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239 Cards in this Set
- Front
- Back
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Mass defect
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Discrepancy between a nucleus mass and the mass of its individual particles.
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Fission is best described as:
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The splitting of a heavy nucleus, releasing neutrons, energy and fission products.
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Steam is produced on a nuclear power ship by:
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Using hot water from the reactor to boil secondary water at a low pressure.
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The _________ acts as a moveable, lower, pressure tight boundary in diesel energy. It harnesses the power from combustion.
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Piston
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The fuel injector in a diesel engine sprays fuel into:
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When pistons at the top at the start of the power stroke.
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The is ________ open during the intake stroke>
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Intake valve
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Ignition occurs in the diesel engine:
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Injecting diesel fuel into air above the auto-ignition.
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A puddle of oil is on the deck being heated by machinery below. In order for the oil to combust, it must be:
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Above the auto-ignition temperature.
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The combustor:
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Adds energy to compressed gases for later expansion
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The afterburner works by:
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Injection additional fuel into the gas stream after the turbine and at the thrust nozzle
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The ________ forces more oxygen into the combustor on a gas turbine.
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compression
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Turbine on a single-shaft gas turbine:
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Spins the compressor and other devices
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Single shaft gas turbines are typically used for:
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generating electricity in naval applications
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On a gas turbine, the heat rejection phase of the Brayton cycle takes place:
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Overboard in the atmosphere.
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An accumulator:
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Stores potential energy
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The pump on a shipboard hydraulic system serves to:
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Refill the accumulator
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The bypass valve on a typical hydraulic system:
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Pumps oil to the vent and supply tank once the accumulator is full but before the pump turns off.
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The component in the refrigeration cycle transfers heat to seawater:
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Condenser
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The TXV in the refrigeration cycle refers to:
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Automatically throttle (adjust) the flow of refrigerant to maintain the cooling capability.
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Refrigerant is hazardous because:
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Displaces oxygen in the lungs.
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Lube oil does not:
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Eliminate wear of metal surfaces
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Sun-cooling refers to:
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The temperature difference between the condensate temperature and the liquid saturation temperature for a given pressure.
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A vessel with one outlet near the top is filled with a hot liquid water and vapor water mixture and is being heated; lowering the pressure in the vessel:
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Lower partial pressure of water vapor, resulting in more vigorous boiling.
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Vibrant reducer is a special type of kingsbury thrust bearing that uses oil backed cylinders to absorb shock transferred into the thrust…of bearing:
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True
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Increasing signal strength to over power jammer noise is an example of: .
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Burnthrough
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Which information can be gathered directly from ES?
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Bearing, PW, PRF, Frequency
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Angle deception is accomplished by retransmission of the pulse onto the antennas:
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side lobe
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What is not a design requirement fir ES recovery?
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Long range emitter.
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Missile guidance is in three phases:
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Boost, mid course, terminal
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Missile guidance must have high accuracy as well as fast response guidance signal in the
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terminal phase
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Command comes from sources outside the weapon:
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Command guidance
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Which of the following is not a part of the detect to engage sequence?
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Propulsion employment
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Fire control deviation that results from energy loss as weapon makes contact with atmosphere:
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drag
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Displacement of a projectile from original line of fire mainly due to the effect of the rotation of the projectile:
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Drift
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What refers to bearing of a gun?
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Train
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Torpedo is launched from:
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impulse launcher
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Explosive propellant train:
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Primer, Igniter, Propellant
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Which of the following propulsion systems allows for space?
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Rocket motor
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________________ measures bearing drift and passes information to computer that generates steering commands to allow…
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Proportional navigation.
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Weapon is guided so that it remains on the line joining the target and point of control:
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line of sight
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Three types of self contained guidance systems are:
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inertial, terrestrial, and GPS.
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Variable homing logic, slow moving targets relative to missile speed:
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pursuit
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Warhead is characterized by the ejection of a high velocity molten jet followed by a slug:
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shaped warhead
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Which is not a destructive effect of an underwater blast?
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Vortex reaction
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Torpedo set to a snake search or a helical search pattern is an example of:
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Programmed preset
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Safeing and arming:
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Parallel: Target detecting
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Weapon transmits and receives on it’s own:
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Active homing
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Least amount of muzzle loss:
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long barrel
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Which characterizes a blast warhead?
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Blast produces heat and over pressure followed by suction and under pressure.
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High explosive train:
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detonator, booster main charge.
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SCRAM
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An emergency action in which the control rods of a nuclear reactor are rapidly inserted in order to absorb excess neutrons and stop the fission process.
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Critical state
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Neutrons resulting from fission go on to cause exactly one fission
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Subcritical
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A condition of an decreasing number of fissions as time goes on.
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Supercritical
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A condition of an increasing number of fissions as time goes on.
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Controlling fission
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The control rods work by absorbing neutrons, thereby preventing those neutrons from initiating additional fissions.
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Changing ship's speed on a nuclear powered ship
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A throttleman opens or closes throttles to adjust the flow of steam into the propulsion turbines, which will change turbine speed due to the change in steam velocity.
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Reason for primary/secondary plants
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By physically separating the two systems, we prevent all the bad particles created in the reactor from leaving the reactor plant.
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Why are confined spaces in nuclear enginerooms safer to work in?
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1. A smaller reactor minimizes amount of piping in contact with radioactive particles
2. Pipe bends, valves, and other porous materials are susceptible to areas of low flow, where contamination will settle. |
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Good daughter
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A cell is irradiated, but splits and produces healthy cells
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Bad daughter
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A cell will divide and produce a daughter cell that has damaged DNA. This mutated cell may reproduce and continue to cause damaged cells to grow in the human body, often leading to cancer.
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Piston, diesel engine
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The moving metal component that seals ups the enclosed volume in a cylinder. The piston moves up and down to transmit power from combustion.
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Crankshaft, diesel engine
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The crankshaft translates the up and down motion of the connecting rod to a rotational motion via connecting rod attachment points offset from the center of the crankshaft rotation.
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Connecting rod, diesel engine
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The connecting rod connects the piston to the cranksaft. It transfers the up and down motion of the piston to the crankshaft.
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Camshaft, diesel engine
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A shaft with egg shaped lobes that control the timing of the intake and exhaust valves.
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Intake valve, diesel engine
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A valve which opens to allow fresh air(and more importantly oxygen) into a cylinder to reset the combustion cycle.
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Exhaust valve, diesel engine
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A valve which opens to allow exhaust gasses to leave the cylinder after combustion...
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Spark plug, diesel engine
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A ceramic and metal ignition device, that uses an arc of electricity to ignite air-fuel mixtures in combustion engines where the temperature is below the auto-ignition temperature.
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Pushrod/lifter, diesel engine
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A pushrod (or lifter depending on engine design) takes the roational motion of the camshaft and translates it to a linear motion in order to open and close the intake and exhaust valves in the proper timeing. Each valve per cylinder will have its own pushrod or lifter. Pushrods are used in pushrot engines, and lifteres are used in overhead cam engines.
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Overhead Valve vs Overhead Cam Engine
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Overhead cam engines have one camshaft mounted on the top of each row of cylinders. It is the lobes on these camshaftes that rotate around and open the intake and exhaust valves. On an overhead valve engine, a shingle camshaft is mounted between the two rows of cylinders; the lobes on the cam actuate pushrods which in turn open the valves. Overhead valve engines are older and often less efficient, but are smaller in size relative to their displacement.
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Flash point
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The temperature at which a fuel can be made to ignite. Requires and outside source of ignition.
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Auto-Ignition Temperature
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A temperature above the flash point; fuel in oxygen will ignite on its own. Requires no outside source of ignition.
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Steps of a four stroke cycle engine
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1. Intake
2. Compression 3. Power 4. Exhaust |
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Intake, four stroke-cycle
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A cylinder is driven down; a misture of fuel and air is sucked in through the intake valve.
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Compression, four-stroke cycle
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The cylinder is driven up by another cylinder firing. The fule/air mixture is compressed.
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Power, four-stroke cycle
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The spark plug in the cylinder fires, igniting the mixture.
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Exhaust, four-stroke cycle
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The cylinder is driven down (forcing another cylinder up). Exhaust is expelled out of the exhaust valve.
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Controlling speed of diesel engine
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speed is controlled by putting more fuel/air mixture into the engine. Fuel flows through a butterfly valve in the intake manifold (piping that brings fuel to the cylinder head, where the valves sit) and is injected through the fuel injectors.
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Steps of the Brayton Cycle
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1. Intake
2. Compression 3. Combustion 4. Expansion (power) 5. Exhaust |
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Intake, Brayton cycle
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Air is sucked into the compressor
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Compression, Brayton Cycle
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Air is gradually compressed as it travels farther into the engine (as the blades in the compressor become smaller and closer together).
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Combustion, Brayton Cycle
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Air is mixed with fuel (from a fuel injector) and ignited.
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Expansion, Brayton Cycle
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As the hot gases expand to exit the engine, they turn the turbine, which is geared back to the compressor (it turns the compressor).
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Exhaust, Brayton cycle
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Hot gases excape through the back of the engine.
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Advantages of gas turbine engines
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1. Weight reduction of 70%
2. Compact, little or no cooling water required 3. Reduced manning requirements 4. Quicker response time 5. Faster Acceleration/deceleration 6. Modular replacement 7. Less vibrations 8. Less vibrations 9. High reliability |
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Disadvanteges of a gas turbine engine
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1. very inefficient at low partial loads
2. Not easily reversed 3. Many parts under high stress 4. High pitched noise (high energy - long range) 5. Needs large quantities of air 6. Large quantities of hot exhaust (IR target) 7. Cannot be repaired in place |
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Single Shaft Gas Turbine
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In a single shaft gas turbine there is only one shaft/turbine. This shaft is directly attached to the compressor and the machinery the gas turbine is running. This means that the turbine, compressor, and machinery all run at the same rpm. Single shafts efficiently operate at constant speeds.
Used to produce electricity in the US Navy |
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Split Shaft Gas Turbine
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A split shaft is never connected and is only coupled aerodynamically, meaning the exhaust gasses that run the first turbine can turn the second turbine at a different speed. Usually applied as generator on first shaft and propulsion on the second shaft. Split shaft is best where speeds and loads vary. The power shaft is decoupled from compressor-aerodynamically coupled; there is no physical connection between the two shafts, which allows both to operate at efficient speeds (not the same).
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Changing speed of gas turbine engines
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The main propulsion turbine must maintain a minimum speed to susteain operation (e.g. 5500 rpm). Therefore, since the turbine is connected to the propeller through a fixed set of reduction gears, the propeller must maintain a minimum speed. To change speed, more fuel/air is injected into the engine.
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Distillation plants
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Distillation uses evaporation to purify water. Water is boiled off the seawater and condensed as pure water. Reverse osmosis pressurizes water and forces it through a semi-permeable membrane which filters out impurities. This is the more modern method for purifying water.
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Reverse Osmosis units
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Work by putting pressure on the salt water side of the membrane with the opposite side at low pressure. Water flows through, salt doesn't, resulting brine is pumped overboard (flushed out by RO unit pump providing more seawater). Fresh water sent through additional membranes for extra purity.
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Pascal's Law
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Pascal's law states that any fluid confined to a container will exhibit the same pressure equally throughout the container.
P=F/A |
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Accumulator, Hydraulic component
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A pressurized cylinder that accumulates hydraulic fluid, allowing it to be pumped to the solenoid valves as it is needed. Fluid is replenished in the accumulator when it is not being drawn.
Stores potential energy. |
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Bypass Valve, Hydraulic component
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Connected to the pump, supply tank and accumulator of a basic hydraulic system. It allows for fluid to be directed to the accumulator as needed, or back to the supply tank is the accumulator is full.
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Reserve tank, Hydraulic component
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Tank that extra hydraulic fluid is stored in while it is not being cycled through the system.
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Pump, Hydraulic component
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the pump pumps fluid through the system. It lies between the reserve tank and the accumulator.
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4 Components of the refrigeration system
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1. evaporator
2. compressor 3. condenser 4. Thermostatic expansion valve |
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What occurs in the chiller/evaporator of a refrigeration/AC system?
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Refrigerant flows from the chiller as a low pressure liquid/vapor mix which turns into a superheated vapor (generation).
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What occurs in the compressor of a refrigeration/AC system?
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In the compressor, it is compressed to a high pressure superheated vapor (compression).
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What occurs in the condenser of a refrigeration/AC system?
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In the condenser, sea water is cycled through it to remove heat and change it to a supercooled liquid (condensation).
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What occurs in the TXV of a refrigeration/AC system?
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In the TXV, refrigerant is expanded rapidly (cooling it) and then sent to the chiller (expansion). The TXV controls the flow of refrigerant, and therefore the temperature of the system.
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The TXV controls the flow of refrigerant, and therefore the _________ fo the system.
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temperature
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What are the two refrigerant health hazards?
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1. Phosgene gas hazard
2. Asphyxiation hazard in non-ventilated spaces |
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How is phosgene gas created?
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When refrigerant is exposed to high temperatures
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What are the 3 components of Electronic Warfare?
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Electronic support
Electronic attack Electronic protect |
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Electronic support
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actions taken to search for, intercept, identifty, locate, and exploit enemy electrnoic emision in order to conduct effective threat detection, indentification, warning, avoidance, targeting, and determination of intent.
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Electronic attack
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is an offensive use of the electronic magetic specturm by directed energy, deception, missiles to prevent or reduce the enemy's electromagnetic spectrum use for command and control, weapons employment, and communication.
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Electronic protection
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The protection of friendly combat capability against undersireable effect of friendly or enemy employment of EW.
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Wide spectrum surveillance
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can survey a broad range of frequencies
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Wide dynamic range
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can detect very strong and very weak signals
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unwanted signal rejection
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can filter out background noise
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angle-of-arrival measurement
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the ability to gauge the angle the signal is coming from
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signal analysis capability
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the ability to ID the platform that is producing the signal
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Display
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audio, lights, screens, etc that display signal data
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What are the 4 classes of electronic attack?
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Jamming
Expendable decoys radar-absorbent material anti-radiation weapons |
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Denial Jamming
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mask or hide real targets by cluttering the enemy receiver's radar
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3 Types of denial jamming
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Spot Jamming
Barrage Jamming Sweep Jamming |
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Advantage of denial jamming
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the jamming signal only has to travel in one direction, half the distance of the original radar signal which has to echo back.
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Spot jamming
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all power output of jammer is concentrated on a narrow band of frequencies
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Barrage Jamming
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uses amplitude modulated signals to spread energy over a bandwidth wider than that of the radar signal (10% of center frequency)
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Sweep jamming
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uses frequency modulated signals swept back and forth over a very wide bandwidth
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Deception jamming
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misleads enemy radar by providing it false target information. Commonly employed via repeaters and transponders. Also referred to as repeater jamming.
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2 types of deception jamming
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Range deception
angle deception |
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Range Deception
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the recieved signal is received, delayed, amplified, modulated, and retransmitted back to the victim radar.
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Angle Deception
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Take advantage of the side-lobes of radars or use timed signals against conical scan radars.
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Repeaters used for in EA
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create false echo by delaying received radar signals and retransmitting at later time in teh side lobe of a radar.
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Transponders used for in EA
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Create false signal by playing back a stored replica of the radar signal in the side lobe of a radar.
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Power, EP radar design
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fundamental parameter, outcome going to stronger, more powerful opponent
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Frequency, EP radar design
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change frequency within one pulse repetition time automatically or manually
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Pulse repetition frequency (PRF), EP radar design
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high PRF more resistant because average power is higher
changing PRF in random fashion |
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Pulse width, EP radar design
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increase in pulse width will increase average power
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Anetnna design, EP radar design
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low side lobes levels
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Scan pattern, EP radar design
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active tracking phased-array radar is EA resistant
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Emission Control (EMCON)
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A tiered system of managing a vessels emission of EM energy.
Alpha - Delta Alpha - silent Delta - essentials only Opterator Training - Training radar operators how to spot and counter jamming. |
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Explosive
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A material that can undergo a very rapid, self propagating decomposition, resulting in:
Formation of stable materials and gases Liberation of heat Development of sudden pressure effect through the action of heat. |
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Explosive yield
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Standard measure of strength for explosives, measured in weight of TNT; the amout of TNT to produce an equivalent blast as that of the explosive itself.
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Hygroscopicity
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Measure of moisture absorbing capability (minimal amout desired).
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Brisance
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Shattering effect (fragmenting rounds). French for breakable.
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Low explosives
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normally employed as propellants
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High explosives
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Primary - Extremely sensitive to impact, friction and heat
Secondary - Less sensitive (may burn in small, unconfined quantities; otherwise will detonate.) |
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Main components of a high explove train
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Detonator
Booster Main charge |
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Isotropic propagation
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blast is uniform in all directions
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Non-isotropic propagation
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directed blast, not uniform in every direction
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Blast warheads
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Designed to achieve best results from blast. Initial blast produces heat and overpressure.
Think pressure change Followed by a suction or underpressure - push/pull causes the intended target to explode from the pressure differential. |
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Fragmentation Warheads
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Blast energy is translated to the fragments of teh weapons casing. Approximately 30% of energy used to fragment the warhead.
Fragments proplelled at very high velocities, overtaking shock wave. Exceeds the radius of a blast weapon. Allows for greater inaccuracies in weapon use. |
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Conical Charge Warhead
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Weapon impacts target, fuze detonates main charge from the rear. Detonation wave sweeps forward and collapses the apex of metal cone liner.
Collapse results in the ejection of hih velocity molten jet. Pressure of jet is much greater than the armor yield strength. The jet is followed by a slug. The jet liquefies some armor (spalling). |
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Continuous Rod Warhead
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Used to damage aircraft in the event of a near miss
Series of rods connected and folded so that the series expands circularly. Doesn't produce as much destructive energy as the average fragmentation weapon. |
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Mach effect
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A third wave resulting from the reflected wave overtaking the original shock wave.
Can increase a blast weapon's effectiveness/radius range. |
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Triple point
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Where the three waves combine.
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Storage, launching system
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Safe and readily accessible until needed.
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Transfer, launching system
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move from storage to launcher and back
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Loading, launching system
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Placed into ready to fire position
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Control, launching system
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Direct and point launcher and Provide Weapons Orders
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3 Types of launchers
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Gravity
Impulse Rail |
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2 Types of impulse launchers
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Gun-Type Launcher
Ejector Launchers |
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Gun-Type Launcher
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Uses propellant powder to launch weapn or projectile
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Ejector Launcher
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Tube launchers i.e. torpedo. Uses compressed air or high pressure gas to launch weapon. Main purpose is to ensure tha the weapon safely clears the delivery vehicle.
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Rail type of launcher
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Weapon is launched from a ramp or rail
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Explosive propellant rain, main component
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Primer
Igniter Propellant Powder |
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How does the explosive propellant train function?
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Primer normally ignited by blows from a firing pin. An igniter is used to start the burning of the propellant powder. Propellant powder burns and produces the gases.
Similar to the high explosive train but with low explosives. |
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Liquid propellants
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More powerful than solid fuels
High volatility Can't be stored for long periods |
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Solid propellants
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Hydrocarbon and oxidizer combined to produce desired chemical potential
More stable for storage |
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3 types of Propellant Burning Rates
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Digressive
Neutral Progressive |
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Digressive burning rate
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As it burns, the burning surface area decreases
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Neutral burning rates
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The burning surface area remains constant
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Progressive Burning Rates
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Burning surface area increase as it burns
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Effect of burning rates on barrel length
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Digressive powders are used in weapons with short barrels and increasingly progressive-type powders are used in long barrels. This is so that in guns with long barrels, the propellant can burn and produce gases for a longer period of time (with the projectile still in the barrel) to propel it further. With a short weapon, this is unnecessary.
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Recoil
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The rearward movement of the gun and connected parts during and after firing.
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Counter Recoil
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After recoil, the gun and connected parts return to the in-battery, or firing, position
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3 types Recoil systems
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Recoil/Counter Recoil system
Muzzle Brake Soft Recoil system |
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Recoil/counter recoil system
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The gun is placed on a large spring or shock which absorbs some fo the gun's recoil.
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Muzzle Brake
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High velocity gases following the projectile are deflected rearward and sideways by baffles at the end of the barrel.
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Soft Recoil system
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The gun is placed on a spring or shock that is stretched out prior to firing, shortening the recoil time and force.
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3 types of reaction type launchers
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Rail
Zero Length Canister |
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Rail
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Makes use of rails, tubes, long ramps to provide a constraint to the weapon while it is moving along the launcher rail, and thus provides a considerable amount of flight control
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Zero Length
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Any rail launcher where the weapon travels fewer than 8 cm before release
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Canister
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Launch rail/tube and storage container in one
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How does a rocket motor function
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Burning propellant along the inside of the casing exerts pressure in all directions at once, until a nozzle is fitted at one end.
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Caliber (in the Navy)
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Barrel Length / Diameter
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What are the 3 main components in a turbojet, turbo fan, and turboprop engine?
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Compressor
Combustion chamber Turbine |
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How does a RAM jet work?
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makes thrust with pressure differentials;
it has no moving parts |
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How does a SCRAM jet work?
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Same principles at a RAM jet (uses pressure differentials; has no moving parts) but sucks air through at supersonic (not subsonic) speeds.
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5 Componenets of basic missile architechture
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Guidance
Warhead Sustainer Control Booster |
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Function of the Safing and Arming Device
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The S and A device is a fuze componenet that isolates the detonator from the warhead booster charge until the weapon has been launched in the intended mode and is a safe distance from the launch vehicle. At the programmed point in the trajectory, the S and A device removes the physical barrer from the explosive train, allowing the detonator thereafter to initiate the warhead.
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Activation forces for a detonator
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Impact
Ambient pressure Time Acceleration Centrifugal |
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Function of the Target Detection Device
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Determines whether a target is close enough to be contained within the damge volume of the warhead. Once the target has been detected or 'sensed,' the detection and recognition device either sends, or predicts when to send, a fire signal to the detonator.
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Four basic TDDs
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Point detonating, Impac, or Contact
Ambient Timer/Command Proximity |
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Fuze
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Weapon subsystem which activates teh warhead mechanism in the vicinity of the target.
Keeps weapon safe Arms weapon Recognizes or detects target Initiates detonation of warhead Determines direction of detonation - special fuzes only |
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Fuze, Fire control architecture
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TDD (sensing)
Detonator S and A Explosive Output Lead Warhead |
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4 different types of proximity fuzes
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Electromagnetic
Electro-optical Magnetostatic Acoustic |
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Electromagnetic proximity fuze
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Activated by an EM signal that is trasmitted to the missile
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3 typres of EM proximity fuzes
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Active
Semi-active Passive |
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Active EM proximity fuze
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The missile transmits a radar beam to the target, recieves it back and tracks it.
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Semi-active EM proximity fuze
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Separate radar tracks target and sends signal to missile
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Passive EM proximity fuze
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The missile only listens for emission from the target
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How is the S and A device wired?
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In series, so that if one fails, the other cannot allow the weapon to go off.
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How are TDDs wired?
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In parallel, with multiple detonators so that if one fails, the other can still detonate the weapon.
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Factors that affect how a weapon must be fired at a stationary or moving target from a launcher that is stationary or moving in order to hit the target.
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Realive motion
Exterior ballistics |
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Relative motion, fire control problem
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The firing vessel, the target vessel or both vessels can be moving during firing.
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Exterior ballistics, fire control problem
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Once a shell is fired, anything physical forces that act on it during launch and flight affect its path.
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6 exterior ballistics
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Gravity
Drag Wind Drift Coriolis Effect Magnus effect |
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3 types of drag
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skin drag
shape drag wave drag |
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skin drag
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friction on outer surface, resultin gin heat
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Shape drag
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low pressure zone forms behind projectile due to flow of air
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Wave drag
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acousitic waves form as projectile moves through the air
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Gravity
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acts in a downward motion on any fired projectile
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Wind
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wind can move a projectile horizontally and can affect its range
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Drift
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Drift is caused by the rotation of a projectile. Drift results in a lateral displacement from original plane of fire (side to side motion).
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Coriolis Effect
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This is the affect of the Earth rotation under the projectile as it travels. Results in apparent right curve in the norther hemisphere, left in southern.
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Magnus Effect
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This is the effect of pressure differentials caused by the spinning movement of the projectile. The side of the projectile that is spinning the same direction as the wind "pulls" air with it. This increases the velocity of the air, resultin in a lower pressure area. An area of high pressure forms on the other side of the projectile. It will be pushed away from teh high pressure towards the low pressure area.
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Mount, basic gun definitions
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Fixates gun on ship's structure
houses recoil/counter recoil system |
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Train, basic gun definitions
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Bearing position of the gun
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Elevation, basic gun definitions
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Upward angle from horizon
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Reason for rifling
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Rifling puts a spin on the bullet, which makes it travel in a straighter path.
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3 phases of missile launch
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Boost phase
Midcourse guidance phase Terminal phase |
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Boost phase
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Missile leaves teh launcher until Booster burned out
get the missile up to speed and places the missile at a high altitude to recive target info |
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Midcourse Guidance Phase
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Gets missile close to target; generally the longest phase
Gerneral corrections to course and altitude |
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Terminal phase
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Last phase; missile guidance is critical
Final correction, close the target, detonate warhead. |
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Homing logic (midcourse)
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The way in which a weapon closes the distance to the target
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2 types of homing logic
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Preset
Variable |
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Preset, homing logic
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path cannot be changed in midflight
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2 types of Preset, homing logic
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Constant
Programmed |
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Constant, preset, homing logic
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one phase - i.e. torpedo on a straight line to intercept surface target
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Programmed, preset, homing logic
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multiple phases - i.e. torpedo conducting search pattern until it acquires target
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Variable, Homing logic
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path altered according to conditions occurring during flight
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Pursuit, variable, homing logic
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continually fly toward and remain pointed at target. Most common application is against slow movign targets. Missile must have significant speed and maneuverability over target.
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Constant Bearing, Variable, Homing logic
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weapon is aimed at a point ahead of the target for interception. Suited for constant course and speed targets. Weapons speed is comparable to target.
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Line-of-sight (LOS), Variable, Homing logic
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weapon is guided so that it remains on the line joining the target and point of control. Launching platform assumes major burden of guidance.
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Proportional navigation, variable, Homing logic
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weapon guidance receiver measures rate of change of line-of-sight or the bearing drift and passes information to computer. Computer generates steering command to auto pilot.
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5 types of self contained guidance
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Navigational
Inertial Celestial Terrestrial GPS |
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Inertial, Self Contained Guidance system
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Uses accelerometers to sense weapon's movement and make adjustments to maintain flight path
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Celestrial, Self Contained guidance
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Weapon course is adjusted by reference to fixed stars.
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Terrestrial, Self contained Guidance
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Compares actual terrain with expected and adjusts flight path
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GPS, Self contained Guidance
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3 satellites to fix position, 1 satellite for time
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Detect to Engage sequence
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1. Detection and identification
2. Localize 3. Track 4. Weapon selection 5. Engage target 6. Battle damage assessment |
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Detection and identification, Detect to Engage sequence
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Electronic Support - matches emitter to library and provides bearing of incoming threat
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Localize, Detect to Engage sequence
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Combining information from long range air serach radar and ES sensors, the threat's bearing and range is determined.
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Track, Detect to Engage sequence
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Threat is detected by three dimentional search and track radar. Contacts bearing, range, altitude are precisely determined to give an accurate course and speed.
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Engage target,
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Missile enters terminal phase and proximity fuze is activated
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Battle damage assessment, Detect to Engage sequence
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Continue to track target to confirm kill.
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