No, they really don’t.
No stock I’ve worked, across almost ten types, carries emergency couplers. They’re something that’s brought out in a van when needed, and that’s incredibly rarely.
Carried on every train? I somewhat doubt that…
So, I’m aware of locos rescuing many units, just because you are not aware, doesn’t meant it doesn’t happen. I must of imagined the times freight locos have rescued trains for the TOc I work for, and my eyes must of been functioning wrong when they dragged a train into the platform I was stood on. Silly me!!
Just cos stock you’ve worked doesn’t have them, doesn’t mean that other stock doesn’t!! Again I must be imagining these emergency couplings locked in the cupboards of trains at my TOC, I’ll have to go back and ask what they are!
@DanNCL didn’t say that every train in the North East does carry emergency couplings, just that’s some do.