Tecumseh Class Diesel-Electric Attack Submarine (SSK)
Type: Diesel Electric Attack Submarine
Displacement Surfaced: 1,750 tonnes
Displacement submerged: 2,130 tonnes
Length: 60m
Beam: 7m
Propulsion: 3x Diesels (5,000hp), 2 HDW/Siemens PEM fuel cells 120 kW, 1 Siemens Permasyn electric motor 1700 kW, 1x 7 bladed Pumpjet
Speed surfaced: 12 knots (burst), 9 knots (sustained)
Speed submerged: 25+ knots (burst), 20+ knots (sustained)
Range: 30,000km unrefueled
Test depth: 250m (operational) 400m(crush)
Max endurance(Electric motors): 150 minutes full speed, 110 hours at 3 knots
Hull construction:
Single hulled Titanium, HY-80 or HY-100 Steel construction. Pressure hull is further subdivided into 2 watertight sections (Engineering and forward). Outer hull maintains a 120mm thick rubber anechoic tile coating.
Crew compliment: 35 crew + 10 additional
Armament: 8 660mm Torpedo Tubes with 16 reloads
Countermeasures: 60 127mm Noisemakers, Advanced Electromagnetic Signature Reduction System
Sensors
PAC11 Passive/Active Sonar Array
PAC11 Towed Array
PAC11 Passive Mast Mounted Search Radar
PAC11 Active Mast Mounted Search Radar
PSC11 Telescoping Photonic Masts
Cost-700 million USD
The Tecumseh Class Diesel Electric Attack Submarine (SSK) was a design that was committed too as a export venture by the Philadelphia Shipbuilding Corporation, in a attempt by it to allow it to gain a foothold, no matter how small or big, in the Submarine Construction and Export market. The Submarine was directly based off of the German Built and Israeli used Dolphin Class Diesel Attack Submarine, with some influences from the last Diesel Attack Submarines the Americans ever built, the Barbel Class.
Armament and Electronics
The main and only armament of the Tecumseh class is its eight 660mm torpedo tubes, capable of firing torpedoes such as the American Mk48 ADCAP, or Missiles such as the UGM-109 Tomahawk and UGM-84 Harpoon. The choice to equip the submarine with 660mm torpedo tubes was made in order to allow for the submarine to have an ability to carry armaments that might differ in size from the torpedoes and missiles most would think of immediately that nations would use, such as the Mk48 and the UGM-84.
The electronics on the submarine are largely the same as found some Pennsylvanian Navy submarines, such as the Williamson Class Nuclear Missile Submarine (SSMN). This includes the same Photonic Mast and the same Sonar Systems, and a similar, but somewhat more compact version of the Radar mast, with a shorter effective range, accounting for the significant difference in size between the Williamson Class and the Tecumseh Class.
The vessel does not utilize a conventional periscope for the Captain or other officers to use in order to identify a vessel. It instead utilizes a Photonic Mast to transmit a digital image of the target from the Mast to a series of High Definition monitors around the control room of the submarine.
A photonics mast (or optronic mast) is a sensor similar in concept to a submarine periscope, except that it doesn't require a periscope tube thus freeing design space during construction and limiting risks of water leakage in the event of damage. A photonics mast replaces the mechanical; line-of-sight viewing system with digital equipment, similar to a digital camera array, and it has fewer locational and dimensional constraints than a traditional periscope.
Unlike a periscope, it need not be located directly above its user, and it requires only a small pressure hull penetration for cabling. This allows the photonics mast to be contained entirely within the sail of the submarine and means the control room need not be placed directly below the sail.
A photonics mast operates by rising above the water similarly to a telescoping car antenna and provides information through an array of sensors, such as high definition low-light and thermo graphic cameras. Images and information can be sent to display panels for analysis. The photonics mast can also support the navigation, electronic warfare, and communications functions of a conventional optical periscope mast.
The submarine utilizes a bow mounted Active and Passive Sonar system as well as a passive cable towed array system, located on the starboard side of the submarine amidships. The Towed arrays cable is almost a kilometer long, allowing it to get clear of noise from the submarine, and to detect other submarines or even surface ships from long distances. The systems are sensitive enough to pick up sounds more than 500km away, though, at these distances, accuracy is anything but good.
Propulsion
The submarines propulsion is that of a Diesel Electric Mix with an Air Independent Propulsion unit. Air Independent Propulsion (AIP) is a system that allows a Diesel-Electric Attack Submarine to significantly increase its underwater endurance from a few days in older versions of the Diesel Electric Boats, to a few weeks in the newer ones, a ability that previously only existed in Nuclear Powered Attack Submarines (SSN), allowing the Diesel-Electric powered Submarine, to, for the first time, be able to come near matching a Nuclear Powered submarine in endurance on patrol.
The Tecumseh Classes primary mode of propulsion is its 3 Diesel engines, producing a total of 5,000 horsepower, allowing the submarine to, at max power, be driven at over 20 knots submerged, and around 10 knots when surfaced. While the diesel is the primary mode of power for the submarine, the submarine is designed to use its batteries, with a lifespan of up to 110 hours at 3 knots, when it is submerged. In addition to its batteries, the submarine AIP, using the same systems for it as the German U-212A Class of Diesel Electric Attack Submarines, further increasing its underwater endurance, allowing it to come close to matching a Nuclear Powered boat in endurance.
The submarine can operate at high speed on diesel power or switch to the AIP system for silent slow cruising, staying submerged for up to three weeks without surfacing and with no exhaust heat. The system is also said to be vibration-free, extremely quiet and virtually undetectable.
Hull Construction
The submarine is made of an all titanium (Or HY-80 or HY-100 Steel, if requested) single hull construction split into 2 different compartments, Engineering and Forward. The choice of titanium was made in order to try to increase the submarines dive capability, in the event that any user of the vessel would use it in a blue water environment as well. While this would result in a increase of overall price for the submarine, it was decided that the extra cost thereof, would be worth it if the submarine were to prove to be any sort of an export success.
Export
The exportation of the Tecumseh Class Diesel Electric Attack submarine will be provided for on a largely non-biased basis, provided you are not at war with the Republic of Pennsylvania or any of the Republics good allies, or that are distinct enemies of the Republic. All nations will receive the Tecumseh Class as the price of $700mn per boat, with Domestic Production Rights for close nations only going for the price of $1 trillion (assuming a production run of just short of 1,500 vessels). Contracts are also open for use, in which the buyer will pay $680mn-$690mn per boat to be manufactored en masse by Pennsylvanian Shipbuilders at a discount.
Single Vessel-$700 million
Domestic Production Rights(Restricted): $1 trillion
Production contract: $680 million to $690 million per vessel.
