What level in the hierarchy would be required for an officer to be given such a responsibility? (Sorry, I just have no knowledge of military structure in any of the service branches.)
If it was a LT then they were either the Operations or Weapons Department heads. Generally the Chief Engineer doesn't stand deck watches although he would be qualified to.
The LTJGs would likely have stood 150-200 watches on the bridge as Junior Officer of the Deck (JOOD), as hands on training to become OOD.
I will note again that it is over 35 years since I last had the deck and I am doing this from memory.
One thing is bothering me here. Why weren't those in CIC screaming at the bridge about an impending collision? I was CIC Officer as a JG. There is one item drilled into EVERYONE who used the surface search radar, CBDR (Constant Bearing, Decreasing Range). If a radar contact is CBDR then there will be a collision unless someone reduces speed and/or changes course.
The Nautical Rules determine which ship is privileged and which ship is burdened. The privileged ship is required to maintain course and speed while the burdened ship must maneuver. This is important as you can't have both ships maneuvering and changing speed. However, if two ships get close enough that a collision is imminent then both ships are 'in extremis' and required to act to avoid a collision.
In this case the Fitzgerald was the burdened ship.
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