Coming from ColinWright, I was more than half expecting this to be about kinematics of rotations and translation, well, screw theory, no Lie (*). Nonetheless th

Coming from ColinWright, I was more than half expecting this to be about kinematics of rotations and translation, well, screw theory, no Lie (*). Nonetheless this is going to be a good read. An Akula class submarine, mentioned in the article, an uncharacteristically silent Russian attack submarine, was leased out to the Indian navy. I remember that there were intelligence failure from the Indian side that led to the leak of propeller acoustics of 'some' submarines - data for the Kilo class and the Scorpenes were leaked, not sure about Akula. (*) In the off chance that the other screw is interesting too, there is this https://archive.org/details/theoryscrewsast00ballgoog https://archive.org/details/theoryscrewsast00ballgoog to take for a spin, especially for those who have enough time on their hands.