Paddleducks
Paddler Information => Research => Topic started by: Dinosaursoupman on April 01, 2008, 04:13:55 PM
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Hey PD's
While engaged in my daily routine of searching the internet for things of interest, I happened upon an unusual vessel that reminded me of an earlier thread. Someone had asked if a submarine would work with a paddlewheel. The general consensus was 'not likely'. Then I found the USS Alarm, an experimental torpedo boat built in 1873.
As shown in one of the following pictures she's propelled by what is known as a "Fowler Wheel". Evidently the vanes are cam activated. As the wheel rotates about it's axis, a cam follower rides upon a cam. For approximately 270 degrees of that rotation the vanes lie in the plane of rotation. But for 90 degrees or so, the vane is forced out by the cam so that it is perpendicular to the plane of rotation, hence pushing the water in a manner similar (but not exactly like) a feathering paddlewheel. The Alarm would turn by rotating the cam so that the vane was opened to correspond to the direction the vessel needed to go. Theoretically, the vessel would have been able to turn within it's own length.
She was a one-off vessel that proved unsuccessful for her designed intent, yet she remained in existence for nearly 30 years. Like the Monitors of her time , technology soon overtook her and made her obsolete. But she did leave us with another possible "next project".
Enjoy, Randy the Dinosaur Soup Man
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This is obviously an amazingly early predecessor of what is known today as the Voith-Schneider Propeller (see http://en.wikipedia.org/wiki/Voith_Schneider_Propeller )
Regards, Moritz
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Just stumbled across this topic while looking for info on feathering wheels and thought I'd add my two bits for the record...
The Fowler wheel did indeed provide great maneuverability, the Alarm was able to turn in 1.5 lenghts. However, it failed to provide speed, which is rather crucial in a torpedo boat. After lingering for some years, the Alarm underwent a substantial overhaul, which included replacing the Fowler wheel with a Mallory steering screw. This contraption looked and worked much like one of those swiveling fans you encounter in hot climes. It preserved the ship's maneuverability, but didn't add any speed. The Alarm lingered some more and was eventually sold for scrap in 1898. Here's my 1/250 scale model of her:
(http://www.waldenfont.com/papermodels/images/alarm.jpg)
(http://www.waldenfont.com/papermodels/images/large/alarm_001.jpg)
(http://www.waldenfont.com/papermodels/images/large/alarm_003.jpg)
(http://www.waldenfont.com/papermodels/images/large/alarm_002.jpg)
(http://www.waldenfont.com/papermodels/images/large/alarm_004.jpg)
Cheers,
Oliver
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Well Oliver what can one say. What a fantastic model