The line in first bubble means "Taking a full turn by turning the helm". But I don't know how it's said in the Navy so, please do check it.

Full wheel to the portside
Not so sure about the English naval term too, but it means full turn to the right.

For starboard it's 取り舵いっぱい (torikaji ippai)

I wonder why it's always Ooi/Kitakami or Akagi/Kaga in one of these "shipgirl turned abyssal" stories?