Hunter Wheel

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The Hunter Wheel was a device intended to improve the efficiency of propulsion in U.S. Navy steam-operated ships in the late 1830's and early 1840's. At the time, as ships were transitioning from sail to steam engine power, the understanding of the principles of efficiency of propulsion of steam engine-powered ships was in its infancy, and not totally understood.

The Hunter Wheel was an experimental device which attempted to improve such propulsion efficiency.

1 Vessel type
2 Design of the wheel
3 Testing of the device in USS Union
4 Result of test
5 Testing of the device in USS Water Witch
6 Subsequent testing of the wheel
7 See also
8 References

[edit] Vessel type

At the time there were two types of machine propulsion for steam operated vessels:

paddle wheel
screw (propeller)

The Hunter Wheel was intended to improve the efficiency of propulsion of the “paddle wheel” type of vessel.

[edit] Design of the wheel

The Hunter Wheel was named after Lt. William W. Hunter and consisted of a conventional paddle wheel drum placed horizontally within the vessel below the water-line. The paddles were so arranged as to project from a suitable opening in the side of the ship when at right angles to the keel. Water was kept from entering by a cofferdam placed around the paddle wheel drum and against the side of the ship.

[edit] Testing of the device in USS Union

The Hunter Wheel was tested in 1843 on the USS Union (1841) which had been modified to accept the device.

[edit] Result of test

It was discovered that Union’s engines wasted too much energy uselessly driving the paddle wheels through the water-filled cofferdam inside the ship.

[edit] Testing of the device in USS Water Witch

The device was testing also in USS Water Witch (1845) with the following result:

The wheels lost much of their power pushing water through the encased area inside the hull, forfeiting between 50 and 70 percent of their potential power.

[edit] Subsequent testing of the wheel

Testing continued through 1846 but failed to increase the efficiency of the paddle wheels.

The device was also used in the construction of USS Allegheny (1847) but it was found to be unreliable and inefficient, and Allegheny was later converted to screw-propelled.