A03: Radar Quiz

Q1. What happens to the DME distance reading when the aircraft is directly above the ground station?

It shows the aircraft’s height in nautical miles

It shows zero distance

It shows an error and no reading

Correct answer is – It shows the aircraft’s height in nautical miles

Q2. How does secondary radar differ from primary radar?

Secondary radar transmits and receives on the same frequency

Secondary radar receives a reply from the target’s transponder

Secondary radar uses reflected pulses only

Correct answer is – Secondary radar receives a reply from the target’s transponder

Q3. What does RADAR stand for?

Radio Detection And Ranging

Radio Direction And Reception

Radio Distance And Refracting

Correct answer is A – Radio Detection And Ranging

Q4. Reliable DME signals can be received up to what range (line-of-sight altitude)?

199 NM

50 NM

100 NM

Correct answer is – 199 NM

Q5. What does the acronym RHO-THETA represent in navigation?

Distance and bearing

Latitude and longitude

Speed and altitude

Correct answer is – Distance and bearing

Q6. DME full form is?

Distance Maintaining Equipment

Distance measuring equipment

Digital Measuring Equipment

Correct answer is – Distance measuring equipment

Q7. What is the typical frequency range used by DME?

960–1215 MHz

118–137 MHz

225–400 MHz

Correct answer is – 960–1215 MHz

Q8. What is the primary function of Surface Movement Radar (SMR) in air traffic control?

Measuring the speed of airplanes during takeoff

Detecting and tracking aircraft and vehicles on airport runways and taxiways

Tracking aircraft in flight at long range

Correct answer is B – Detecting and tracking aircraft and vehicles on airport runways and taxiways

Q9. How long is the fixed beacon delay accounted for in DME calculations?

25 microseconds

50 microseconds

100 microseconds

Correct answer is – 50 microseconds

Q10. What is the main purpose of Radar?

To detect objects and measure their distance

To send radio messages

To amplify signals

Correct answer is B – To detect objects and measure their distance

Q11. What is the equation used to calculate the slant range distance in DME?

R = (T - 50) / 12.359

R = (T + 50) * 12.359

R = T / 50

Correct answer is – R = (T – 50) / 12.359

Q12. Radar works by sending out radio waves and then:

Listening for signals that bounce back from objects

Sending continuous sound waves

Ignoring the reflected signals

Correct answer is B – Listening for signals that bounce back from objects

Q13. DME provides which type of distance measurement?

Slant range distance

Horizontal ground distance

Bearing distance

Correct answer is – Slant range distance

Q14. What does SMR (Surface Movement Radar) mainly track?

Weather systems

Vehicles and aircraft on the ground at airports

Airplanes in the sky

Correct answer is B – Vehicles and aircraft on the ground at airports

Q15. What is the meaning of the term “slant range”?

Horizontal distance between aircraft and station

The straight-line distance between aircraft and station, including altitude

Time taken for the pulse to travel one way

Correct answer is – The straight-line distance between aircraft and station, including altitude

Q16. Which frequency band is commonly used for long-range air traffic control radar?

Ku band (12–18 GHz)

C band (4–8 GHz)

L band (1–2 GHz)

Correct answer is A – L band (1–2 GHz)

Q17. How does Monopulse Secondary Surveillance Radar (MSSR) differ from Primary Surveillance Radar (PSR)?

MSSR uses transponder replies to provide aircraft identity and altitude, while PSR detects all reflected signals

MSSR can only detect ground targets, whereas PSR can detect airborne targets

MSSR sends continuous waves, PSR uses short pulses

Correct answer is A – MSSR uses transponder replies to provide aircraft identity and altitude, while PSR detects all reflected signals

Q18. How often is the station identification (3-letter Morse code) transmitted by the DME ground station?

Every 30 seconds

Every 60 seconds

Every 10 seconds

Correct answer is – Every 30 seconds

Q19. Why is slant range usually greater than actual ground distance?

Because radio waves travel slower than sound waves

Because it includes altitude as well as horizontal distance

Because the signal is reflected multiple times

Correct answer is – Because it includes altitude as well as horizontal distance

Q20. Which radar type uses aircraft transponders to get information like identity and altitude?

Monopulse Secondary Surveillance Radar (MSSR)

Primary Surveillance Radar (PSR)

Surface Movement Radar (SMR)

Correct answer is B – Monopulse Secondary Surveillance Radar (MSSR)

Q21. Which navigation systems is DME commonly used with?

TACAN only

ADF and GPS

VOR and ILS

Correct answer is – VOR and ILS

Q22. (DME) operate on?

Primary radar principle

Continuous wave radar principle

Secondary radar principle

Correct answer is – Secondary radar principle

Q23. Doppler radar can measure the speed of an object by using:

Strength of the radio wave

Change in frequency of the reflected waves

The time delay of the signal

Correct answer is B – Change in frequency of the reflected waves

Q24. What is the function of the transponder in the DME system?

To measure the aircraft altitude

To transmit interrogation pulses

To receive interrogation pulses and send a reply

Correct answer is – To receive interrogation pulses and send a reply

Q25. How does radar determine the distance to an object?

By measuring the time delay between sending the pulse and receiving the echo

By measuring the strength of the radio signal received

By calculating the angle of the transmitted radio wave

Correct answer is B – By measuring the time delay between sending the pulse and receiving the echo

Q26. What type of dose† DME provide to support RNAV systems?

Only altitude measurement

Very accurate slant range data for position fixing

Only bearing information

Correct answer is – Very accurate slant range data for position fixing

Results