Saturday, November 12, 2011

Pacific Vortex: hard rise on the planes and more


pg 14

"I then ordered all ballast blown and hard rise on the planes."
A ballast tank is a compartment within a boat, ship or other floating structure that holds water.

In submarines ballast tanks are used to allow the vessel to submerge, water being taken in to alter the vessel's buoyancy and allow the submarine to dive. When the submarine surfaces, water is blown out from the tanks using compressed air, and the vessel becomes positively buoyant again, allowing it to rise to the surface. A submarine may have several types of ballast tank: the main ballast tanks, which are the main tanks used for diving and surfacing, and trimming tanks, which are used to adjust the submarine's attitude (its 'trim') both on the surface and when underwater.

The stern planes, located near the propeller and normally horizontal, serve the same purpose as the trim tanks, controlling the trim, and are commonly used, while other control surfaces may not be present on many submarines. The fairwater planes on the sail and/or bow planes on the main body, both also horizontal, are closer to the centre of gravity, and are used to control depth with less effect on the trim.

When a submarine performs an emergency surfacing, all depth and trim methods are used simultaneously, together with propelling the boat upwards. Such surfacing is very quick, so the sub may even partially jump out of the water, potentially damaging submarine systems.

"I have ordered the men to resign the game."
A reference to the game of chess. When a player feels defeated, he will tip over his king and resign - or quit.

During WWII, eight men from the sunken submarine Tang swam 180 feet to the surface.
USS Tang (SS-306) was a Balao-class submarine of World War II. She was built and launched in 1943.

In her short career, the Tang sank 33 ships displacing 116,454 tons. Her commanding officer, Lieutenant Commander Richard H. O'Kane, received the Medal of Honor for her last two engagements (October 23, 1944 and October 24, 1944). Tang was sunk during the last engagement by a circular run of her final torpedo.

The ship sank in 180 feet of water. Several of the crew managed to reach the surface, and some of them survived to be captured by the Japanese. These were the first American submariners to escape a sunken submarine using a Momsen lung.

Of the 13 men who escaped, only nine reached the surface, and of these, five were able to swim until rescued. (Four had escaped the sub before it had even begun to sink). A total of 74 men were lost. Those who escaped the submarine were greeted in the morning with the bow of the transport sticking straight out of the water.

The nine survivors, including O'Kane, were picked up the next morning by a Japanese destroyer. The nine captives were retained by the Japanese in prison camps until the end of the war.

Our position is 32⁰ 43' 15" N- 161⁰ 18' 22" W
Latitude and longitude are often measured in degrees, minutes and seconds. The Eiffel Tower has a latitude of 48° 51′ 29″ N-- that is, 48 degrees plus 51 minutes plus 29 seconds. Or they may be measured entirely in degrees, e.g. 48.85806° N.

Latitude runs vertically - north to south. Longitude runs korizontally, east to west.

Dupree's final position for the Starbuck to travel the required distance, even at flank speed.
Flank speed is a nautical term referring to a ship's true maximum speed, beyond the speed that can be reached by traveling at full speed. Usually, flank speed is reserved for situations in which a ship finds itself in imminent danger, such as coming under attack by aircraft. Flank speed is very fuel-inefficient and often unsustainable because of engine overheating issues.

For example, the most economic speed of the Littoral combat ship is 20 knots (37 km/h; 23 mph) providing a range of 4,300 nautical miles (8,000 km; 4,900 mi), and endurance of 215 hours. This ship has a flank speed of 50 knots (93 km/h; 58 mph) but can only travel 1,500 nautical miles (2,800 km; 1,700 mi) at flank speed, exhausting its fuel in 30 hours. Thus, its "flank speed" consumes fuel over seven times faster than most economic.

Other speeds include one-third, two-thirds, standard, and full. One-third and two-thirds are the respective fractions of standard speed. Full is greater than standard, but not as great as flank. Emergency may not be any faster than flank, but indicates the ship should be brought up to maximum speed in the shortest possible time.

(One must speed up in order to "outflank" an opponent - the origin of the term.

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