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203.1.1 State the purpose of the following communication equipment:

  1. Intercommunication System (ICS)- an ICS, AN/AIC-22, is installed to provide intercommunication functions for crewmembers. A pilot, copilot, and TACCO-operated public address (PA) system and radio receiving facilities are provided for each crew station. In addition, radio transmitting facilities are provided for the pilot, copilot, TACCO, and NAV/COMM. Audio monitor circuits are provided for special purpose equipment. Twelve headsets are provided: one for each crew station, the ordnance station, and the nose wheelwell.

  2. Ultra High Frequency (UHF)- two identical ARC-143 UHF transceivers are installed in the P-3C aircraft. These radios are functionally identical; however, they have different capabilities because of aircraft wiring differences between the NAV/COMM station and the flight station. The UHF-1 control box is mounted in the flight station. It can be utilized for plain voice, cipher voice (Vinson), and UHF-DF in conjunction with the ARA-50 amplifier and DF loop antenna. The UHF-2 control box is mounted at the NAV/COMM station and is capable of plain voice, cipher voice, teletype, data link, sonobuoy command, and IACS.
  3. Very High Frequency (VHF)- the ARC-182 VHF/UHF radio system is installed in ciarcraft incorporating AFC-485 to allow communication with civilian and military agencies in the VHF-AM and UHF bands, civilian maritime units in the high VHF-AM band, and tactical military units in the low VHF-FM band. The control panel is located in the flight station on the copilot side of the center control pedestal. The radio is utilized for plain voice communication only.
  4. High Frequency (HF)- two ARC-161 HF receiver/transmitters are installed in the P-3C aircraft. These radios are identical and capable of transmitting in the range of 2 to 29.9999 MHz. Both HF control boxes are mounted at the NAV/COMM station. Operation of the two radio sets are independent of each other. However, an interlock automatically grounds the unused radio when a mike is keyed on either HF. Both HFs are capable of plain voice, cipher voice, teletype, and data link.

203.1.2 State the purpose of the following navigation equipment:

  1. Inertial Navigation Systems (INS)- an automatic aid to navigation that is independent of outside references. An INS is a portion of the overall tactical system that provides accurate velocity, attitude, and heading data to a digital data processing system. This overall system permits accurate weapons delivery. To function properly, the system must be aligned with reference to initial conditions of altitude, latitude, and longitude. The aircraft gyros, accelerometers, synchros, servos, and computers continually monitor aircraft heading, attitude, and horizontal and vertical velocities. Any change in the aircraft’s latitude, longitude, or altitude involves a change in its speed or direction of motion. The inertia of extremely sensitive accelerometers resists these changes. This resistance is measured and recorded by the synchros, servos, and computers. The computers continually recalculate the movement of the aircraft based on the latest changes recorded by the accelerometers. The computers use these calculations to provide a constantly updated readout of the aircraft’s geographical position.

  2. Tactical Air Navigation (TACAN)- the Navy uses TACAN as the primary navigation aid for carrier-based aircraft. TACAN has integrated distance measuring equipment (DME). The size of the system allows it to be based aboard ship and gyrostabilized for pitch, roll, and yaw.
  3. Global Positioning System (GPS)- the AN/ARN-151 (V) GPS is a worldwide, all-weather positioning system that provides the NAV/COMM with a fixed position readout that is accurate to 5 to 8 meters when operated with proper AS/AS crypto installed. In addition to position information, the GPS provides a display of various navigational and tracking data.
  4. Automatic Direction Finder (ADF)- frequencies between 100 and 1750 kHz.

203.1.3 State the purpose of the following tactical mission equipment:

  1. On-Top Position Indicator (OTPI)- the OTPI receiver control panel, located on the center pedestal of the flight station, enables the OTPI receiver to provide bearings to a selected sonobuoy channel.

  2. Tactical computer- the CP-2044/ASQ-212 digital data computer is a real-time multipurpose digital computer. The central computer uses multiple processors and a dual-bus architecture to provide high processing performance, configuration options, and growth capabilities. It operates with peripheral devices (such as magnetic tape units, printers, and displays together with other input/output devices) in a primarily digital data system.
  3. Acoustic audio sensors- the ARR-72 sonobuoy receiver system consists of 31 fixed tuned receivers that receive RF inputs from two blade antennas.
  4. Radio Detection and Ranging (RADAR)- the APS-115 is a radio device used to detect objects at distances much greater than is visually possible. Detectable objects include aircraft, ships, land areas, clouds, and storms. In addition to detecting these objects, the radar shows their range and relative position.
  5. Identification Friend or Foe (IFF)- the APX-76 an electronic system that allows a friendly craft to identify itself automatically before approaching near enough to threaten the security of other naval units.

  6. Magnetic Anomaly Detector (MAD)- the ASQ-81 system is equipment that utilizes the principle that a metallic submarine disturbs the magnetic lines of force of the earth.

  7. Electronic Support Measures (ESM)- the ALR-66 gathers intelligence from the enemy’s electronic devices and make the devices ineffective. Electronic countermeasures consist of two general types of actions- passive and active. The ULQ-16 is a pulse analyzation system used in conjunction with the host system for determining parametric data.
  8. Infrared Detection System (IRDS)- the AAS-36 converts infrared radiation emanating from a heat source. The IRDS displays targets images in a television-type display on a CRT lacated at the nonacoustic operator station. IRDS is a passive system, operating in the 8 to 14 micron range.
  9. Inverse Synthetic Aperture Radar (ISAR)- the APS-137 radar is a processing system that generates true, recognizable, two-dimensional images of any selected ship target.

203.1.4 State the purpose of the following special mission equipment:

  1. AVX-1 Electro-Optical System (EOS)- an advances Electro-Optical (EO) imaging system that provides high-resolution photography and video.

  2. APG-66 RADAR- an airborne, multimode, digital, pulse doppler system designed to provide all weather detection of airborne and surface targets in low- and high-clutter environments.

203.1.5 State the function of the following equipment:

  1. Aircraft battery- provides a reserve source of electrical power for select electrical systems. During normal aircraft operation, the generator maintains the battery in a charged state.

  2. Main alternating current- the P-3 utilezed AC as the primary electrical power source. The AC power requirements are supplied by four interchangeable brushless generators that supply 120-volt, three-phase power at 400 Hz.
  3. Transformer Rectifier- the heart of the DC power system is the transformer rectifier unit. Transformer-rectifiers 1 and 2 receive AC power directly from main AC buses A and B, respectively. They in turn rectify the AC input to a 28-volt DC output for use at the main DC bus. Transformer-rectifier 3 receives its AC power input from the NEAC bus and routes its 28-VDC output to the MEDC bus.
  4. Supervisory panel- each generator has an associated supervisory panel located in the main electrical load center. Each contains its respective GCR, ACR, and voltage regulator. The panels provide overvoltage, undervoltage, off-frequency, and feeder fault protection to their respective generators.

203.1.6 State the purpose of the Multiple Aircraft Electrical Bus system.

The left and right main ac buses provide power to nonessential equipment throughout the aircraft. The monitor ac bus currently has no load attached to it. When used, it provides power to nonessential equipment only. With both generators operating, ac essential buses number 1 and number 2 and the 115-volt ac instrument bus powers safety-of-flight equipment. The main generators normally supply power to these two buses, but they also tie-in to the emergency generator when it is in operation. A step-down transformer supplies 26 Vac for instruments and navigation systems. The output of the transformer also provides power to safety-of-flight equipment.

203.1.7 State the purpose of the following aircraft exterior lighting systems:

  1. Strobe lights- two high-intensity strobe lights are installed along the centerline on the aft fuselage, top and bottom, to provide anticollision warning to other aircraft.

  2. Wing tip lights- wing position lights are installed in the tips of each wing. The port wing tip light is red and the starboard wing tip light is green. The different color wing tips are used for identifying the heading of approaching aircraft in flight.
  3. Tail lights- the tail position lights are located on the bottom of the aft fuselage and the top forward section of the MAD boom.
  4. Landing lights- installed at the trailing edge of the port and starboard wings, between the inboard and outboard nacelles. These lights are used during takeoff, approach, and landings.
  5. Taxi lights- installed on the left and right sides of the nosegear strut. These lights are used during taxiing.