ILS encounters difficulties because of surrounding buildings and/or the terrain or interference from local music stations.

 

3                   

topographical conditions preclude the installation of ILS marker beacons.

 

4                   

meteorological conditions are likely to cause ILS ducting by super refraction.

 

 

Вопрос 199

Which one of the following correctly lists the major ground based components of a Microwave Landing

 

System (MLS)?

 

 

Ответы

1              

Separate azimuth and elevation transmitters, DME facility.

 

2                   

Separate azimuth and elevation transmitters, outer and middle marker beacons.

 

3                   

Combined azimuth and elevation transmitter, outer and inner marker beacons.

 

4                   

Combined azimuth and elevation transmitter, DME facility.

 

 

Вопрос 200

When performing an MLS approach, the aircraft:

 

 

Ответы

1                   

receives elevation information 13 times a second.

 

2                   

receives elevation and azimuth information 39 times a second.

 

3                   

receives elevation information 2 times a second.

 

4              

Receives elevation information three times as frequent as azimuth information.

 

Вопрос 201

Which one of the following methods is used by a Microwave Landing System (MLS) to indicate distance from

 

the runway threshold?

 

 

Ответы

1                   

Timing the interval between the transmission and reception of primary radar pulses from the aircraft to MLS station.

 

2                   

Timing the interval between the reception of sequential secondary radar pulses from the MLS station to the aircraft.

 

3              

A precision facility DME.

 

4                   

Measurement of the frequency shift between the MLS azimuth and elevation transmissions.

 

 

Вопрос 202

MLS can minimise multipath errors because:

 

 

Ответы

1                   

MLS has a larger beam width than ILS.

 

2                   

the transmission reverts to circular polarization when the beam is reflected by stationary objects.

 

3                   

the frequency of MLS is much higher than the frequency of ILS.

 

4              

The transmission can be interrupted to avoid reflection by stationary objects.

 

Вопрос 203

MLS frequencies and available channels are

 

 

Ответы

1                   

in the SHF band for the MLS elements and the VHF band for the DME, 100 available channels.

 

2                   

in the VHF- and UHF band, 40 available channels.

 

3                   

in the range 5060 - 5090 MHz, 200 kHz separation giving 150 available channels.

 

4              

In the SHF band, 300 kHz frequency separation giving 200 available channels.

 

 

Вопрос 204

Which one of the following is an advantage of a Microwave Landing System (MLS) compared with an

 

Instrument Landing System (ILS)?

 

 

Ответы

1                   

It does not require a separate azimuth (localiser) and elevation (azimuth) transmitter.

 

2              

It is insensitive to geographical site and can be installed at sites where it is not possible to use an ILS.

 

3                   

There is no restriction on the number of ground installations that can be operated because there is an unlimited number of frequency channels available.

 

4                   

The installation does not require to have a separate method (marker beacons or DME) to determine range.

Вопрос 205

Principle of operation of MLS is based on:

 

 

Ответы

1                   

frequency modulated duplex.

 

2                   

pulse interrogation.

 

3                   

analogue scanning beam.

 

4              

Time reference scanning beam.

 

 

Вопрос 206

Compared to the ILS, MLS has the following advantages:

 

 

Ответы

1              

Many different approaches to the same runway may be defined by a single set of ground equipment.

 

2                   

all approaches to all airfields will use the same channel, which means that the aircraft equipment will be a single-channel receiver.

 

3                   

no special receivers are required in the aircraft.

 

4                   

aircraft separation will automatically be arranged by the ground equipment.

 

 

Вопрос 207

Distance on MLS is measured by:

 

 

Ответы

1                   

measuring the time taken for the secondary radar pulse to travel from the MLS transmitter to the aircraft receiver.

 

2              

A DME co-located with the MLS transmitters.

 

3                   

measuring the time taken for the primary radar pulse to travel from the MLS transmitter to the aircraft receiver.

 

4                   

phase comparison between the azimuth and elevation beams.

 

 

Вопрос 208

A secondary radar can provide up to 4096 different codes. These 4096 codes can be used in:

 

 

Ответы

1              

All modes.

 

2                   

mode A only.

 

3                   

mode С only.

 

4                   

mode S only.

 

Вопрос 209

Mode С is selected on the aircraft SSR transponder, the additional information transmitted is

 

 

Ответы

1              

Pressure altitude based on 1013,25 hPa.

 

2                   

height based on QFE.

 

3                   

aircraft height based on sub-scale setting.

 

4                   

altitude based on regional QNH.

 

Вопрос 210

The selection of code 7600 on an aircraft SSR transponder indicates:

 

 

Ответы

1                   

unlawful interference with the planned operation of the flight.

 

2                   

transponder malfunction.

 

3                   

an emergency.

 

4