Search results
Results from the WOW.Com Content Network
Noise generated on board ships and submarines can have far-reaching effects on the ability of the vessel to operate safely and efficiently. Military vessels in particular need to be quiet to avoid detection by sonar , so many methods have been used to limit a vessel's noise signature.
This noise decoyed the acoustic torpedoes away from the rear of the ship into a circling pattern around the noise maker (which was too small to strike) until the torpedo ran out of fuel. The noisy Foxer had the disadvantage that it also prevented the ship's own ASDIC from detecting any other U-boat nearby that could approach the convoy. [6]
The outdrive unit of a boat with sterndrive. A sterndrive or inboard/outboard drive (I/O) is a form of marine propulsion which combines inboard power with outboard drive. The engine sits just forward of the transom while the drive unit (outdrive or drive leg) lies outside the hull.
Radiated noise is the noise generated by a ship that has an effect on other ship's sensors, especially submarines. The Masker-Prairie countermeasure systems are key elements in this program to reduce radiated noise and self-noise that are not reduced by controlling the sounds at their source or their transmission to the hull. [2]
A simple 3 blade toroidal propeller. A toroidal propeller is a type of propeller that is ring-shaped with each blade forming a closed loop. The propellers are significantly quieter at audible frequency ranges, between 20 Hz and 20 kHz, while generating comparable thrust to traditional propellers.
Grinding is prohibited on the side of a typical (disk-shaped) bench grinder wheel, which is designed for grinding on the periphery only. Grinding on the side of a wheel can cause the wheel to explode. Some tool and cutter grinders have cup-shaped wheels designed to do grinding on the side.
In Klein’s case, a Postal Service spokeswoman said, the problem is the road. Hillman Ridge is paved but narrows to a width slightly larger than a pickup truck as it approaches Klein’s property.
The first submarine decoys were the German Bold fitted to U-boats of World War II. These were a pellet of calcium hydride in a simple metal container. On contact with sea water, the calcium hydride decomposed to produce a trail of hydrogen gas bubbles that acted as a bubble curtain and reflected ASDIC impulses to produce a false target.