Propellers, Shafts & Rudders

propeller & rudder
modern brass propeller
A huge modern brass propeller ( from the SS United States ) on display.
shipwreck Delaware propeller
Looking down the prop shaft at the iron propeller on the Delaware. The narrow squarish blades indicate that this is a rather primitive 1880's model, unlike the more modern rounded prop on the Macedonia below.
shipwreck Macedonia propeller
The propeller on the Macedonia.
shipwreck Macedonia shaft mount
Propeller shaft bearing and mount on the Macedonia.
reef Venturo propeller
The propeller on the GA Venturo - a completely modern design. Note the wide, round blades.

Breaking a propeller shaft at sea can be a disaster. The propeller stops turning and becomes a drag, while the vessel's momentum carries it forward. The propeller slams backward, extracting the broken shaft and often mangling the rudder. This leaves a large hole open in the bottom of the vessel, directly into the bilges and machinery spaces. On a large vessel with a deep draft and a large shaft, the water comes in like a fire hose - uncontrollable.

The engine is soon disabled, and along with that the pumps, which in any case are probably not big enough to keep up with this magnitude of flooding. The outcome may take several hours, but it is inevitable unless maybe the Coast Guard can fly out a special de-watering pump on one of their big helos. Unlike a collision, storm, or rogue wave, there is usually plenty of time for an orderly abandon-ship, and there are seldom casualties if rescue is available.

Shipwreck Emerald
The "Emerald" fell victim to a broken prop shaft in 1873, and the Lady Gertrude sank the same way in 2016.
shipwreck Oregon steering quadrant
The fallen steering quadrant on the Oregon, perhaps 20 ft across.
shipwreck Tolten steering quadrant
Tolten steering quadrant
Tolten steering quadrant
The steering quadrant on the Tolten

Eastern Pickerel

Esox niger

Size
to 39"

Eastern or 'Chain' pickerels are deep olive-green on the back, shading to a creamy yellow on the belly. Olive green blotches are present within distinct black chain-like or interwoven markings on the sides. There is a distinct dark, vertical bar below the eye. The cheek and gill covers are completely covered by scales. The underside of the lower jaw has 14-17 branchiostegal rays. There are no recognized subspecies. However, they hybridize readily with redfin pickerels. They are distantly related to trout and salmon.

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