That is drilled into every one standing a bridge or CIC watch from the OOD down to the aft lookout. Even my Quartermaster of the Watch and Boatswain's Mate of the Watch understood that.
The OS on the surface search radar in Combat should have been screaming "CBDR" from the moment he first detected the contact's lack of bearing drift or if the contact would pass inside the minimum CPA (Closest Point of Approach).
The CICWO and JOOD had a duty to call for the Captain if they thought the ship was in danger and the OOD wasn't acting.
"Ceterum censeo Islam esse delendam."
Garde la Foi, mes amis! Nous nous sommes les sauveurs de la République! Maintenant et Toujours!
(Keep the Faith, my friends! We are the saviors of the Republic! Now and Forever!)
LonePalm, le Républicain du verre cassé (The Broken Glass Republican)
[ What part of CBDR (Constant Bearing, Decreasing Range) did they NOT understand? ]
Yes, excellent question.
I’ve seen a lot of people freeze in situations of even relatively mild things. Makes it hard for me to trust some folks.
With your CBDR question, it almost makes me think it was unmanned in some areas; trusted to autopilot. Hope we get to see an official report.
I learned “Constant Bearing Means Collision” in HS math class. ‘Course it could mean the opposite - if the range is increasing. Which would be pretty much excluded as a possibility if the magnitude of the bearing from the faster ship to the slower one is .GE. 90 degrees off the bow . . .