Russian Naval Question

I'm asking this question for an aviation project I'm contemplating doing, but I figured as it had to do with naval insignia, it was best asked to you folks who built floaty things

My question is regarding the Russian Navy jack (pre and post Soviet era).

Is it a white flag with a blue cross going out toward the corners? I've seen a picture of one. but I can't exactly remember for sure what it looks like. Was it the same prior to Socialism as it is post Socialism?

Any help would be great, even better if you could post a picture of one.

Thanks in advance