Radar And RADALT Flashcards
What does radar stand for?
RAdio Detection And Ranging
How long does it take for a radar pulse to travel 1 mm?
6.18 micro seconds
What is a radar mile?
The time that it takes an RF signal to travel one nm and return from a reflecting object.
What is minimum range?
The shortest distance to an object a radar can detect.
What is a duplexer?
It alternately switches the antenna connection between tx and rx.
What does maximum range depend on?
Peak power of transmitted RF pulse, Piles repetition frequency (prf), receiver sensitivity, and RF pulse frequency.
What is the interface-synchronizer unit?
The “heartbeat” of the radar system; supplies timing and synch signals fro the transmitter, receiver, antenna, indicator and other components.
Processes raw video from the receiver into composite video for the indicator.
What is the purpose of the radar receiver/transmitter?
Generate short electromagnetic pulses at high frequency and high power. Converts weak received signals into raw video
What is the purpose of the RADAR system?
To provide a scaled display of surface mapping, target detection and weather avoidance.
What is the purpose of the range selector?
Provides the pilot with different range selections for the indicator.
What is the STBY mode of operation of radar?
A warm-up period. Energizes the system but does not allow radar transmissions.
Selected during taxi and ground operations
What are the different search modes go the RADAR system?
SRCH1- searching for targets in high sea states @ 10 mm or less
Scan integration is available
SRCH2- low sea states or precision ground mapping.
SRCH3- maximum clutter returns for mapping oil slick areas
What is the weather mode of the radar system?
Detects presence of weather patterns. Uses ISO-echo contouring to distinguish storm centers or areas of most intense weather activity.
What is the weather alert mode?
Additional weather information, will flash the areas of dense weather cells
What are the 2 types of RADALT?
Radar altimeters And Radio altimeters
What is the range of the radar altimeter?
0-5000ft
What is the frequency of the radar altimeter pulse?
4300MHz
What is the accuracy rage of a radio altimeter?
0-2500 ft
How does a radio altimeter work?
It sends out a frequency modulated continuous wave signal varying from 4350MHz- 4250 MHz. The RADALT then measures rate of change and fm ranging.
What are the steps for completing a self test on the RADALT system?
1) apply aircraft power
2) ensure circuit breaker is depressed
3) allow for warm up time
4) rotate decision height to correct setting.
5) press and hold “self test”
6) observer
7) let go of the self test button
What is normal track?
Mode of operation that occurs web power is applied to the RADALT system.
It provides accurate height indication, decision height, aural warning, no track, and system failure conditions
What is the decision height?
Height specified which the aircraft shall not descend below during flight.
What is no track?
When the aircraft exceeds the RADALT limits
What are some possibilities when you have a RADALT system failure?
The altitude pointer may archer, park, or park behind the mask. A failure flag and / or failure audible warning will alert the pilot
What is the purpose of the receiver/transmitter for the RADALT system?
Transmit, process received signal, tracking RADALT RF, generates necessary outputs for the height indicator, valid signal flags, decision height lamp, and audio warning.
