where's my knuckle
 

I have taken a lot of high speeds turns with full rudder but have never left a knuckle. I see the Russian boats leave knuckles so what am I doing wrong?

Knuckles are an interesting mechanic in the game. Sometimes they work and sometimes they don’t. I find that knuckles are easier to perform above or just below the surface duct. The deeper you go, the faster you need to be traveling. Additionally, make sure you are full rudder in one direction before going full rudder in the other. It took me a little while to figure that out using my keyboard, but when I use my heading hotkey “H” to make extreme course changes, I can pop a knuckle fairly easily. Just play around with it, it’s kind of a feel thing. Once you know it, they’re much easier to pull off.

Thanks CJMars I'll keep at it. One thing I may have been doing wrong is only given hard rudder in on direction. I did not shift my rudder. Can't wait to see it happen and see if it helps.

I have indeed found that giving a little rudder in one direction and then full rudder in the other direction is a reliable way to produce a knuckle. Also: I have found that flank speed (and I mean the speed you are actually making, not just what you ordered) is crucial to be able to produce a knuckle every time. If you're evading an enemy torpedo, things have already gone south enough for you not to care about noise for the moment.