Email
info@vayudootaviation.com
Phone No
+91 7276526726
become a pilot
Home
About us
courses
CPL
ATPL
RTR(A)
Airline Cadet Program
IGRUA Entrance Prep
B.Sc. Aviation
Pilot Training
INDIA
USA
CANADA
SOUTH AFRICA
NEW ZEALAND
EUROPE
Aircraft Type-Rating
Airbus A320
Boeing 737
Blogs
contact
CPL Test Series
Question Bank
Questions for DME
Answer the following questions
Test Mode
Training Mode
1. Distance Measuring Equipment (DME) uses radar principles to measure distance?
Plan range.
Slant range.
Horizontally.
Vertically.
2. The selection of the DME frequency for a ILS/DME installation is as follows?
The DME frequency has to be selected by the pilot.
When an ILS/DME is flown then the selection of the DME has always to be done manually.
The pilot has to insert the channel number and also the X or Y.
The DME frequency is paired with the localiser frequency so only the localiser frequency is set.
3. The effect of masking the DME antenna of the aircraft from the ground installation is that interruption of reception of DME signals results in?
The airborne installation switching to the memory mode for about 10 to 15 seconds.
The ground installation not sending any pulse-pairs.
The airborne installation switching directly to the search mode.
The signal controlled search circuit (SCS) blanking the DME display.
4. An aircraft is flying directly overhead a DME station at FL380. The indicated range will be approximately?
6.3 nm.
5.1 km.
6.3 km.
5.1 nm.
5. An aircraft DME receiver does not lock on to its own transmissions reflected from the ground because
They are not on the receiver frequency.
DME transmits twin pulses.
DME uses the UHF band.
The pulse recurrence rate are varied.
6. The ident of a DME in case of collocation with a VOR is as follows?
In 40 seconds the DME ident will sound once.
In 30 seconds the DME ident comes up 3 times at an audio frequency of 1350 Hz.
In case of collocation the DME ident is not necessary if the VOR ident is present.
The DME ident comes every 10 seconds at an audio frequency of 1020 Hz.
7. The aircraft DME receiver is able to accept replies to its own transmissions and reject replies to other aircraft interrogators because?
Transmission frequencies are 63 MHz different for each aircraft.
Aircraft interrogation signals and transponder response signals are 63 MHz removed from each other.
Pulse pairs are amplitude modulated with the aircraft registration.
The time interval between pulse pairs is unique to that aircraft.
8. What is the slant range error for an aircraft at 9000 feet absolute above a DME located at elevation 2000 feet, when the slant range is 12 nm?
0.31 nm.
1.42 nm.
0.57 nm.
0.09 nm.
9. Distance Measuring Equipment (DME) operates in the
UHF band and is a secondary radar system.
SHF band uses frequency modulation techniques.
VHF band and uses the principle of phase comparison.
UHF band and is a primary radar system.
10. A fix obtained by rho-rho navigation is based on information from two?
VORs.
VDFs.
NDBs.
DMEs.
11. How can a DME interrogator distipulsenguish between its own reply pulse-pairs and the reply pulse-pairs of other aircraft in the area, using the same DME station?
On the Y-channel the time interval between the pulses of an interrogator pulse-pair is 36 m/sec an of a transponder pulse-pair 30 m/sec.
The pulse repetition frequency of the pulse-pairs transmitted by the interrogator varies, for each interrogator there is a unique rhythm.
The DME transponder uses a slightly different, randomly varying, delay for each interrogating aircraft.
The time-interval between both pulses of consecutive pulse-pairs transmitted by the interrogator varies, for each interrogator the is a unique rhythm.
12. A DME station is located 7000 feet above MSL. An aircraft flying at FL 430 , 20 NM away from the DME station, will have DME reading?
20.88 NM.
15 NM.
21.35 NM.
17 NM,
13. A DME that has difficulty obtaining a "lock-on"? (NOTE: PRF= pulse recurrence frequency, PPS= pulses per second)
Alternates search mode with periods of memory mode lasting 10 seconds.
Stays in search mode but reduces PRF to max. 60 PPS after 15000 pulse pairs have been transmitted.
Stays in search mode but reduces PRF to max. 60 PPS after 100 seconds.
Stays in search mode without a reduction in PRF.
14. Which statement about the interrogation by DME interrogator is correct?
The interrogation starts when the interrogator has been warmed up sufficiently, whether pulse-pairs are received or not.
The interrogation can only take place if the Echo protection circuit has been locked.
The interrogation does not start before pulse-pairs of the tuned DME station are received.
The interrogation starts directly after the correct DME frequency has been selected on the frequency-selected panel by the pilot.
15. Aircraft position 34 degrees 15 minutes N 098 degrees E, magnetic variation 28 degrees W, FL280. PTV, VOR/DME position 36 degrees 12' N 098 degrees E, magnetic variation13 degrees E, In order to read the most accurate ground speed given by the DME receiver from his present position, the pilot must fly on which PTC radial?
332 degrees.
193 degrees.
167 degrees.
Aircraft will not receive DME information from PTC due to the line of sight.
16. What are the DME frequencies?
960 to 1090 MHz.
960 to 1215 MHz.
690 to 1215 MHz.
1030 to 1215 MHz.
17. If a DME beacon becomes saturated by interrogations it?
Switches off its identification.
Adjusts the gain to reply to the 100 strongest signals.
Adjusts its PRF to cope with all aircraft.
Replies to the nearest 100 aircraft.
18. A DME is located at MSL. An aircraft passing vertically above the station at flight level 360 will obtain a DME range of approximately?
7 nm.
11 nm.
8 nm.
6 nm.
19. The DME ground transponder has a PRF of?
2700 pulses per second.
27 pulses per second.
150 pulses per second.
1500 pulses per second.
20. An aircraft at FL 300, with a groundspeed of 300 kts, is about to pass overhead a DME station at MSL, The dame receiver is capable of determining ground speed. One minute before the overhead, DME speed and distance indication respectively are?
300 kts and 5 nm.
less than 300 kts and 7 nm.
300 kts and 7 nm.
less than 300 kts and 5 nm.
21. DME pulses are transmitted as pulse pairs. This is done?
To prevent lock onto the ground.
So that pulses are square and easily identified.
So that any radar emissions do not interfere with the DME equipment.
To increases the range.
22. ICAO specifications are that range errors indicated by Distance Measuring Equipment (DME) should not exceed
+ or - 1.25 NM plus 0.25% of the distance measured.
+ or - 0.5 NM or 3% of the distance measured whichever is the greater.
+ or - 0.25 NM plus 1.25% of the distance measured.
+ or - 0.25 NM plus 3% of the distance measured up to a maximum of 5 NM.
23. The time taken for the transmission of an interrogation pulse by a distance Measuring Equipment (DME) to travel to the ground transponder and return to the airborne receiver was 2000 microsecond. The slant range from the ground transponder was?
165 NM.
186 NM.
296 NM.
330 NM.
24. A typical frequency employed in Distance Measuring Equipment (DME) is
100 GHz.
100 MHz.
1000 MHz.
10 MHz.
25. The design requirements for DME stipulate that, at a range of 100 nm the maximum systemic error should not exceed?
Not more than +/- 0.25 nm.
Not more than +/- 3 nm.
Not more than +/- 1.5 nm.
Not more than +/- 1.25 nm.
26. Consider the following statement on horizontal/slant distance when using DME?
The difference between the two distance will be negligible for enroute Navigation when the indicated distance in NM is more than the height of the aircraft in thousands of feet.
The difference between the two is automatically compensated for in all DME equipment.
The operator in the aircraft should always make a mental increase to the indicated range, in order to compensate for the difference between the horizontal distance and slant distance.
The horizontal distance is always slightly longer than the slant distance.
27. When VOR and DME station are associated?
Their aerials will be mounted on top of each other.
Their signals must be tuned in by VOR and DME sets in the aircraft having common frequency control.
Their IDS will be in all respects identical.
They may be separated by as much as 600 metres if they are meant for enroute navigation.
28. A DME station is located 1000 feet above MSL. An aircraft flying at FL 310,20 NM away from the DME station, will have a DME reading of?
15 NM.
20.61 NM.
21.35 NM.
17 NM.
29. By using a random PRG the airborne DME can?
Prevent interference from random transmissions.
Recognise a beacon's reply among a mass of ground returns.
Distinguish between its own replies and those replies triggered by other aircraft.
Reduce the effect of weather interference.
30. An enroute DME and VOR that have the same morse code identification are associated and are?
Within 2000 feet of each other.
Within 600 feet of each other.
Always co-located.
Within 100 feet of each other.
31. DME is a radar type of facility and its maximum range is limited by?
The receiver sensitivity.
The transmitter power only.
The pulse repetition interval.
The height of the aeroplane.
32. An aircraft flying at FL360 is 10 nm plan range from a DM. The DME reading in the aircraft will be?
13.6 nm.
11.7 nm.
10 nm.
8 nm.
33. Of what use, if any, is a military TACAN station to civil aviation?
It is of no use to civil aviation.
It can provide DME distance.
It can provide a DME distance and magnetic bearing.
It can provide a magnetic bearing.
34. How many aircraft will DME accommodate before reaching saturation?
100.
50
150
120
35. The maximum number of aeroplanes that can be responded to by the DME ground facility is?
unlimited
150.
100.
10.
36. Groundspeed measurement using DME equipment is most accurate when flying?
Past the station at short range.
Towards the station at short range.
Directly over the station.
From the station at long range.
37. When in tracking mode, the DME airborne interrogator operates at? Note: PRR = Pulse Recurrence Rate
A PRR fixed at a rate selected from the range 5 to 25 PPS.
A PRR of 2700 PPS (Pulse Per Second).
A PRR of 150 PPS.
A PRR variable between 5 and 25 PPS.
38. When an aircraft at FL360 it is directly above a DME, at mean sea level, the range display will be?
0 nm.
12 nm.
9 nm.
6 nm.
39. In the which situation will speed indications on an airborne Distance Measuring Equipment (DME) most closely represent the groundspeed of an aircraft flying at FL400?
When tracking directly away from the station at range of 10 NM.
When tracking directly towards the station at a range of 100 NM or more.
When passing abeam the station and within 5 NM of it.
When overhead the station, with no change of heading at transit.
40. What happens when a DME in the search mode fails to achieve lock-on?
It alternates between search and memory modes every 10 seconds.
It stays in the search mode, but reduces to 60 pulse-pairs per second (PPPS) after 15000 pulse pairs.
It stays in the search mode at 150 PPPs.
It stays in the search mode, but reduces to 60 pulse-pairs per second (PPPS) after 100 seconds.
41. The most accurate measurement if ground speed by DME for an aircraft at 30000 feet will be when the aircraft is?
Passing abeam the beacon at 50 nm.
Overhead the beacon.
Tracking towards the beacon at 10 nm.
Tracking away from the beacon at 100 nm.
42. During a flight at FL260, a pilot does not receive any DME distance indication from a DME station located approximately 220 nm away. The reason for this is that?
Range to DME stations is always less than 200 nm.
Altitude is too high.
Aeroplane is below the line-of-sight altitude.
Aeroplane is circling around the station.
43. The DME counters are rotating continuously. This indicates?
The DME is receiving no response from the ground station.
The DME is trying to lock onto a frequency.
The DME is trying to lock onto a range.
The DME is unserviceable.
44. The DME line of Position is a circle with radius?
The ground distance and centre the aircraft.
The slant range and centre the DME station.
A ground distance and centre the DME station.
The slant range and centre the aircraft.
45. Which of the following will give the most accurate calculation of aircraft ground speed?
An ADF sited on the flight route.
A DME station sited across the flight route.
A DME station sited on the flight route.
A VOR station sited on the flight route.
46. During a flight at FL 210, a pilot does not receive any DME distance indication from a DME station located approximately 220 NM away. The reason for this is that the?
Aeroplane is below the 'line of sight' altitude
Range of a DME system is always less than 200 NM
Altitude is too high
Aeroplane is circling around the station
47. Regarding the DME system, which one of the following statement is true?
DME operates in the VHF frequency band.
The transponder reply carrier frequency differs by 63 MHz from that of the interrogation signal.
When passing overhead the DME station the DME will indicate 0.
The DME measures the phase difference between the reference and the variable signals to calculate the distance.
48. An aircraft at FL410 is passing overhead a DME station at mean sea level. The DME indication will be approximately?
6.1 nm.
6.8 nm.
6.8 km.
6.1 km.
49. Ground DME responders respond at a frequency?
63 MHz lower than the interrogation signal.
63 MHz higher than the interrogation signal.
63 MHz different from the interrogation signal, above or below.
The same as the interrogation signal.
50. A VOR and DME are frequency paired. The DME identification ends with Z. This denotes that?
The two beacons are co-located.
The two beacons are greater than 2000 metres apart.
The two beacons are supporting the same site, but are not co-located.
The beacons are at the same location but more than 1000 metres apart.
Submit
Make New Set
