Radar

Question 1

What is the difference between the primary radar and secondary system on a surveillance radar?

Answer 1

Primary radar uses
reflected radio signals. The secondary
system transmits a radio signal which
initiates a reply of information from an
aircraft transponder.

Question 2

What are the two types of Surveillance Radar?

Answer 2

ARSR (Air Route Surveillance Radar - Long Range) and ASR (Airport Surveillance Radar - Short Range)

Question 3

What is a PAR?

Answer 3

Another type of RADAR used by ATC is Precision Approach Radar (PAR). PARs are very accurate short range radars designated to enable controllers to provide precise range, azimuth, and elevation to aircraft on final approach.

Question 4

What time of information can be displayed from the secondary radar return (transponder)?

Answer 4

Type, ID, Speed, Altitude

Question 5

What are the two most important atmospheric conditions to a flight inspector with respect to Radar inspection?

Answer 5

Precipitation and Temperature inversions - They can adversely affect an inspection by cluttering the scope

Question 6

What is the range of a typical ASR?

Answer 6

60 NM and 10,000 feet

Question 7

Which ASRs do not require periodic flight inspection?

Answer 7

ASR’s without surveillance approaches or
Minimum Safe Altitude Warning (MSAW)
functions do not require a periodic flight
inspection.

Question 8

Which secondary radar function requires a flight inspection aircraft during commissioning?

Answer 8

ATCRBS (Air Traffic Control Radar Beacon System)Power Optimization

Question 9

What kind of guidance is a PAR used for?

Answer 9

Final Approach Guidance ONLY (10-20 NM range)

Question 10

What is the purpose of Linear and Circular polarization controls?

Answer 10

Circular polarization significantly reduces the intensity of precipitation echoes. This allows controllers to see aircraft echoes even when the aircraft are in heavy
rain or when heavy rain is between the radar and the aircraft.

Question 11

During a radar inspection, checks are typically done in what configuration?

Answer 11

Most checks are done with the radar in a “worst
case” configuration. This means that any operator aids that detract from optimum performance, such as CP, must be in use and those that enhance performance (such as video integrator) are turned off except for brief spot checks.

Question 12

What is the Moving Target Indicator (MTI)?

Answer 12

It allows the radar to eliminate targets that are not moving such as terrain or structures. If MTI is required for any part of the facility operation, it does not mean the facility should be restricted. However, ASR approaches which require MTI are not authorized when MTI is inop.

Question 13

How do we inspect ATCRBS Power optimization?

Answer 13

ATCRBS Power Optimization is done to adjust the power of the transmitted secondary signal to best meet operational needs. Too much power causes problems with aircraft transponders, false or distorted
echoes, and other odd-looking returns. The aircraft flies an arc in an area chosen by maintenance at the
maximum range of the radar. (10,000’for ASR and 30,000 for ARSR) NOTE: If the beacon power is adjusted during this check, any checks that were previously accomplished must be done again.

Question 14

What does the PRM (Precision Runway Monitoring)/ FMA (Final Monitor Aid) system do?

Answer 14

Through secondary radar, it allows ATC to control multiple aircraft on simultaneous final approaches to parallel runways, significantly increasing the landing rate.

Question 15

What is MSAW?

Answer 15

Minimum Safe Altitude Warning System - alerts controllers when an aircraft descends to an unsafe altitude.

Question 16

Where is guidance for inspection of PRM/FMA systems?

Answer 16

8200.39

Question 17

How do we inspect MSAW components: GTM and APM?

Answer 17

For the General Terrain Monitor (GTM), descend to or below the minimum altitude and verify that the
controller gets an alarm. For the Approach Path Monitor (APM), descend below the normal glide path into the monitored area and verify the controller gets an alarm. APM checks are accomplished by request only.

Question 18

How do we evaluate ASRs?

Answer 18

The pilot follows controller instructions and determines if the aircraft is in tolerance at the Missed
Approach Point (500’ from the runway edge for straight-in approaches).

Question 19

What to A and B cursor refer to?

Answer 19

A refers to normal glidepath and B refers to the Lower Safe Limit, below the glidepath.

Question 20

Where is the alignment tolerance applied for a PAR?

Answer 20

Ideally, the entire inbound course should be aligned with the runway centerline, but the tolerance is applied only at the runway threshold.

Question 21

How is usable distance measured on a PAR?

Answer 21

Proceed inbound from the coverage limit during the Course Alignment check, have the controller give the mileage when the aircraft is first displayed on the scope.