The Telligstedt Institute for advanced Ship Controllability

Rudder Insanity

Ships had rudders before they hat engines. When propellers were introduced, they were placed in front of the rudder.
That combination worked, for propulsion and for steering, and ships are mainly built this way today.
But is this combination effective? Apparently not, and the ship- builders know that.
When speed and efficiency really counted, they found other solutions:

But what would be the ideal solution? We have a ship with a propeller that produces a stream of high velocity water:
propeller stream

A good solution would be if we could direct this stream left or right for steering without causing too much losses due to friction:
Additionally there should be also directional controllability in reverse.

There are solutions that fulfil these requirements (e.g. Duct-Rudder, Thrust Reverser Rudder, GATE RUDDER),

but instead, today ships are built like this:
normal system
That means:
1. Losses due to friction are maximum:
- the rudder is in the area of the highest water velocity
- its shape does not respect the rotation of the propeller
(would be easy to do)
low drag rudder
2. In reverse there is no control

That is insane!