Hi guys im having some problem with this 3 question. Need Help Please.
1) A Flux Valve
a) is used primarily to correct compass source information
b) is free of northerly turning error
c) generates signals comparable to a synchro rotor
d) directly feeds the cockpit indicator
2) Whether or not the aircraft has passed the nearest VOR station is indicated on a radial pictorial indicator by
a) a line
b) a series of dots
c) an arrowhead
d) there is no indication of whether the aircraft has passed the station
3) Which one of the following statements about a course select knob and cursor is False
a) The cursur resembles a carpet tack
b) The knob may be located on the pictorial indicator
c) The knob may be located on the autopilot control panel
d) The compass card reading of the cursur will not automatically match the digital reading obtained with the knob
Please advice and thank you
Avionics Questions
Moderators: North Shore, sky's the limit, sepia, Sulako, lilfssister, I WAS Birddog
Re: Avionics Questions
Navin,
These are basic training questions. One needs to understand how these systems work in order to answer the questions. I agree the questions are somewhat ambiguous and hard to decifer but in order to get an AME license in Canada you need to understand the systems and asking questions in this form is really not the way to do it.
1) A flux valve is part of a slaved compass system and is used to help correct the difference between your compass card lubber line reading and the actual aircraft magnetic heading. I guess one could say that its output is similar to that of a synchro transmitter output comparing the synchro rotor to the earth, but a synchro rotor is only one winding and a flux valve is three windings.
In a compass system the flux valve is the compass source so it can't correct itself...so...I don't know the right answer to that one...
2) "Passed the station" isn't the best term to use. To/From can be indicated two ways, an arrowhead or the word itself. I don't know what a Radial Pictorial Indicator is but an HSI or Pictorial Nav Indicator generally has and arrowhead and a CDI could have either an arrowhead or the words To and From...or both... but the arrow is always in view... and one has to figure out whether they've "passed the station" by how it's pointing relative to the selected course
3) Course select is usually not referred to as a cursor, it's a pointer or a number readout. Heading select is referred to as a cursor or a bug. Either Hdg select or Course select can be on the Indicator itself or remotely located
If you understood how the systems work you should be able to figure out these types of questions on your own....somehow...I guess...
These are basic training questions. One needs to understand how these systems work in order to answer the questions. I agree the questions are somewhat ambiguous and hard to decifer but in order to get an AME license in Canada you need to understand the systems and asking questions in this form is really not the way to do it.
1) A flux valve is part of a slaved compass system and is used to help correct the difference between your compass card lubber line reading and the actual aircraft magnetic heading. I guess one could say that its output is similar to that of a synchro transmitter output comparing the synchro rotor to the earth, but a synchro rotor is only one winding and a flux valve is three windings.
In a compass system the flux valve is the compass source so it can't correct itself...so...I don't know the right answer to that one...
2) "Passed the station" isn't the best term to use. To/From can be indicated two ways, an arrowhead or the word itself. I don't know what a Radial Pictorial Indicator is but an HSI or Pictorial Nav Indicator generally has and arrowhead and a CDI could have either an arrowhead or the words To and From...or both... but the arrow is always in view... and one has to figure out whether they've "passed the station" by how it's pointing relative to the selected course
3) Course select is usually not referred to as a cursor, it's a pointer or a number readout. Heading select is referred to as a cursor or a bug. Either Hdg select or Course select can be on the Indicator itself or remotely located
If you understood how the systems work you should be able to figure out these types of questions on your own....somehow...I guess...
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ScudRunner
- Rank 11
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Re: Avionics Questions
1) A Flux Valve
a) is used primarily to correct compass source information
b) is free of northerly turning error
c) generates signals comparable to a synchro rotor
d) directly feeds the cockpit indicator
e) it makes time travel possible
a) is used primarily to correct compass source information
b) is free of northerly turning error
c) generates signals comparable to a synchro rotor
d) directly feeds the cockpit indicator
e) it makes time travel possible
Re: Avionics Questions
Flux valves are free of northerly turning error. Why you would want an AME to know this is a mystery though.
Arrowhead
Arrowhead
Re: Avionics Questions
Those are the shittiest most useless "avionics" questions I've ever read. What idiot wrote those?
Re: Avionics Questions
Agreed...totallyThose are the shittiest most useless "avionics" questions I've ever read. What idiot wrote those?
I'm not sure that's correct...but maybe...I think that in the north compass systems are used in "Free" mode which eliminates the flux valve and only uses the Gyro.Flux valves are free of northerly turning error.
Northerly turning error affects the Stby compass and I'm pretty sure it affects the flux valve as well...just not the same way...I duno
....I believe you are referring to the "Flux Capacitor"...which is required to obtain the "121 Giga Watts"
Re: Avionics Questions
Those questions seem kinda awful- extremely poorly written...
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Colonel Sanders
- Top Poster
- Posts: 7512
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Re: Avionics Questions
What I wonder is ....
For people who's first language is NOT english,
how on earth could you ever answer questions
like this correctly?!
PS Want to write your ATPL exams in Cantonese?
For people who's first language is NOT english,
how on earth could you ever answer questions
like this correctly?!
PS Want to write your ATPL exams in Cantonese?
Re: Avionics Questions
Yeah its poor english but sadly its wrote by a Canadian Lecturer...So i wonder since English is his first language...He should take up cantonese Lol
Re: Avionics Questions
And yeah true i dont ever understand him half the time...he makes no freaking sence and his suppose to be our Lecturer...damn it
Re: Avionics Questions
Whoops. Flux valves are subject to northerly turning error. It's the gyro that prevents it.
Neverblue northerly turning error has nothing to do with being up north
.
Neverblue northerly turning error has nothing to do with being up north
.Re: Avionics Questions
I hate to wade in to a topic where really bad questions are posed, but here goes...
1. Flux Valves are free from northerly turning error which is really only an issue with direct reading compasses. The sensing coils on a flux valve is on a universal joint to allow it to remain relatively horizontal in turns but it is otherwise stationary. ie: it doesn't turn. Furthermore it has no magnetic field of its own so it can't be subject to dip or northerly turning error. The gyro has nothing to do with it.
2. The least incorrect answer is "an arrowhead". But, an arrowhead isn't used in every system. Sometimes its a TO or FROM indication. In one old radio (Genave 200) it was coloured lights. Regardless, the "arrowhead" isn't the singular indication of station passage. While on course inbound (arrow pointing ahead or TO) the pilot must watch as the arrow transitions to "OFF" or a flagged condition and then to point back (FROM). The momentary flagging and/or OFF is due to the "cone of silence" directly above the VOR station.
Another issue is the use of the term "radial pictorial indicator". Is he referring to the RMI or the HSI? If it's the RMI, station passage will be indicated by a reversal of the needle with the same interruption from the cone of silence as above.
3. The course can be indicated by various symbols. Unfortunately not all aircraft and avionics OEMs can agree to a standard. Some look like a carpet tack, some look like an arrow head some look like a "T". If you're using a GPS with course drive, the course bar will be automatically moved to the DTK. If you're using a VOR, it won't be automatically moved to the inbound or outbound course but it should definitely match the "digital" number you've entered.
The course knob can be located almost ANYWHERE in the cockpit. Sometimes on the HIS, sometimes on the FD or autopilot panel. Sometimes on a CRS/HDG panel. It all depends on the OEM and the cockpit layout philosophy.
I would be very interested in knowing what school this lecturer is employed by. I think these questions are a travesty.
1. Flux Valves are free from northerly turning error which is really only an issue with direct reading compasses. The sensing coils on a flux valve is on a universal joint to allow it to remain relatively horizontal in turns but it is otherwise stationary. ie: it doesn't turn. Furthermore it has no magnetic field of its own so it can't be subject to dip or northerly turning error. The gyro has nothing to do with it.
2. The least incorrect answer is "an arrowhead". But, an arrowhead isn't used in every system. Sometimes its a TO or FROM indication. In one old radio (Genave 200) it was coloured lights. Regardless, the "arrowhead" isn't the singular indication of station passage. While on course inbound (arrow pointing ahead or TO) the pilot must watch as the arrow transitions to "OFF" or a flagged condition and then to point back (FROM). The momentary flagging and/or OFF is due to the "cone of silence" directly above the VOR station.
Another issue is the use of the term "radial pictorial indicator". Is he referring to the RMI or the HSI? If it's the RMI, station passage will be indicated by a reversal of the needle with the same interruption from the cone of silence as above.
3. The course can be indicated by various symbols. Unfortunately not all aircraft and avionics OEMs can agree to a standard. Some look like a carpet tack, some look like an arrow head some look like a "T". If you're using a GPS with course drive, the course bar will be automatically moved to the DTK. If you're using a VOR, it won't be automatically moved to the inbound or outbound course but it should definitely match the "digital" number you've entered.
The course knob can be located almost ANYWHERE in the cockpit. Sometimes on the HIS, sometimes on the FD or autopilot panel. Sometimes on a CRS/HDG panel. It all depends on the OEM and the cockpit layout philosophy.
I would be very interested in knowing what school this lecturer is employed by. I think these questions are a travesty.
Re: Avionics Questions
ahh...well it has nothing to do with a gyro...gyroscopic principles have absolutely nothing to do with magnetism.Neverblue northerly turning error has nothing to do with being up north .
...and I never said it did have to do with being up north.
Actually the effect on the compass by northerly turning error is way more pronounced in the northern hemisphere of Canada where magnetic north is located...and the higher you are, the more northerly turning error affects the compass
It causes the compass to dip down towards the earth...or magnetic north... the closer you are to it.
The earth's magnetic lines of flux enter the earth at magnetic north. Which confuses the magnetic compass which is designed to rotate horizontally by lining itself up with these lines of flux. It either dips down or spins in circles. This is also why slaved gyro systems are usually operated in "Free Mode" in the North. It takes the flux gate out of the system...which also gets confused so to speak the closer you are to magnetic north because the lines of flux now come from all different directions.
It has nothing to do with the Gyro...which is why a DG is more reliable than a magnetic compass in the northern regions of Canada and regions of high earth mineral content.
It also affects the compass more in the regions of magnetic south as well...but it has always been termed Northerly Turning Error.
Inertial Navigation Systems and GPS have completely eliminated these characteristics that cause navigation problems because those systems do not work on magnetic principles.
Re: Avionics Questions
Neverblue, I wouldn't quite go that far.
When using GPS guidance, the pilot or autopilot is directed on a magnetic or true track. It's up to the compass system to provide the track error so the pilot can adjust the aircraft heading. Wind effects eventually wash out so that the airplane tracks the GPS.
Errors in the heading indicator will cause a track error. INS systems are marvellous and help immensely but aren't exactly widely used outside of transoceanic airliners and high end business jets. That doesn't help the guys slogging around the Arctic.
In Northern Domestic Airspace, the average free-gyro operating airplane requires regular heading correction updates from star/moon/sun shots. Of course there are those who just use GPS track, but that's not going to give you heading is it?
I don't know if that equates into gyro compasses being "more reliable" but magnetic compasses in the NDA are useless.
And let's not forget that generally gyro compasses are slaved when operated outside the NDA so we can't completely discount all of the associated errors.
When using GPS guidance, the pilot or autopilot is directed on a magnetic or true track. It's up to the compass system to provide the track error so the pilot can adjust the aircraft heading. Wind effects eventually wash out so that the airplane tracks the GPS.
Errors in the heading indicator will cause a track error. INS systems are marvellous and help immensely but aren't exactly widely used outside of transoceanic airliners and high end business jets. That doesn't help the guys slogging around the Arctic.
In Northern Domestic Airspace, the average free-gyro operating airplane requires regular heading correction updates from star/moon/sun shots. Of course there are those who just use GPS track, but that's not going to give you heading is it?
I don't know if that equates into gyro compasses being "more reliable" but magnetic compasses in the NDA are useless.
And let's not forget that generally gyro compasses are slaved when operated outside the NDA so we can't completely discount all of the associated errors.
Re: Avionics Questions
Agreed...
I am not a pilot so I am only speaking from experience through manufacture training and troubleshooting these systems.(and a lot of reading)
I wouldn't say that rotating gyro compasses are more reliable either...friction is inevitable!
I also realize that free directional gyros require constant correction by the pilot and Track is not Heading so using the GPS is not correct.
However, the newest AHRS systems, even in general aviation and the experimental/homebuilt market, use GPS data bases, solid state gyros and accelerometers and they are amazingly accurate at determining correct heading....Most of the technologies used are proprietary and exactly how this is done unfortunately is not common knowledge.
The Grand Rapids Technologies non-TSO'd system is simply awesome...
I should also correct my statement that INS/IRS do not use magnetic information for reference...some do
Thanks again for weighing in CID!
I am not a pilot so I am only speaking from experience through manufacture training and troubleshooting these systems.(and a lot of reading)
I wouldn't say that rotating gyro compasses are more reliable either...friction is inevitable!
I also realize that free directional gyros require constant correction by the pilot and Track is not Heading so using the GPS is not correct.
However, the newest AHRS systems, even in general aviation and the experimental/homebuilt market, use GPS data bases, solid state gyros and accelerometers and they are amazingly accurate at determining correct heading....Most of the technologies used are proprietary and exactly how this is done unfortunately is not common knowledge.
The Grand Rapids Technologies non-TSO'd system is simply awesome...
I should also correct my statement that INS/IRS do not use magnetic information for reference...some do
Thanks again for weighing in CID!
Re: Avionics Questions
There are no great secrets about AHRS systems; I've designed and built one. The tech is all out in the open, both in the research community and in the Hobby UAV community.
Beware of anything non-tso'd. The certification requirements are stringent and difficult to meet in all corner cases, and it's accuracy in the corner cases that you will be relying on when upside down in the clouds.
Beware of anything non-tso'd. The certification requirements are stringent and difficult to meet in all corner cases, and it's accuracy in the corner cases that you will be relying on when upside down in the clouds.
Re: Avionics Questions
...I'm not saying one can't develop their own system
I'm saying that companies like Honeywell and Garmin do not publish or give access to their schematics or software codes.
It's sometimes very difficult to get software protocols from these manufacturers when integrating different systems together in an installation...and you absolutely can not get any schematics for the box's internal circuits from Garmin anymore. Everything has to go back to factory for repair these days.
That's what I meant by common knowledge.
Out of curiosity photofly...what system did you develop? and who(manufacturer) uses it?
I'm saying that companies like Honeywell and Garmin do not publish or give access to their schematics or software codes.
It's sometimes very difficult to get software protocols from these manufacturers when integrating different systems together in an installation...and you absolutely can not get any schematics for the box's internal circuits from Garmin anymore. Everything has to go back to factory for repair these days.
That's what I meant by common knowledge.
Out of curiosity photofly...what system did you develop? and who(manufacturer) uses it?
