Principals of Undersea Sound
Describe the tactical releavance differences between active and passive SONAR.
Passive SONAR provides bearing to target, but not range.
What is the effect of the Earth's rotation on a projectile?
Coriolis
Name two of the four briefed considerations when designing a launching system.
compatibility, reliability, speed, safety
Give an example of a time/command fuze.
Illumination, hand grenade, air burst
(BLANK) is when a wave changes direction as they pass from one medium to another.
Refraction
What factors determine the speed of sound in water?
Temperature, Pressure, Salinity.
What causes the projectile to spin as it travels down the barrel?
Describe difference in recoil/counter-recoil and soft recoil systems.
Soft recoil systems move forward out of battery prior to weapons release. Recoil/counter-recoil systems fire from battery position.
What does a hydrostatic proximity Target Detection Device sense?
Pressure Variation
What is the Detect to Engage Sequence?
F2T2EA
What Law tells us sound waves change direction when passing through different mediums. This is known as what?
Snell's Law, Refraction
Name all five factors of exterior ballistics.
Gravity, Drag, Wind, Drift, Coriolis
Name three types of propulsion.
Gravity, Impulse, Reaction
Name the three phases of missile guidance.
Boost, Midcourse, Terminal
What is the only case where a servo tracking system's error would reach zero?
Target not moving
Name 3 of the 6 sound propagation paths.
Direct Path, Half Channel, Surface Duct, Sound Channel, Convergence Zone, Bottom Bounce.
Name the three propellant types.
Degressive, Neutral, Progressive
This recoil management system pushes the systems gas against baffles parallel to the line of fire.
muzzle brake
name the four types of guidance systems.
Control, Homing, Track Via Missile (TVM), Self Contained.
(BLANK) is defined as the number of occurrences of a repeating event per unit of time.
Frequency
What does VDS stand for? And what does it do?
Variable Depth SONAR. Allows towed array to dive below sonic layer depth.
Name all five factors of Interior Ballistics that control Muzzle Velocity
Projectile weight
gas pressure
barrel length
friction
barrel/propellant/projectile temperature
This missile control configuration puts the controls forward and has a delayed response.
Canard
What does parallel reliability ensure?
Function (detonation reliability)
What term is used to describe frequency change due to relative motion determining approaching or retreating targets?
Doppler (Effect)