No photograph is shown for this exhibition. The museum displays an image only where it can show the object honestly.
About this date
A Han dynasty tomb model of a boat with a rudder is dated to the 1st century CE. European stern rudders appear in carvings and records from the 12th century.
About credit
Whether the European rudder was independently developed or arrived from Asia is debated.
Chapter II
The world before
Life before the Stern-Post Rudder
Ships were steered with large oars at the side, which grew unwieldy as vessels got larger.
II
The human achievement
How it came about
Shipwrights mounted a rudder on the stern post, controlled by a tiller or wheel. It acted directly on the water behind the ship and gave helmsmen far better control.
III
Understanding the invention
How it works
The Stern-Post Rudder, explained in two steps.
01
Step 01 of 02
Turning the water flow
Deflecting water passing the stern pushes the stern sideways, turning the bow.
Turning the water flow
Hinged to the hull
IV
The transformation
What changed for humanity
Seafaring
Bigger ships with deeper hulls could sail further.
Exploration
It complemented sails and the compass in long voyages.
Larger, heavier ships could be steered reliably, which supported long-distance voyages.
V
Before and after
Life before and after The Stern-Post Rudder
Before
Struggling with a side oar.
After
A tiller or wheel acting on a central rudder.
On larger screens, drag the divider (or use the arrow keys) to give more room to the world before or after.
The Han dynasty tomb model is one of the oldest clear depictions. It shows that shipbuilders had a workable rudder long before it was common in Europe.
Where accounts differ, this museum follows the documented record and says so.
