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

Here is an assortment of large sharks that can be found in New Jersey waters, by no means all of them. These are more likely to be found inshore in coastal waters. Sharks are seldom a danger to divers, they seem to be put off by the noise and bubbles. Nonetheless, all should be treated with caution.

In all my many inlet dives, I have seen a shark once, and that was in inoffensive Smooth Dogfish. I have been told that they are sometimes seen from up on the bridge in Belmar, but even then they would probably be out in mid-channel, and far away from strange noisy bubbling scuba divers. However, one of the most famous shark attacks of all time took place in New Jersey - the 1916 Matawan Creek attacks. See Bull Shark for details.

The only one of these that you are ever likely to encounter in local ocean diving is the relatively inoffensive Sand Tiger, not the similarly named and extremely dangerous Tiger.

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