I think that the main idea of the Dean Drive was to convert angular to linear momentum but it is hard to find information of how it was suppose to work. In my own work I spent five years trying how to convert angular to linear momentum. I had an idea called Centrifugal force Bucking Corriolis Coupled drive. I built a model that just barely increased the angular momentum by bucking a weight back down a spinning shaft and no propulsion was observed. I gave up the idea after awhile as I thought it wouldn't work ultimately. Since then I have had a thought that if I could keep the weight from being spun back out for more than 90 degrees that it might work after all, and the propulsion would be 90 degrees away from the direction I thought it would have when I first got the idea. but it wouldn't be an easy thing to do.