Amazing eye for detail.
I will be sure to follow your advice when I get to my Scharnhorst... which may be soon
Moderators: BB62vet, MartinJQuinn, JIM BAUMANN, Jon, Dan K
I've no interest in Scharnhorst nor the underwater details at all, but in the spirit of instruction corrections, should those propellers be in that order?California Bound wrote: By now we are all probably aware of the poor quality of the instructions. Even so, I wasn't expecting to find an error first thing. I thought I would include pics of instruction corrections as I proceed. If this seems too stupid, please let me know, and I will stop including the instructions.
Dan.
Well there you go. My background is aeronautical engineering; this solution wouldn't have occured to me for a tri-engined aircraft. I now have something to look into.California Bound wrote:Hi Linz,
The propellers are numbered correctly. I don't know the science. The idea is that a propeller rotating out and down away from the hull is more efficient than one rotating out and up towards the hull. In this case, as Scharnhorst travels forwards, and is viewed from behind, her left propeller would be rotating counter clockwise and her right propeller(with blades set at the opposite angle) would be turning clockwise. In her case, they chose to have the center propeller turn counter clockwise too. So it's blade angle is the same as the left propeller.
Dan.
This is generally true. Of course, there are cases where it is not true where the effect is either absent or the opposite, and this depends on the hull aft body flow. Some naval ships have inboard rotating propellers so that noise and force fluctuations are less, at a cost of efficiency. Nowadays we can calculate the hull flow so well that we can get the flow to the propeller as symmetric as we'd want it and direction of rotation hardly matters (for efficiency).I don't know the science. The idea is that a propeller rotating out and down away from the hull is more efficient than one rotating out and up towards the hull.








































