tried:

stopping test one:
from 15 kts - 11 kts = 2 minutes
from 15 kts - 10 kts = 3 minutes 15 seconds
from 15 kts - 9 kts = 6 minutes
from 15kts - 8 kts = 10 minutes 10 seconds
from 15 kts - 7 kts = 15 minutes
from 15 kts - 6 kts = 20 minutes 30 seconds
from 15 kts - 5 kts = 26 minutes 45 seconds

evasive manuvers test: it slows from 20 kts to 10-12 kts when turning

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stopping test two:
from 15 kts - 11 kts = 4 minutes 30 seconds
from 15 kts - 10 kts = 7 minutes
from 15 kts - 9 kts = 10 minutes
from 15 kts - 8 kts = 13 minutes 45 seconds
from 15 kts - 7 kts = 18 minutes 20 seconds
from 15 kts - 6 kts = 24 minutes 15 seconds
from 15 kts - 5 kts = 32 minutes

it slows from 20 kts to 12-14 kts when turning


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stopping test three:
from 15 kts - 11 kts = 4 minutes 30 seconds
from 15 kts - 10 kts = 7 minutes
from 15 kts - 9 kts = 10 minutes
from 15 kts - 8 kts = 13 minutes 45 seconds
from 15 kts - 7 kts = 18 minutes 20 seconds
from 15 kts - 6 kts = 24 minutes 15 seconds
from 15 kts - 5 kts = 32 minutes

it slows from 20 kts to 14-15 kts when turning

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acceleration test for all three versions above:
from 1 kts - 5 kts = 15 seconds
from 1 kts - 10 kts = 1 minute 5 seconds
from 1 kts - 15 kts = 2 minutes 50 seconds
from 1 kts - 17 kts = 4minutes
from 1 kts - 20 kts = 6 minutes 15 seconds


in your opinion, which is the most realistic slowing speed in evasive manuvers and in your opinion, which is the most realistic slowing down speed from turning off engines?