Unit Specific

Avionics / Electrical  

203.1.1 state the purpose of the following communications equipment 

1.Intercommunications System (ICS)-AN/AIC-22, is installed to provide intercommunication functions for crewmembers. A pilot, co-pilot 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, co-pilot, and TACCO, and NAV/COMM. Audio monitor circuit is provided for special purpose equipment. Twelve (12) headsets are provided: one for each crew station, the ordnance station, and the nose wheel well. 

2. Ultra High Frequency (UHF)-two identical ARC-143UHF 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 stations and the flight stations. The UHF-1 control box is mounted in the flight station. It can be utilized for plain voice, cipher voice (VINSON) and 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 the aircraft incorporated 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 bands, and tactical military units in the low VHF-FM bands. The control panel is located in the flight station on the co-pilot side of the center control pedestal. The radio utilized for plain voice communication only. 

4. High Frequency (HF)-two ARC-161 HF receiver / Transmitters are installed in P-3C Aircraft. These identical radios are capable of transmitting in the range of 2 to 29.9999 MHz. Both HF control boxes are mounted at the NAV/COMM station. Operations 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 HF's 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 System (INS)-An automatic aid to navigation that is independent of outside references. An INS is a portion of the tactical system that provides accurate velocity, attitude, and heading 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 latitude, longitude, or altitude involves a change in its speed or direction of motion. The inertia's extremely sensitive accelerometer resists these changes. 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 updates 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 gyro-stabilized for pitch, roll, and yaw. 

3. Global Positioning System (GPS)- the AN/ANR-151 (V) GPS is a world wide, 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 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 bearing to a selected sonbuoy 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 dual-bus architecture to provide high processing performance, configuration options and growth capabilities. It operates with peripheral devices (such as a magnetic tape unit, printers, 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 form 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 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 lines of force of the Earth.

7. Electronic Support Countermeasures (ESM)- the ALR-66 gathers intelligence from the enemy's electronic devices and make them 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 form a heat source. The IRDS display targets images in a television-type display on a CRT located at the non-acoustic operator station. IRDS is a passive system, operating in the 8-14 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 Electro-Optical (EOA)- an advanced 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 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 operations, the generator maintains the battery in a charged state.

2.Main Alternating Current-the P-3 utilizes AC as the primary electrical powers source. The AC power requirements are supplied by four interchangeable brush less generator that supplies 120 Volts; three phase power at 400 HZ. 

2. Transformer Rectifier- the heart of the DC power system is the transformer rectifier unit. Transformer-rectifiers 1&2 receive AC power directly from the main AC buses A and B, respectively. They in turn rectify the AC input to a 28-volt DC output fro use at the main DC bus. Transformer-rectifier 3 receives its power input from the NEAC bus and routes its 28VDC output to the MEDC.

4.Spervisory Panel-each generator has an associated supervisory panel located in the main electrical load center. Each contains its respective GCR, ACR, and voltage regulators. The panel provides over-voltage, under voltage, 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 non-essential equipment through the aircraft. The monitor AC bus currently has no load attached to it. When used, it provides power to non-essential equipment only. With both generators operating, AC essential buses # 1 & #2 and the 115 Volts AC instrument bus power safety-of- flight equipment. The main generators normally supply power to these two buses, but they also tie to the emergency generators when it is in operation. A step down transformer supplies 26 VAC fro the 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 system 

• Strobe lights-two high intensity strobe lights are installed along side the centerline on the aft fuselage, top and bottom. They provide anti-collision warning to other aircraft.
• 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 fro identifying the heading of approaching aircraft in flight.
• Landing Lights-installed at the trailing edge of the port and starboard wings, between the inboard and outboard nacelles. These lights are used during take off, approach, and landings.
• Tail Lights-the tail position lights are located on the bottom of the aft fuselage and the top forward section of the MAD boom.
• Taxi Lights-installed on the left and right sides of the nose gear struts. These lights are used during taxiing