NRTC 14340 UNDERSEA WARFARE (2023/2024) RATED A+

NRTC 14340 UNDERSEA WARFARE (2023/2024) RATED A+ the acronym sonar is derived from what words sounds, navigation, and ranging a sonar transducer can be compared to which of the following items microphone signal strength lost as sound waves travel through water is known by what term transmission loss which of the following sea states causes the greatest amount of absorption whitecap waves sound waves in seawater travel how many times faster than sound waves in air 2 which of the following sea floor surfaces has the least amount of signal loss smooth and hard multiple reflection of a sound wave is referred to by what term reverberating which of the following statements best describes the effect of divergence on sound waves the wave spreads out and becomes weaker with distance what is the most important factor affecting the speed of a sound wave in seawater temperature an increase in the salinity of seawater has what effect on the sound wave speed increases according to the Doppler effect, when the source of a sound wave is moving away from the receiver, what apparent change in the sound wave takes place the frequency decreases what are the three most common propagation paths for sound waves direct, bottom bounce, and convergence what is the minimum number of sonobuoys normally deployed during a USW mission 3 acoustic data received from a sonobuoy is transmitted to the sonobuoy receiver using what frequency and what type of modulation VHF, FM sonobuoys that transmit an acoustic pulse and detect a resulting echo are classified as what type of sonobuoy active what are the three methods of deploying a sonobuoy pneumatic, free-fall, and cartridge sonobuoy descent-retarding devices are necessary for what reason to reduce water entry shock how are sonobuoys activated saltwater battery activation what happens to the sonouoy after the battery dies it sinks to the bottom sonobuoys equipped with an EFS system have what capability selectable channel, life and depth settings a LOFAR sonobuoy uses what type of hydrophone omnidirectional under most situations, what type of sonobuoy is best for initial detection LOFAR what information can a DIFAR sonobuoy provide that a LOFAR sonobuoy cannot submarine bearing Which of the following sonobuoys is designed for long-range submarine detection in deep water VLAD DICASS sonobuoys operate on the same principle as what other electronic system radar DICASS sonobuoys are commanded to ping by what source a UHF signal from the USW aircraft an EER sonobuoy is typically used in conjunction with what other sonobuoy for long range detection VLAD what are the two special-purpose sonobuoys BT and DLC what information does a BT sonobuoy provide water temperature versus depth the ARR-78 sonobuoy receiver is capable of simultananeous reception of up to what number of sonobuoys 20 the ARR-84 sonobuoy receiver is used in the SH-60 series helicopter for what reason accommodation of weight restrictions what component of the sonobuoy-based sonar system extracts acoustic target information from both active and passive sonobuoys spectrum analyzer the OTPI system works in conjunction with what other aircraft system DF the OTPI system provides what information to the USW pilot sonobuoy bearing with respect to aircraft heading dipping sonar systems use what type of sonar detection active only what distinct advantage does a dipping sonar have over a sonobuoy based system operator control of the search depth in addition to active and passive sonar modes, a dipping sonar provides what other information communications and water temperature the electrical interface between the sonar set units mounted in the helicopter and the submerged sonar transducer is provided by what component of the ASQ-13F dipping sonar set multiplexer what unit of the ASQ-13F converts sound energy to electrical signals transducer a submerged sonar transducer is used to transmit and receive voice signals to and from other USW helicopters, submarines, or similarly equipped surface ships during what ASQ-13F mode of operation UVC angles of change in the earth's natural magnetic field in the east-west direction is known by what term variation angle the maximum range at which a submarine may be detected depends on the intensity of its magnetic anomaly and what other factor the sensitivity of the detector if the detectable strength of a magnetic field source has a given value at a given distance and the distance is doubled, the detectable strength of the source at the increased distance will then be how much of its former value one-eigth any noise or disturbance originating in the aircraft or its equipment that could produce a signal on a MAD equipment recorder is known by what term magnetic noise maneuver noises caused by eddy current flow can be minimized by taking what action making slow aircraft maneuvers any magnetic field may be defined in terms of what number of axial coordinates 3 what is the purpose of magnetic compensation in USW aircraft to provide a magnetically clean environment compensation for an aircraft's dc magnetic field is accomplished by using how many electromagnetic loops 3 the natural spin axis wobble rate of a particular atom is referred to by what term larmor frequency what component or components of a helium magnetometer detect the energy level changes of the helium atoms and produces an electrical output infrared detector what are the main components of a basic MAD detecting set magnetic detector, amplifier-power supply, and detecting set control when maintenance is performed on or near the magnetometer head, what type of tools must be used nonferrous what is the approximate warm-up time for the AN/ASQ-81 MAD system 5 min what fault indicator on the MAD control box indicates an amplifier failure 2 what is the purpose of magnetic compensation to reduce the effects of unwanted magnetic disturbances what are the three magnetic fields relative to MAD compensation transverse, longitudinal, and vertical in practice, how many terms are needed to compensate any aircraft satisfactorily 9 the compensator group adapter (CGA) serves what purpose computerizes the compensation calculation what is the purpose of the submarine anomaly detector (SAD) system separates submarine anomalies from magnetic noise