AS 08 - AN / APS 504 (V) 3 CT 142 Radar Flashcards
Review Questions
What are the distance rules for avoiding storm clouds?
5 NM below freezing level
10 NM above freezing level
20 NM when flying above 30 000’
Review Questions
What do scalloped or rapidly changing edges indicate on a weather radar return?
Developing storm, should be avoided by greater distances.
The ANAPS 504 Radar system is a multi-mode unit. What are it’s applciations?
SAR, surveillance, nav and WX detection.
What are the AN/APS 504 components?
SPCU Power Supply Antenna Waveguide Pressurization System NTSC LCD ATS Controls Receiver/ Transmitter Pilot's Control Panel RRIU
What is the Radar Hazard Area for exposed personnel and refueling vehicles, 360° around the AC, even in DUMMY Load?
100 ft
When does DUMMY Load have to be on at all times?
When the AC is on the ground.
Describe the Antenna component specs.
14x42’’ flat plate planar array
360° rotation capability
Manual tilt control of +/- 16°
Describe the Waveguide Pressurization System
Pressurizes the R/T and waveguide with nitrogen to prevent condensation and arcing at high altitude.
Located in the nose
System comprised of high-pressure nitrogen bottle, a large gauge and a regulator.
Radar Location & Power Supply
- How many inverters provide power for the RADAR only?
- Where is the radar power switch located?
- What does the radar power switch allow?
There are three separate inverters for the radar located in the AC’s nose
The radar power switch is located on the co-pilot’s side console
The inverter power switch allows the three radar inverters to power up and supply the radar system with 115V AC
Describe the Radar/ Transmitter components
- Explain the process
- Frequency
- Signal
The transmitter generates a RF signal and the receiver processes the returned RF signal for conversion to a video signal.
The R/T isolates and monitors faults and key radar parameters.
The transmitter frequency is 9310 to 3975 MHz
80 KW minimum peak signal, 100KW is typical
R/T is located in the nose
Pitch, roll and heading from IRU are sent to the antenna to ensure what?
The antenna rotational plane remains stationary with changes in AC attitude, up to 20° from horizontal (think a chicken’s head)
Describe the Navigation Training System Computer (NTSC)
The NTSC is the heart of the NTS, it interfaces with the radar via RRIU and it processes all video data
Describe the Remote Radar Interface Unit (RRIU)
- Interfaces with
- CDU and PCU significance
The RRIU interfaces with the ATS computer with the search radar via a full duplex RS-422 data link
This interface allows the radar to be controlled by operator inputs through emulated CDU
Also interfaces the radar with the PCU, allowing pilot-control of the radar when the NTS is not selected
Describe the Synchronizer Processor Converter Unit (SPCU)
- Timing
- Processing
- Supplies
- Receives
- Circuitry
Provides overall radar system timing and control, video/signal processing and radar scan conversion.
Supplies the transmitter with command and control signals
Receives radar video inputs from the receiver
Contains control/ sync circuitry, video signal processing circuitry and scan converter circuitry
What does the Display provide?
High resolution, 3-colour Liquid Crystal Display (LCD) of enroute weather, ground mapping and navigation information within the antenna scan area.
What does the Display receive from the: R/T Antenna PCU NTS
R/T: Video data & a trigger pulse
Antenna: Azimuth synchro data
PCU: Control signals
NTS: Emulated CDU
What is the only control provided on the indicator?
Brightness
What is the keypad and trackball used for on the display?
Used to input information into the computer
Fun Fact:
Sliced bread was first manufactured by machine and sold in the 1920s by the Chillicothe Baking Company in Missouri.
Carry on with your studies soldier
What does the Radar display present the user?
Scan return
AC’s True heading & local variation
Current time in UTC
Bearing from AC to cursor location & distance from the AC to the cursor location
The hook’s bearing in relation to the AC & hooks distance to the AC
How many ranges are available for radar selection? What are they?
8 in total
All ranges in NM
3 6 12 25 50 NP 50 WP 100 200
Which Range Selections have a narrow pulse and high PRF?
3, 6, 12, 25 and 50NM narrow pulse.
Which Range Selections are wide pulse?
50 (WP), 100 and 200NM
A low PRF and and wide pulse are better suited for what range?
Long range detection
A high PRF and narrow pulse are better suited for what range targets?
Closer range
True or false
The radar RPM is determined by range selection.
True
Fill in the following Antenna RPMs for the corresponding Ranges
3NM to 50NM NP
50NM WP to 100NM
200NM
3NM to 50NM NP = 30 RPM
50NM WP to 100NM = 12 RPM
200NM = 7.5 RPM
What do the following inputs provide/ allow/ receive?
IRU
Fix Button & Keyboard
NTS Computer
IRU: Provides heading, pitch, roll information for antenna stabilization (chicken head)
Fix Button & Keyboard: Allows inputs of target coordinates and altitude
NTS Computer: Receives video input from the radar
WRT Outputs, control signals from the CDU go to the radar via the _____.
RRIU
WRT Outputs, video display, radar range & mode and ____ ________ go to the LCD (operator display) via the what?
Fix information
Via the NTS computer
WRT Outputs, cursor position goes to the DID via the what?
NTSC
Fault Response - Radar Hot indicates what and require what steps to be taken?
Indicates the SPCU is overheating
Steps to be taken:
Radar system shut off via the radar power switch, located on co-pilots side panel
Open the computer cabinet and inspect for smoke or fire.
Review Questions
What is the difference between 50NP and 50WP modes?
50NM NP - High PRF for target definition and good target detection at close range by providing more target returns per scan.
50NM WP - Low PRF keeps the average power high, provides the time needed to receive returns at longer ranges, improving long range target detection capabilities
Review Questions
The Antenna is stabilized to what horizontal limits?
20° from the horizontal
Review Questions
What does “HOT” indication mean when it is displayed in the Control area?
What should be done to prevent further damage to the system?
SPCU is over heating
Turn it off via the radar power switch
Inspect the computer cabinet and inspect for smoke or fire
