Radar And RADALT

Question 1

What does radar stand for?

Answer 1

RAdio Detection And Ranging

Question 2

How long does it take for a radar pulse to travel 1 mm?

Answer 2

6.18 micro seconds

Question 3

What is a radar mile?

Answer 3

The time that it takes an RF signal to travel one nm and return from a reflecting object.

Question 4

What is minimum range?

Answer 4

The shortest distance to an object a radar can detect.

Question 5

What is a duplexer?

Answer 5

It alternately switches the antenna connection between tx and rx.

Question 6

What does maximum range depend on?

Answer 6

Peak power of transmitted RF pulse, Piles repetition frequency (prf), receiver sensitivity, and RF pulse frequency.

Question 7

What is the interface-synchronizer unit?

Answer 7

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.

Question 8

What is the purpose of the radar receiver/transmitter?

Answer 8

Generate short electromagnetic pulses at high frequency and high power. Converts weak received signals into raw video

Question 9

What is the purpose of the RADAR system?

Answer 9

To provide a scaled display of surface mapping, target detection and weather avoidance.

Question 10

What is the purpose of the range selector?

Answer 10

Provides the pilot with different range selections for the indicator.

Question 11

What is the STBY mode of operation of radar?

Answer 11

A warm-up period. Energizes the system but does not allow radar transmissions.

Selected during taxi and ground operations

Question 12

What are the different search modes go the RADAR system?

Answer 12

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

Question 13

What is the weather mode of the radar system?

Answer 13

Detects presence of weather patterns. Uses ISO-echo contouring to distinguish storm centers or areas of most intense weather activity.

Question 14

What is the weather alert mode?

Answer 14

Additional weather information, will flash the areas of dense weather cells

Question 15

What are the 2 types of RADALT?

Answer 15

Radar altimeters And Radio altimeters

Question 16

What is the range of the radar altimeter?

Answer 16

0-5000ft

Question 17

What is the frequency of the radar altimeter pulse?

Answer 17

4300MHz

Question 18

What is the accuracy rage of a radio altimeter?

Answer 18

0-2500 ft

Question 19

How does a radio altimeter work?

Answer 19

It sends out a frequency modulated continuous wave signal varying from 4350MHz- 4250 MHz. The RADALT then measures rate of change and fm ranging.

Question 20

What are the steps for completing a self test on the RADALT system?

Answer 20

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

Question 21

What is normal track?

Answer 21

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

Question 22

What is the decision height?

Answer 22

Height specified which the aircraft shall not descend below during flight.

Question 23

What is no track?

Answer 23

When the aircraft exceeds the RADALT limits

Question 24

What are some possibilities when you have a RADALT system failure?

Answer 24

The altitude pointer may archer, park, or park behind the mask. A failure flag and / or failure audible warning will alert the pilot

Question 25

What is the purpose of the receiver/transmitter for the RADALT system?

Answer 25

Transmit, process received signal, tracking RADALT RF, generates necessary outputs for the height indicator, valid signal flags, decision height lamp, and audio warning.