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How is the special position identification spi pulse transmitted ? [ Exam pilot ]

Question 208-1 : By the transponder as a result of the pilot pushing the ident button by the ssr interrogator if it is suspected that responses are received from aircraft that are located in the direction of the side lobes of the interrogator antenna by the ssr interrogator in order to request the identification of an aircraft automatically when the transponder responds to a mode a interrogation

The pilot may manually transmit a special position identification spi pulse when the 'ident' button on the pilot's transponder is pressed the benefit of the squawk 'ident' function is a manual identification of the aircraft the controller may ask via the radio communication frequency to 'ident' in case of any doubt of identification on the controller display upon acquisition of the spi pulse the transponder indication begins to flash on the display of the controller this produces a distinctive display so that a controller can pick out a particular aircraft by asking the pilot to squawk ident exemple 308 By the transponder as a result of the pilot pushing the ident button.By the transponder as a result of the pilot pushing the ident button.

The information available on an air traffic controller's screen about an ?

Question 208-2 : 1 ground speed 2 ssr 1 heading 2 primary radar 1 flight level 2 primary radar 1 pitch angle 2 ssr

Refer to figure . in practice the atc uses both the primary and secondary surveillance radar ssr systems together primary radar is a very useful equipment in determining the aircraft bearing and range but it has limitations for example if the target is too small targets can not be directly identified as a specific aircraft no transponder code or the radar signals suffer attenuation due to adverse weather such as storms for these reasons the atc uses both the primary and secondary radars the ssr supplements the primary radar when used in conjunction the primary radar is more accurate in determining the bearing and range of the targets than the ssr but the ssr provides multitude of additional information the atc controllers are therefore able to see the squawk code transponder code flight level provided by the transponder in mode c groundspeed calculated by the ssr ground facility based on the change of bearing and distance of the aircraft and a callsign provided by the transponder in mode s or assigned by the ground facility to a specific squawk code exemple 312 (1) ground speed; (2) ssr(1) ground speed; (2) ssr

The crew of a large jet aircraft want to use their airborne weather radar to ?

Question 208-3 : Becomes clear in the area of the storm shows green or yellow in the area of the storm shows magenta in the area of the storm shows hooks and scalloping in the area of the storm

Refer to figure .the airborne weather radar awr system fitted on large aircraft uses a primary radar system to look for reflections from precipitation in clouds the wetter and larger the precipitation the better the reflectivity the stronger the returns wet hail gives the best returns whereas ice crystals and dry snow do not give good radar returns stronger returns show up in red whereas weaker returns are green and yellow returns in the middle sometimes magenta is used to show areas of turbulence .the thin pencil beam of the radar scans the area ahead of the aircraft horizontally and the pilots can choose to manually adjust the vertical tilt of the beam this can be used to detect the tops or even bases of clouds given a small diagram and a basic knowledge of trigonometry the awr will only display returns when it is pointed at an area containing precipitation in this case a storm cloud when we tilt the radar beam high enough it will no longer see the cloud at which point the returns in that area of the screen will stop and this is the angle between the aircraft and the top of the cloud .given that we know the range from the storm which is already on our awr display we can calculate the relative height of the top of the cloud and therefore the approximate altitude of the top using the following formula .. cloud tops = range ft x radar tilt angle 1/2 beam width exemple 316 Becomes clear in the area of the storm.Becomes clear in the area of the storm.

Which of these is one of the main functions of the tilt control on an airborne ?

Question 208-4 : To search for areas of intense precipitation at different levels from the aircraft to keep the transmitter level during the aircraft’s pitch changes to allow the identification of clear air above a developing thunderstorm to allow the pilots to prevent ground personnel being exposed to radiation

The airborne weather radar awr system fitted on large aircraft uses a primary radar system to look for reflections from precipitation in clouds the wetter and larger the precipitation the better the reflectivity the stronger the returns wet hail gives the best returns whereas ice crystals and dry snow do not give good radar returns stronger returns show up in red whereas weaker returns are green and yellow returns in the middle sometimes magenta is used to show areas of turbulence .the awr is self stabilising at a chosen attitude using the irs attitude system it therefore does not respond to aircraft pitch/roll changes and can be set at a range of desired vertical tilt angles depending on what the crew want to detect the tilt settings are usually set high in the climb to detect weather that is about to be climbed into low in the cruise to detect the main cores of weather around and high again during the descent to reduce the amount of ground returns that show up on the display on modern aircraft there is often an auto tilt setting that is used to relieve pilot workload but can be overriden for manual tasks .in this question the best feature is the ability to scan other levels for more/less precipitation potentially to choose a better level to penetrate precipitation at it would not be useful to scan clear air above a developing thunderstorm as the cb cloud will continue rising so this data becomes useless very quickly exemple 320 To search for areas of intense precipitation at different levels from the aircraft.To search for areas of intense precipitation at different levels from the aircraft.

Which of the following describes a correct tilt setting for an airborne weather ?

Question 208-5 : During a climb the tilt needs to be decreased to scan for hazardous clouds a high tilt setting is helpful to detect a thunderstorm during a climb during any phase of flight the tilt of the weather radar will always be adjusted to the optimum tilt a low tilt setting should be used during descent if thunderstorms are expected

The airborne weather radar awr system fitted on large aircraft uses a primary radar system to look for reflections from precipitation in clouds the wetter and larger the precipitation the better the reflectivity the stronger the returns wet hail gives the best returns whereas ice crystals and dry snow do not give good radar returns stronger returns show up in red whereas weaker returns are green and yellow returns in the middle sometimes magenta is used to show areas of turbulence . . the awr is self stabilising at a particular attitude using the irs attitude system it therefore does not respond to aircraft pitch changes and can be set at a range of desired vertical tilt angles depending on what the crew want to detect the tilt settings are usually set high at take off and the beginning of the climb to detect weather that is about to be climbed into then reduced during the climb to spot the more violent cores of weather such as developing thunderstorms that could affect the aircraft it should be kept low in the cruise to detect the main cores of weather around and raised gradually during the descent to reduce the amount of ground returns that show up on the display exemple 324 During a climb, the tilt needs to be decreased to scan for hazardous clouds.During a climb, the tilt needs to be decreased to scan for hazardous clouds.

Flying at fl330 ahead of you there are thunderstorms above which is the proper ?

Question 208-6 : During a climb the tilt needs to be decreased to scan for hazardous clouds during any phase of flight the tilt of the weather radar will always be adjusted to the optimum tilt a low tilt setting should be used during descent if thunderstorms are expected a high tilt setting is helpful to detect a thunderstorm during a climb

The airborne weather radar awr system fitted on large aircraft uses a primary radar system to look for reflections from precipitation in clouds the wetter and larger the precipitation the better the reflectivity the stronger the returns wet hail gives the best returns whereas ice crystals and dry snow do not give good radar returns stronger returns show up in red whereas weaker returns are green and yellow returns in the middle sometimes magenta is used to show areas of turbulence . . the awr is self stabilising at a particular attitude using the irs attitude system it therefore does not respond to aircraft pitch changes and can be set at a range of desired vertical tilt angles depending on what the crew want to detect the tilt settings are usually set high at take off and the beginning of the climb to detect weather that is about to be climbed into then reduced during the climb to spot the more violent cores of weather such as developing thunderstorms that could affect the aircraft it should be kept low in the cruise to detect the main cores of weather around and raised gradually during the descent to reduce the amount of ground returns that show up on the display exemple 328 During a climb, the tilt needs to be decreased to scan for hazardous clouds.During a climb, the tilt needs to be decreased to scan for hazardous clouds.

The control panel of an airborne weather radar awr has a knob for adjusting the ?

Question 208-7 : To adjust the sensitivity of the radar receiver to widen the beam width of the radar signal to adjust the brightness on the display to increase the range on the display

Weather radar operation.the flight crew uses four features to operate the radar .. antenna tilt this is the angle between the centre of the beam and the horizon . range control of the nd this also has an essential influence on the optimum tilt setting . gain control this adjusts the sensitivity of the receiver . radar modes weather wx or weather + turbulence wx + t .gain is simply a control of how much of a return the awr airborne weather radar needs to pick up before it shows it on the display it is the sensitivity and can be adjusted as required to see the areas of worst precipitation and see exactly how bad they are on a case by case basis exemple 332 To adjust the sensitivity of the radar receiver.To adjust the sensitivity of the radar receiver.

On the control panel for an airborne weather radar there is a setting called ?

Question 208-8 : To change the shape and orientation of the transmission beam down toward the ground to assist navigation during the missed approach procedure to display the weather returns as an overlay on a map on the navigation display to display a modified route based on detected areas of intense precipitation

Refer to figure .learning objective 062 03 03 06 01 describe the navigation function of the radar in the mapping mode .the airborn weather radar awr has two different uses the primary one is of course to spot the areas of precipitation around the front of the aircraft to allow the pilots to avoid any dangerous areas of weather .the secondary use consists of tilting the awr more downwards below the horizon where it will look for reflections from the nearby land this is the 'mapping' mode and the awr actually has a separate beam transmission pattern that is best suited to receive accurate ground returns this can be used for navigation especially when dealing with coastlines and islands etc it used to be a very useful tool but is less useful in the modern era due to gps systems and moving map displays exemple 336 To change the shape and orientation of the transmission beam down toward the ground.To change the shape and orientation of the transmission beam down toward the ground.

Which of the following types of interrogations will a mode s transponder reply ?

Question 208-9 : Ssr and tcas interrogations ssr and ads b interrogations ssr and primary radar interrogations tcas and ads b interrogations

Learning objective 062 03 04 01 03 state that an airborne transponder provides coded reply signals in response to interrogation signals from the ground secondary radar and from aircraft equipped with traffic alert and collision avoidance system tcas ..mode s transponders are a natural continuation of the mode a and mode c transponders the mode a transponder is able to sent a 4 digit squawk code of which there are only 4096 individual identities mode s can handle 16 million different icao 24 bit aircraft addresses aas these aas are unique addresses registered to a particular aircraft there is also a much larger ability for transfer of information through mode s with many different aircraft parameters able to be transferred to the ground through els elementary surveillance or ehs enhanced surveillance systems and even a capacity of communications via datalink .mode s transponders use the same frequencies as mode a/c transponders so are backwards compatible and the ssr ground station produces different interrogation pulses to require a response from a particular mode s transponder or can 'all call' mode s transponders .the mode s transponder also receives information from tcas interrogations from nearby aircraft and replies with information such as range bearing and altitude to aid tcas separation mode s transponders are key to tcas operation and are very closely linked .the other options in these answers could not be correct in primary radar there is a reflection not a reply ads b is a system which relies on un requested output signals from the aircraft's transponder called squitters these squitters also aid tcas identification exemple 340 Ssr and tcas interrogations.Ssr and tcas interrogations.

In what ways can information from a typical airborne weather radar from a ?

Question 208-10 : Paths through areas of weather may be determined to ensure the safety and comfort of the flight all areas of turbulence may be identified to ensure the safety and comfort of the persons on board it is the prime source for navigating through mountainous areas due to its ability to detect terrain it detects ground features to enable navigation referenced to the ground when flying above clouds

Learning objective 062 03 03 06 03 explain how turbulence not cat can be detected by a modern weather radar .airborne weather radars have 2 main functions weather detection and ground mapping .pilots look ahead using their awr to pick the a route using areas of best weather and least turbulence turbulence can be detected by modern awrs but not all areas of turbulence as cat clear air turbulence has no associated particles which can reflect radar pulses it is invisible by definition .standard turbulence within clouds can be detected as the movement of the precipitation within the cloud causes a doppler shift on the returning radar pulses so the radar can form an idea of the air movement patterns in that area if they are erratic then turbulence exists in that region .this question is not referring to the mapping mode for one the mapping mode has been used for over 70 years so is not only used in 'modern' weather radars also the mapping is not very good at displaying mountainous terrain and would never be used for such applications it would also be very difficult to navigate via ground feagtures using it over the clouds as the clouds would reflect many pulses making it innacurate exemple 344 Paths through areas of weather may be determined to ensure the safety and comfort of the flight.Paths through areas of weather may be determined to ensure the safety and comfort of the flight.

The secondary surveillance radar ssr system used by aircraft transponders is ?

Question 208-11 : 1 interrogations 2 replies 1 transmission of pulse pairs 2 coded pulses 1 interrogations 2 pulse pairs 1 replies 2 interrogations

Learning objective 062 03 04 01 01 state that the atc system is based on the replies provided by the airborne transponders in response to interrogations from the atc secondary radar unlike a primary radar system which sends out pulses and then waits for any of those pulses to be reflected off an item such as an aircraft a secondary surveillance radar ssr sends out pulses which are interrogations of aircraft ssr transponders the interrogation is sent out of frequency 1030 mhz and the aircraft transponder then emits its own string of reply pulses on 1090 mhz a different frequency this method of radar usage has many benefits as the signals only need to be a quarter as powerful to travel half the distance primary radar signals have to travel to and object and then return to the station whereas with ssr the reply signals are freshly produced by the aircraft transponder so cover the air to ground journey reducing the required power of the radar ssr also has the benefits of being able to transmit a series of encoded pulses giving a 4 digit transponder squawk code of an aircraft in mode a operation and a pressure altitude readout when also using mode c more data can be sent out by mode s also and this is all encoded into strings of reply pulses emitted by the aircraft transponder exemple 348 (1) interrogations; (2) replies(1) interrogations; (2) replies

In general the operation of an aircraft's airborne weather radar awr whilst on ?

Question 208-12 : Only permitted whilst following certain precautions to safeguard health of ground personnel and to protect equipment totally prohibited unrestrictedly permitted in aerodrome maintenance areas permitted anywhere

062 03 03 04 01 explain why awr should be used with extreme caution when on the ground .airborne weather radar awr systems produce a powerful beam of electromagnetic radiation at a frequency of 9 10 ghz which means that it is microwave radiation microwave radiation is hazardous to organic material as it heats up water molecules and fats very quickly exactly the same as in a microwave oven this can cause tissue damage if exposed in high quantities .this is the reason that awrs should be switched off when on the ground unless proper precautions have been taken to avoid the ground crew being exposed to the radiation for testing etc exemple 352 Only permitted whilst following certain precautions, to safeguard health of ground personnel and to protect equipment.Only permitted whilst following certain precautions, to safeguard health of ground personnel and to protect equipment.

A young adult interested in becoming a pilot is invited into the cockpit they ?

Question 208-13 : Detecting significant weather and ground mapping detecting thunderstorms and turbulence ground mapping and controlling the gain of the beam detecting turbulence and functioning in wx+t mode

Learning objective 062 03 03 01 01 list the two main tasks of the weather radar in respect of weather and navigation .the trick with this question is to translate it into the relevant parts immediately the examiner has written a story to increase confusion and test the candidate's ability to pick out important information which also happens in lots of other atpl questions .this question can be translated into 'what are the two main tasks of the airborne weather radar ' the two main tasks of the airborne weather radar awr see learning objective above are detecting significant weather in order to avoid it and to use for ground mapping which used to be very common use of the awr but is less used these days .the question also mentions the tilt control knob but does not actually ask a question related to it it is just part of the story exemple 356 Detecting significant weather and ground mapping.Detecting significant weather and ground mapping.

Some of the advantages of secondary surveillance radar ssr in comparison to ?

Question 208-14 : 1 collects more data 2 of the active participation of the aircraft's transponder 1 enables the controller to have a more organised display 2 it uses longer interrogation pulses 1 provides coded replies 2 of its naturally higher transmission power 1 uses smaller aerials 2 it operates at higher frequencies

Learning objective 062 03 04 01 04 state the advantages of secondary surveillance radar ssr over a primary radar regarding range and collected information due to transponder principal information and active participation of the aircraft unlike a primary radar system which sends out pulses and then waits for any of those pulses to be reflected off an item such as an aircraft a secondary surveillance radar ssr sends out pulses which are interrogations of aircraft ssr transponders the interrogation is sent out of frequency 1030 mhz and the aircraft transponder then emits its own string of reply pulses on 1090 mhz a different frequency this method of radar usage has many benefits as the signals only need to be a quarter as powerful to travel half the distance primary radar signals have to travel to and object and then return to the station whereas with ssr the reply signals are freshly produced by the aircraft transponder so cover the air to ground journey reducing the required power of the radar . . ssr also has the benefits of being able to transmit a series of encoded pulses giving a 4 digit transponder squawk code of an aircraft in mode a operation and a pressure altitude readout when also using mode c more data can be sent out by mode s also and this is all encoded into strings of reply pulses emitted by the aircraft transponder exemple 360 (1) collects more data; (2) of the active participation of the aircraft's transponder(1) collects more data; (2) of the active participation of the aircraft's transponder

The tilt of an airborne weather radar is lowered whilst searching for ?

Question 208-15 : The greatest reflectivity occurs from wet hail and rain these elements usually exist in the lower levels of a thunderstorm the greatest reflectivity occurs from dry hail and snow these elements exist mainly in the lower levels of a thunderstorm ground clutter is more evident and therefore less likely to be confused with thunderstorm activity ground clutter enhances the display by automatically turning up the gain and increasing the likelihood of detecting thunderstorm activity

Refer to figure .los 062 03 03 05 02 describe appropriate tilt settings in relation to altitude and thunderstorms .airborne weather radar.an airborne weather radar is designed for avoiding severe weather not for penetrating it awr detects drops of precipitation such as rain and wet hail .at high altitude a storm cell may contain ice particles that have low reflectivity if the tilt setting is not correct the nd may display only the upper less reflective part of the storm cell over scanning as a result the flight crew may underestimate or not detect a storm cell at all .. the pilot would normally keep the tilt at 0º to 0 5º down during high altitude cruise however if there is a thunderstorm in front the pilot would want to turn the tilt down significantly about 5º down to see where the worst part of the storm is and how severe the core of the storm is .. . . use of the weather radar in accordance with the flight phase. . . flight phase. tilt control. . . taxi. away from ground personnel set the nd to the lowest range – as a rule set 15º up . . . take off. in the case of suspected adverse weather conditions manually and gradually tilt up to scan weather maximum 15º up in all other cases set the tilt to 4º up . . . climb. adjust the nd range as required and decrease the tilt angle as the aircraft climbs . generally set the tilt 5º to 7º up initially possibly steadily reducing with altitude . . . level flight/cruise. adjust the nd range as required regularly modify the tilt to scan weather ahead of the aircraft when the weather scan is completed adjust the tilt so that the ground returns appear on the top of the nd . at high altitude tilt is set to 0º to 0 5º except under adverse weather conditions . . . descent. set the tilt to about 5º up . . . approach. set the tilt to 4º up – which prevents the display of too many ground returns exemple 364 The greatest reflectivity occurs from wet hail and rain, these elements usually exist in the lower levels of a thunderstorm.The greatest reflectivity occurs from wet hail and rain, these elements usually exist in the lower levels of a thunderstorm.

What is shown on the atc radar screen when the pilot pushes the special ?

Question 208-16 : A flashing indication of the aircraft which is 'squawking ident' a flashing indication of all the aircraft which are not 'squawking ident' the removal of that aircraft from the radar display a flashing indication of all the aircraft on the radar display

Learning objective 062 03 04 02 07 state that in addition to the information provided on request from atc a special position identification spi pulse can be transmitted but only as a result of a manual selection by the pilot ident button ..the pilot may manually transmit a special position identification spi pulse when the 'ident' button on the pilot's transponder is pressed the benefit of the squawk 'ident' function is a manual identification of the aircraft the controller may ask via the radio communication frequency to 'ident' in case of any doubt of identification on the controller's display upon acquisition of the spi pulse the indication of that aircraft begins to flash on the display of the controller this produces a distinctive display so that a controller can pick out a particular aircraft by asking the pilot to squawk ident it is one of the many ways that controllers can link an aircraft on frequency to one on their radar display .note this question has been created from incomplete feedback so any further information particularly about the 4 options would be useful to refine the question thank you exemple 368 A flashing indication of the aircraft which is 'squawking ident'.A flashing indication of the aircraft which is 'squawking ident'.

What is the primary use of the radar fitted onboard a modern civilian transport ?

Question 208-17 : Detecting areas of wet convective weather transmitting data to atc for surveillance purposes detecting other aircraft providing the main input to an anti collision system

Radar has many uses in the world in aviation primary radar can be used to spot aircraft and weather but in the air aircraft tend to use it for just weather information that is why all large aircraft are equipped with an airborne weather radar .the airborne weather radar awr system fitted on large aircraft uses a primary radar system to look for reflections from precipitation in clouds the wetter and larger the precipitation the better the reflectivity the stronger the returns wet hail gives the best returns whereas ice crystals and dry snow do not give good radar returns stronger returns show up in red whereas weaker returns are green and yellow returns in the middle sometimes magenta is used to show areas of turbulence convective weather has bigger wetter precipitation which makes for stronger radar returns .the radar works the same as any other pulse radar by pointing in a particular direction and firing off a pulse of electromagnetic radiation in the microwave band then waiting for a reply from any potential reflections in that area it then measures the time of arrival of the reflection and uses this to calculate the distance from the target as the pulses travel at the speed of light .collision detection such as tcas is usually provided through secondary radar with pulses and replies rather than reflections exemple 372 Detecting areas of wet, convective weather.Detecting areas of wet, convective weather.

Radar has many uses in civil aviation for which tasks are both primary and ?

Question 208-18 : For atc to provide tracking of aircraft and manage traffic within a given airspace for the pilot to navigate and avoid areas of significant weather for atc to reduce the workload of the pilot by taking over the task of navigating for the pilot to detect other aircraft and reduce the risk of collision

Note this question is asking about primary and secondary radar not just one but when are both used .learning objective 062 03 01 01 01 name the different applications of radar with respect to air traffic control atc weather observations and airborne weather radar awr ..radar is an incredibly useful tool to aviation and is used in many forms for multiple different jobs in civil aviation .for starters it is split into primary and secondary radar primary radar is where a transceiver sends out electromagnetic pulses or waves that are reflected off items in the environment back to the transceiver and the time taken to travel to and from the object is measured to give an indication of its range the radar scans back and forth to figure out the direction of the object and in doing so gets a direction and distance so can plot the location on a display .secondary radar is where an interrogator sends out an interrogation signal transponders pick this signal up then send a reply signal which is good as it can carry more information such as squawk codes and altitudes as used in ssr secondary surveillance radar ..atc can use primary radar to track aircraft and weather and use secondary radar also to track aircraft and gain extra information about an aircraft ssr .pilots can use primary radar to track weather and navigate airborne weather radar as well as in the radio altimeter and can use secondary radar to detect other aircraft for collision avoidance acas/tcas as well as for dme which is technically a secondary radar system the aircraft is the interrogator exemple 376 For atc to provide tracking of aircraft and manage traffic within a given airspace.For atc to provide tracking of aircraft and manage traffic within a given airspace.

A mode s transponder knows that it is receiving interrogations from a mode s ?

Question 208-19 : Extra pulses are transmitted directly following the mode a and mode c pulses the ground interrogator will transmit extra pulses once it has had the initial reply from the airborne transponder the ground interrogator transmits the same pulses for all modes but for mode s the pulses are stronger only pulses specific to mode s are transmitted by the ground interrogator

Mode s does not transmit the p3 pulse but has an additional p4 pulse transponder without mode s will ignore p4 impulses p4 pulses can be either long or short in duration .the mode a/c/s all call interrogation elicits a mode a or mode c reply depending on the p1 p3 pulse spacing from a mode a/c transponder because it does not recognize the p4 pulse a mode s transponder recognizes the long p4 pulse and responds with a mode s reply icao annex 10 aeronautical telecommunications chapter 3 .this means that a mode s transponder transmits or receives extra pulses after the mode a and mode c transponder pulses exemple 380 Extra pulses are transmitted directly following the mode a and mode c pulses.Extra pulses are transmitted directly following the mode a and mode c pulses.

The pilot is given a 25 ft altitude increment which ssr mode does this apply to ?

Question 208-20 : Mode s mode a mode c mode a and c

Vertical performance.mode c provides pressure altitude information in addition to identification and position information compared to mode a the transponder message is reported in 100 feet increments which should be considered in terms of vertical separaction by atc .mode s has significantly better performance compared to mode c in terms of updating controller with altitude data the altitude may be reported with an accuracy of 25 feet exemple 384 Mode sMode s

A primary surveillance radar psr is capable of calculating a ?

Question 208-21 : Two dimensional position by measuring the bearing and travel time of the interrogation signal one dimensional position by measuring the bearing of the interrogation signal four dimensional position by measuring the bearing travel time height and time of the interrogation signal three dimensional position by measuring the bearing travel time and height of the interrogation signal

Refer to figure . primary surveillance radar psr primary surveillance radar psr operates by emitting radio wave pulses from a rotating antenna when these pulses encounter an aircraft or object some of the energy is reflected back to the antenna the psr uses a polar coordinate system to provide information on the detected targets it calculates the range which is the slant distance from the antenna to the target and the bearing which is determined by the antenna's azimuth range . the range is determined by comparing the time it takes for the pulse to be emitted and received utilizing the speed of light as the propagation speed it's important to note that the range provided is not the horizontal distance but the slant distance from the antenna to the target bearing . the measurement of bearing is achieved using the searchlight principle this involves concentrating radio pulses into narrow beams which can be accomplished by either shortening the wavelength or increasing the size of the aerial in advanced systems this is done electronically the narrow beam is then rotated at a constant speed when an echo is received the direction of the object is determined based on the direction of the beam at the time of receiving the echo this direction is measured from a fixed reference point or datum primary surveillance radar psr calculates bearing and range time difference of a target providing a two dimensional position exemple 388 Two-dimensional position by measuring the bearing and travel time of the interrogation signal.Two-dimensional position by measuring the bearing and travel time of the interrogation signal.

A primary route surveillance radar provides ?

Question 208-22 : Direction by measuring antenna azimuth range by signal travel during time no altitude 4 digit squawk code no direction no range no altitude altitude by angle elevation direction by antenna's angle of azimuth no range range by interrogating dme transponder altitude by interrogating mode c transponder no direction

Refer to figure . primary surveillance radar psr primary surveillance radar psr operates by emitting radio wave pulses from a rotating antenna when these pulses encounter an aircraft or object some of the energy is reflected back to the antenna the psr uses a polar coordinate system to provide information on the detected targets it calculates the range which is the slant distance from the antenna to the target and the bearing which is determined by the antenna's azimuth range . the range is determined by comparing the time it takes for the pulse to be emitted and received utilizing the speed of light as the propagation speed it's important to note that the range provided is not the horizontal distance but the slant distance from the antenna to the target bearing . bearing measurement in radar systems utilizes the searchlight principle where radio pulses are focused into narrow beams this can be achieved by reducing the wavelength or electronically enlarging the antenna in advanced systems the narrow beam is then rotated at a consistent speed by analyzing the direction of the received echo the bearing of the object can be determined based on the azimuth of the antenna at the time of receiving the echo this directional information is measured from a fixed reference point or datumprimary surveillance radar psr calculates bearing antenna's azimuth and range signal travel time of a target providing a two dimensional position altitude is not provided exemple 392 Direction by measuring antenna azimuth, range by signal travel during time, no altitude.Direction by measuring antenna azimuth, range by signal travel during time, no altitude.

A functional mode s transponder interrogated in mode a what is provided to the ?

Question 208-23 : Transponder code only transponder code and pressure altitude transponder code pressure altitude and aircraft address transponder code pressure altitude aircraft address and other flight data

The aircraft is interrogated from the ground station by a predetermined series of pulses on the carrier frequency of 1030 mhz its transponder then transmits a coded reply on a carrier frequency of 1090 mhz the modes of operation are mode a an interrogation to identify an aircraft . mode c an interrogation to obtain an automatic height read out of an aircraft referenced to 1013 hpa . mode s a development of the basic ssr fully compatible with the conventional mode a and c units providing air to ground ground to air air to air data link and height read out in increments of 25 ft mode s selective addressing . enables data exchange using communications protocols mode s data link can serve as an alternative or supplementary method for various atc services that are traditionally carried out using vhf voice communications this utilization of data link technology enhances the safety and reliability of the atc system by minimizing errors associated with voice based communication numerous types of messages and services within atc can benefit from data link backup like flight identification altitude clearance confirmation take off clearance confirmation new communication frequency for sector hand off pilot acknowledgement of atc clearance transmission to the ground of aircraft flight parameters minimum safe altitude warninga mode s transponder is fully compatible with conventional mode a and c ground units this means that if a mode s transponder is interrogated in mode a the transponder responds as if it was set in mode a providing aircraft identification transponder code to the atc radar screen exemple 396 Transponder code only.Transponder code only.

In a satellite assisted navigation system gnss/gps a fix is obtained by ?

Question 208-24 : Measuring the time taken for a minimum number of satellites' transmissions in known positions to reach the aircraft's receiver the aircraft's receiver measuring the phase angle of signals received from a number of satellites in known positions measuring the time taken for an aircraft's transmissions to travel to a number of satellites in known positions and return to the aircraft's receiver measuring the pulse lengths of signals received from a minimum number of satellites received in a specific sequential order

exemple 400 Measuring the time taken for a minimum number of satellites' transmissions, in known positions, to reach the aircraft's receiver.Measuring the time taken for a minimum number of satellites' transmissions, in known positions, to reach the aircraft's receiver.

What is the minimum number of satellites required by a gps in order to obtain a ?

Question 208-25 : 4 24 3 5

Admin .to carry out three dimensional 3d operation 4 satellites .to carry out two dimensional 2d operation 3 satellites exemple 404 4.4.

Gps satellites transmit on two l band frequencies with different types of ?

Question 208-26 : L1 coarse acquisition c/a with selected availability s/a l2 coarse acquisition c/a l1 precise p l2 for communications purpose

exemple 408 L1-coarse acquisition (c/a) with selected availability (s/a).L1-coarse acquisition (c/a) with selected availability (s/a).

Which of the following coordinate systems is used by the navstar/gps receiver ?

Question 208-27 : Wgs 84 ed 87 ed 50 pz 90

exemple 412 Wgs 84.Wgs 84.

Which of the following lists all the parameters that can be determined by a gps ?

Question 208-28 : Latitude longitude altitude and time latitude and longitude latitude longitude and time latitude longitude and altitude

exemple 416 Latitude, longitude, altitude and time.Latitude, longitude, altitude and time.

In a satellite assisted navigation system gnss/gps a position line is obtained ?

Question 208-29 : Timing the period that is taken for a satellite's transmission to reach the aircraft's receiver the aircraft's receiver measuring the phase angle of the signal received from a satellite in a known position timing the period that is taken for a transmission from the aircraft's transmitter/receiver to reach and return from a satellite in a known position the aircraft's receiver measuring the time difference between signals received from a minimum number of satellites

.the gps receiver computes the time taken for the signal to travel from the satellite to the receiver exemple 420 Timing the period that is taken for a satellite's transmission to reach the aircraft's receiver.Timing the period that is taken for a satellite's transmission to reach the aircraft's receiver.

In which frequency band do satellite assisted navigation systems gnss/gps ?

Question 208-30 : Uhf shf ehf vhf

Admin .each satellite broadcasts ranging signals on two uhf frequencies l1 1575 42 mhz and l2 1227 6 mhz .vor operating frequencies vhf.localiser vhf.marker beacon vhf.dme operating frequencies uhf.glide slope uhf.gnss/gps uhf.l1 and l2 frequencies used by navstar/gps uhf.ils localiser and glide slope vhf and uhf bands .microwave landing system mls shf.airborne weather radars shf.locator lf/mf exemple 424 Uhf.Uhf.

What is the minimum number of satellites required for the navstar/gps to carry ?

Question 208-31 : 3 24 5 2

Admin .to carry out three dimensional 3d operation 4 satellites .to carry out two dimensional 2d operation 3 satellites exemple 428 3.3.

Ignoring pulse length the maximum pulse repetition frequency prf that can be ?

Question 208-32 : 405 pps 782 pps 308 pps 810 pps

Admin .c/2f = 200nm . velocity of light = 162000 nm/sec .2f = 162000/200.2f = 810.f = 405 pps exemple 432 405 pps.405 pps.

Which of the following lists are all errors that affect the accuracy and ?

Question 208-33 : Satellite clock satellite ephemeris atmospheric propagation satellite mutual interference satellite ephemeris atmospheric propagation satellite to ground time lag atmospheric propagation satellite clock satellite mutual interference frequency drift satellite to ground time lag

exemple 436 Satellite clock; satellite ephemeris; atmospheric propagation.Satellite clock; satellite ephemeris; atmospheric propagation.

In order to carry out an independent three dimensional fix receiver autonomous ?

Question 208-34 : 6 7 5 4

Admin .raim receiver autonomous integrity monitoring is a technique whereby a receiver processor determines the integrity of the navigation signals raim is achieved by consistency check among pseudo range measurements .the basic raim requires 5 satellites but a 6th is necessary for isolating a faulty satellite from the navigation solution exemple 440 6.6.

Signal reception is required from a minimum number of satellites that have ?

Question 208-35 : 4 6 5 3

exemple 444 4.4.

The distance between a navstar/gps satellite and receiver is ?

Question 208-36 : Determined by the time taken for the signal to arrive from the satellite multiplied by the speed of light calculated from the doppler shift of the known frequencies calculated using the wgs 84 reference system from the known positions of the satellite and the receiver determined by the phase shift of the pseudo random noise code multiplied by the speed of light

Admin .the pseudorange is the pseudo distance between a satellite and a gps receiver .to determine its position a gps receiver will determine the ranges to at least four satellites as well as their positions at time of transmitting knowing the satellites' orbital parameters these positions can be calculated for any point in time the pseudoranges of each satellite are obtained by multiplying the speed of light by the time the signal has taken from the satellite to the receiver as there are accuracy errors in the time measured the term pseudo ranges is used rather than ranges for such distances exemple 448 Determined by the time taken for the signal to arrive from the satellite multiplied by the speed of light.Determined by the time taken for the signal to arrive from the satellite multiplied by the speed of light.

The reason why the measured distance between a navstar/gps satellite navigation ?

Question 208-37 : Calculated range includes receiver clock error measured distance is based on the pseudo random noise code movement of satellite and receiver during the distance calculation is not taken into account calculated range is based on an idealised keplerian orbit

Admin .satellites use an atomic clock actually 4 for high precision and continuously transmit their positions plus a code number in a set code at exactly the same time the set code appears to be random but isn't which is why it is known as pseudo random noise code it is the means by which a receiver recognises signals from a particular satellite .since the transmission time is known the distance the signal has travelled can be calculated from its arrival time the receiver matches each satellite's code with an identical copy in its database by comparing any shift with its internal clock it can calculate a pseudo range which is similar to comparing a broadcast copy of a song against one already playing on a cd player if they both started at the same time the received one would be slightly behind from the time delay if several 'songs' are received at the same time from multiple sources the gps receiver can correct for errors in its own clock and determine actual travel times .the principle used is that if three perfect measurements can locate a point in space four imperfect ones can eliminate clock offsets or cancel out some timing errors .an error is therefore deliberately introduced and algebra is used to compute where all possible points could intersect the result given is your position because it is calculated the word pseudo is used and the measured distance between a satellite and a receiver is called a pseudo range because the calculated range includes receiver clock error exemple 452 Calculated range includes receiver clock error.Calculated range includes receiver clock error.

What type of satellite navigation system navstar/gps receiver is most suitable ?

Question 208-38 : Multichannel sequential multiplex any hand held type

Admin .most gps receivers in use today are multi channel type meaning that they can track one satellite per channel a typical receiver will have 12 channels allowing it to track up to 12 satellites simultaneously .the receiver uses the latest almanac data to determine which satellites are visible at its location exemple 456 Multichannel.Multichannel.

The receiver aerial for a navstar/gps system should be mounted ?

Question 208-39 : On the upper side of the fuselage in the vicinity of the centre of gravity inside the tail fin to minimise the influence of reflections from the wing and fuselage in the vicinity of the receiver to avoid long transmission lines under the fuselage in order to receive correction data transmitted by d gps stations

exemple 460 On the upper side of the fuselage in the vicinity of the centre of gravity.On the upper side of the fuselage in the vicinity of the centre of gravity.

In the navstar/gps satellite navigation system re use of selective availability ?

Question 208-40 : Dithering the satellite clock shutting off selected satellites using a less accurate atomic clock in a satellite for signal processing offsetting satellite atomic clocks by a predetermined constant amount

.the c/a code coarse acquisition clear access or civil access is modulated on the l1 carrier only the p code precise or protected is modulated on both carriers .there are two limitations for civilian users namely selected availability and anti spoofing briefly referred to as sa and as respectively both deteriorate the achievable accuracy for civilian users significantly .selective availability sa the denial of full accuracy is accomplished by 'manipulating' navigation message orbit data epsilon and/or the satellite clock frequency dither so far only the satellite clock frequency has been manipulated with this dithering process the gps satellite clocks are artificially degraded by adding a signal with an unknown frequency and amplitude to the know clock behavior this is done to degrade the performance of gps for the 'normal' users both the frequency and amplitude of the added signal change rapidly over time the amplitude of this 'clock dithering' is of the order of 0 3 microseconds which corresponds to roughly 100 meters and the frequency is of the order of only a few minutes .this sa clock dithering limits the accuracy of real time position estimates to 25 meters rms exemple 464 Dithering the satellite clock.Dithering the satellite clock.

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