I am not sure of the version that has been published, my answer cannot be 100% as long as I don't know that. It should be of 24/08/10.
There is a small asymmetry too in the RPM and pitch curves of PoR, and there are problems with the keyboard controls, particularly that the keyboard controls of the bow thruster act on the stern thruster (and etc). You will not be aware of it too much, because both have the same characteristics and are symmetrically placed vs the centre of the ship. You can only be aware of it dynamically if you really pay attention.
So, PoR thruster 1 (in options) is the bow thruster, 2 is the stern thruster, but also left is right and right is left.
It could also happen that using the throttle keyboard controls, the thrusters will start : You should not only call the chief, but try to reset them as often as needed. Perhaps is it only for me, I use a G11 belgian azerty keyboard and don't know if it also happens for regular keyboards.
The propellers are CPP, rotating inwards, ahead is CCW for the starboard propeller (so left hand screw) and CW for the port one (right hand screw seen from behind).
It is a normal arrangement to maximise the turning effect due to the propwalk when backing. For propellers relatively close to the centre line, it also means that the thrust ahead that helps you turn due to the eccentricity of the propeller is thwarted by the propwalk in forward, meaning not much of the eccentricity effect, eventually fully hiding the fact that the propeller is to the side. Not a big problem, as the full flow of the propeller acts on the rudder, restoring your manoeuvrability. Another advantage is that you can more easily make way on one propeller if needed.
Turning astern, the propwalk is added to the eccentricity (if I dare say so), and it helps your ship to turn, QED.
Also, there is not necessarily much course stability when making way astern, and the steady rotation of 26°/min can be realistic. Once the ship turns either way, you must steer, why would you think you shouldn't? There is no guarantee that the ship course will be straightened while astern. More importantly, the whole steering system should be able to match the yaw up to (down to) the manoeuvring speed, but the rudder is very close to the pivot point and doesn't receive much help from the propeller. Also, the rudder as a foil is working in a reverse direction, and its stall angle is smaller, so that great angles are worse than angles smaller than the stall angle.
Coming back to the propeller, RPM and pitch vary simultaneously, as if controlled by a combinator, and the propellers keep turning slowly when the pitch is 0.
Regards,
Luc
