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AF330
11th Nov 2014, 08:53
Hi everyone!
Thought that this (sub) forum would be great to ask my questions here! ;) Because in TECH LOG, they were very nice but professionals. I am just starting! ;)
So here are my questions, on multiple subject: Radio system/ FMGS/ Navigation for the A320:

Ok se here we go:
I) A320 communications:

Check this please: http://www.smartcockpit.com/docs/A320-Communications.pdf

P1, 1.23.10 SEQ 001 REV23 says that the Radio management panel (RMP) permits us to tune a frequency. It then sends what we have entered by an electrical signal to the VHF/HF transceivers which is connected to the VHF and HF antennas. Here, the transceivers send an electrical signal to two different "places": to the antenna and the audio management unit (AMU). The AMU sends it to the audio control panel (ACP)

1) Is everything right?

Ok, let's continue: RMP 1 and RMP 2 are connected to each and every VHF/HF: VHF 1/ VHF 2/ VHF3 and HF1/ HF2 but RMP1 is generally used for VHF1 and HF1, RMP 2 is generally used for VHF 2 and HF2. RMP 3, on the overhead is for VHF3 which is connected threw RMP1 and RMP2.

2) Everything right?

The AMU: Audio management unit.

3) What is exactly it's use? Is it the AMP's computer?

4) What is a jack box?

5) On 1.23.20 P3, it says that hand mike and oxygen mask is connected to the AMU. Is it basically the boom with the microphone on the mike and the oxygen mask which is connected?

6) The data comes/goes to/from the AMP. What data goes to the AMU? For example, when we you turn the volume up, it sends an electrical signal to the AMU, which sends it to the transceivers who adjust the volume?

7) Are the transceivers connected to the microphones to adjust volume?*

Cabin Intercommunication data system: CIDS

8) Ok, so when we chose a frequency, it goes to the* VHF/HF transceivers. But when we talk with the cabin, it passes threw the CIDS?

9) Ok, so the lights, signals (no smoking...etc) pass by the CIDS?*

INT/RAD/Neutral

10) Ok, so when we press on INT, it let's the signal go/come from the cockpit to the cabin, you should have it ON, to be able to receive or to talk to the passengers/crew.

11) Neutral: You can only receive but you can not transmit (the most frequently used I imagine....)

12) RAD: You can talk/receive from the tower control

II) A320 GPS/IRS/FMGS

13) Basically 3 things give position to the FMGS:
a) GPS
b ) IRS/INS/IRU with inertia.
c) Beacons like VOR, NDB...etc. With the 2 VOR antenna for example!

14) The VOR antenna gives the CRS you are in and FMGS uses it for 2 things:
a) To calculate it's position to confirm the hybrid GPIRS position.
b ) For navaids displayed on the ND.
Am I right?

15) The plane needs to keep a small AoA on the wings to produce lift during cruise, it is also calculated by the flight management part (which will then send it to the FD)? Right?

16) I saw that it sometimes autotunes but still shows ---, how is that possible? Does the VOR antenna loses contact due to clouds...etc?

17) I saw a cockpit video and the pilot turned off the F/D, but the A/P was still working! Is the F/D computer still working and displaying bank and pitch for A/P (of course, we can't see it on the PFD, it's doing it inside the computer)

18) Check this please: http://www.efbdesktop.com/nav-flight-management/sys-14.1.6.html


Attitude is coming from the IRS/INS but the A/P follows FD bars. So is this data ONLY for FMGS (not for DMC, screens)? Because we had said that AP used to follow FD but if ATT coming from the FMGS is displayed by the FD, it would mean that AP is doing the same thing....

Lot's of questions quite important for me!*
Thanks a lot!

mikedreamer787
11th Nov 2014, 10:11
Because in TECH LOG, they were very nice but professionals.

I think this kid just insulted the lot of us. :cool:

Wodrick
11th Nov 2014, 10:31
This will take some time :)

AF330
11th Nov 2014, 10:50
Ha ha! ;)
No sorry! I just wanted to say that you ALL were professionals and it was difficult to find a forum like this. But as you are professionals, you like to answer to professional, it's normal! But I am a bigginer, so I was very happy to have found this sub-forum! ;)

@Wood: Are you writting my answer and saying it will take time? ;) Thanks a lot!!

Take care,
A.Roy

Wodrick
11th Nov 2014, 11:40
Ok se here we go: I am not convinced this is the best place questions or tech log.

I) A320 communications:

Check this please: http://www.smartcockpit.com/docs/A32...unications.pdf (http://www.smartcockpit.com/docs/A320-Communications.pdf)

P1, 1.23.10 SEQ 001 REV23 says that the Radio management panel (RMP) permits us to tune a frequency. It then sends what we have entered by an electrical signal to the VHF/HF transceivers which is connected to the VHF and HF antennas. Here, the transceivers send an electrical signal to two different "places": to the antenna and the audio management unit (AMU). The AMU sends it to the audio control panel (ACP)

1) Is everything right? More or less, lets forget antennas just consider them as part of a radio system. All audio, communication, Navigation and intercommunication goes into the AMU, it is just a junction box, a complicated one but just a junction box.

Ok, let's continue: RMP 1 and RMP 2 are connected to each and every VHF/HF: VHF 1/ VHF 2/ VHF3 and HF1/ HF2 but RMP1 is generally used for VHF1 and HF1, RMP 2 is generally used for VHF 2 and HF2. RMP 3, on the overhead is for VHF3 which is connected threw RMP1 and RMP2.

2) Everything right? That depends on the operators, but it is one way of connecting things up

The AMU: Audio management unit. See above

3) What is exactly it's use? Is it the AMP's computer? The AMP is a selector box it enables each crew member to listen and transmit on what they choose

4) What is a jack box? It is where you connect your headset, O2 mask hand mic and so on

5) On 1.23.20 P3, it says that hand mike and oxygen mask is connected to the AMU. Is it basically the boom with the microphone on the mike and the oxygen mask which is connected? Via a jack box, the headset has a boom microphone, the O2 mask has it's own microphone and there is a separate hand microphone

6) The data comes/goes to/from the AMP. What data goes to the AMU? For example, when we you turn the volume up, it sends an electrical signal to the AMU, which sends it to the transceivers who adjust the volume? Audio levels are fixed throughout the audio system. Each pilot can set his own received volume for each selected radio on the ACP

7) Are the transceivers connected to the microphones to adjust volume?* Microphone level is preset

Cabin Intercommunication data system: CIDS

8) Ok, so when we chose a frequency, it goes to the* VHF/HF transceivers. But when we talk with the cabin, it passes threw the CIDS? Yes

9) Ok, so the lights, signals (no smoking...etc) pass by the CIDS?* Most things electrical in the cabin go via the CIDS

INT/RAD/Neutral

10) Ok, so when we press on INT, it let's the signal go/come from the cockpit to the cabin, you should have it ON, to be able to receive or to talk to the passengers/crew. Not Pax, Int is between crew members, the Cabin staff have a handset (like a telephone) to talk amongst themselves and with the flight deck. PA is used to address the pax either by the flight deck or the Cabin staff.

11) Neutral: You can only receive but you can not transmit (the most frequently used I imagine....) You receive what you have selected on the ACP

12) RAD: You can talk/receive from the tower control You transmit on what you have selected on the ACP, you can only select one at once.

AF330
11th Nov 2014, 12:09
Thankd a lot!!!
Just small doubts remaining...... Will take a "little" time! ;)

Wodrick
11th Nov 2014, 18:43
A320 GPS/IRS/FMGS This is where I think you are most confused. There are things that are best left until you have a much more detailed understanding of Aircraft systems. CIDS is another, I know people who have been working Aircraft a long time who cannot understand CIDS

13) Basically 3 things give position to the FMGS: NO the ADIRU gives position(and attitude) to everything that needs it. The A320 does not have INS. It has the IRU part of the ADIRU. As all inertial reference derived position drifts over time the IRU derived position is corrected by GPS position.

14) The VOR antenna system allows you to select a course then capture and follow it either manually or the FMGS will do it. VOR does not give a position on it's own just the course selected. A pointer on the ND points to or from the beacon, and the ND also shows error from the course selected.

16) I saw that it sometimes autotunes but still shows ---, how is that possible? Does the VOR antenna loses contact due to clouds...etc? VOR is not affected by the weather. In normal use the Crew enter a route into the MCDU and the FMGS will fly the route and auto tune all the time. The dashes show that it is autotuned in this case, not no data.

17) I saw a cockpit video and the pilot turned off the F/D, but the A/P was still working! Is the F/D computer still working and displaying bank and pitch for A/P (of course, we can't see it on the PFD, it's doing it inside the computer) Now the A/P and the F/D are terminology throwbacks to when they were seperate items. At least since the A300 they are the same thing and while it is simplistic I find it convenient to look at the FD as displaying AP error so with the FMGS engaged it will generally show zero deviation as the FMGS has satisfied the demand. With the FMGS disengaged it shows commands that the crew has to satisfy. FD off just hides the display the FMGS continues in the selected mode.

18) Check this please: http://www.efbdesktop.com/nav-flight...ys-14.1.6.html (http://www.efbdesktop.com/nav-flight-management/sys-14.1.6.html)


Attitude is coming from the IRS/INS but the A/P follows FD bars. So is this data ONLY for FMGS (not for DMC, screens)? Because we had said that AP used to follow FD but if ATT coming from the FMGS is displayed by the FD, it would mean that AP is doing the same thing.... I am not sure what you are saying here Attitude (pitch and roll) is determined in the ADIRU.





15) The plane needs to keep a small AoA on the wings to produce lift during cruise, it is also calculated by the flight management part (which will then send it to the FD)? Right? Again I am not sure of the question, the FMGS flies the aircraft just as a pilot would. It is much more complex than you infer. I have tried to keep it simple.

AF330
11th Nov 2014, 21:24
Thanks a lot!!!!! You are great!
1) So when we speak inside the microphone, it goes to a jack box, then goes to the tranceivers which then sends it to the AMU and the AMP. Now the AMU knows our frequency and can send it to the AMP. Right?

2) What do the CIDS do? Are they just a place where everything going from cockpit to cabin transits?

3) So it will show --- only if WE have entered a CRS and a beacon frequency? Never when autotunes?

4) What do the Jack boxes do? Control volume?

5) The plane has to reduce a smal AoA, even during cruise to produce lift. So the AoA probes should send the AoA to the FMGS because pilots enter: FL330- for example- that's all. So the FMGS should always produce and calculate the required lift.

6) So the FD still works. You just have turned off the display by clicking on FD, right?

7) If we lose FMGS, do we lose Attitude? If no, does the attitude direcly comes from the IRU to the FD? Or is it always threw FMGS?

8) When we lose FMGS, we can still see our HDG...So are the IRU connected to the DMC?

9) When we enter HDG ABC in the FCU, the A/P should know what is our HDG.....So is the IRU HDG connected to the FMGS for managed mode and direcly to the A/P for selective mode?

Thanks! ;)

AF330
11th Nov 2014, 21:36
In fact, didn't get the difference:

FMGS sends what we have to do to the FD. The A/P follows the FD.
What is the difference between the FD which is displayed and the FD that the AP folliows? Does the AP follow the one on the PFD? So the real attitude is never shown? What happens when we enter an altitude/HDG on the FCU?

Thanks!

BenThere
11th Nov 2014, 21:47
Might I suggest you monitor everything the A320 is doing closely so as to ensure it is doing what you intended. You simply can't monitor enough!

Also, you learn by doing. Every A320 FO has made calls to company on guard, or answered ATC on inter phone. It's part of growing up on the thing.

The alt star has caused more altitude deviations than anything.

The A320 will do just about everything for you, but you MUST watch it, and know what it's doing.

AF330
11th Nov 2014, 21:56
Yeah of course! ;)
But I am not able to make out the different FD: the one AP follows, the displayed! ;)
And also other small things.... ;)

AF330
12th Nov 2014, 11:02
And yes, when I mean AoA, I want to say that you need lift, even in cruise so you need a small AoA, is that small AoA managed by FAC or FMGS?
What happens if we lose FMGS?? Where does the HDG signals (IRU) go?
To the HDG signals go to the AP (selective) and the FMGS (managed)?

Thanks!

Wodrick
12th Nov 2014, 16:59
So when we speak inside the microphone, it goes to a jack box, then goes to the tranceivers which then sends it to the AMU and the AMP. Yes. Now the AMU knows our frequency and can send it to the AMP. Right? NO AMU and AMP are just that AUDIO they care not about frequency. Frequency is either Manual or Autotune.

2) What do the CIDS do? Are they just a place where everything going from cockpit to cabin transits? CIDS is a system for the cabin. Everything in the cabin is controlled from the FAP via the CIDS Director in use (there are two) the only flight deck input is for PA. I will add a block diagram and a link to many pages about CIDS.

3) So it will show --- only if WE have entered a CRS and a beacon frequency? Never when autotunes?
Wrong way round Dashes = Autotuned. Frequency = Manual tuning.
4) What do the Jack boxes do? Control volume? We have done that, a Jack Box is passive, no active components, just a means oc connecting to the Audio System

5) The plane has to reduce a smal AoA, even during cruise to produce lift. So the AoA probes should send the AoA to the FMGS because pilots enter: FL330- for example- that's all. So the FMGS should always produce and calculate the required lift.

6) So the FD still works. You just have turned off the display by clicking on FD, right? Yes

7) If we lose FMGS, do we lose Attitude? If no, does the attitude direcly comes from the IRU to the FD? Or is it always threw FMGS? Attitude, Pitch, Roll and Heading (That is Magnetic heading not selected heading) are outputs from the ADIRU, they are output on a data bus and fed wherever required, and that's a lot of places.

8) When we lose FMGS, we can still see our HDG...So are the IRU connected to the DMC? Seven above

9) When we enter HDG ABC in the FCU, the A/P should know what is our HDG.....So is the IRU HDG connected to the FMGS for managed mode and direcly to the A/P for selective mode? Seven above
FMGS includes the AP part it is not seperate.


But I am not able to make out the different FD: the one AP follows, the displayed!
And also other small things.... It is the same thing


And yes, when I mean AoA, I want to say that you need lift, even in cruise so you need a small AoA, is that small AoA managed by FAC or FMGS?
What happens if we lose FMGS?? Where does the HDG signals (IRU) go?
to the HDG signals go to the AP (selective) and the FMGS (managed)?


You need to grasp that it is all the same thing, everything is connected to everything. There is no need to understand specific interconnections. It would have been better to start to understand something simpler like a 727 or 737-200 to get an understanding of basic systems before leaping to an Airbus, which is probably three generations more complex

AF330
12th Nov 2014, 20:37
Thanks a lot!!!!!!!!!

Here are my doubts:

1) What is FAP?

2) Didn't get your answer for n3! ;)
It shows --- in the corner of the ND. The navaids are raw data.
a) Can it show --- when it autotunes a frequency?
b) If yes, how is that possible?

3) When you write: "see above", I imagine that it is YES! ;)

4) For question 9, didn't get your answer! Imagine that we have lost FMGS or if we are in selective mode: the AP should know our current HDG to send the right signal to ELAC, so the IRU should be also directly connected to the AP, no?

5) When we enter data in the FCU, does it direcly go to the AP or does it go to the FMGS, FD....etc.? I hope that it direcly goes to the A/P because the selective mode still works with FMGS off! ;)

That's all! Thanks a lot Woodrick! You are very very helpful! ;)

Kind regards,
AF330

Wodrick
12th Nov 2014, 22:46
1) What is FAP?Fwd Attendants Panel

2) Didn't get your answer for n3!
It shows --- in the corner of the ND. The navaids are raw data.
a) Can it show --- when it autotunes a frequency?
b) If yes, how is that possible? At cross purposes I thought you were talking about the RMP as you had not mentioned the ND before

3) When you write: "see above", I imagine that it is YES! I wrote SEVEN above

4) For question 9, didn't get your answer! Imagine that we have lost FMGS or if we are in selective mode: the AP should know our current HDG to send the right signal to ELAC, so the IRU should be also directly connected to the AP, no? The FMGS IS the Autopilot. The FMC the FD it's all the same.

5) When we enter data in the FCU, does it direcly go to the AP or does it go to the FMGS, FD....etc.? I hope that it direcly goes to the A/P because the selective mode still works with FMGS off! See my last answer

For anybody else please remember I am trying to keep it simple.

AF330
13th Nov 2014, 06:22
Thanks.....
FMGS is the AP, but if we lose FMGS, do we lose A/P?

2) When you write 7 above, I imagine that it is connected, no??

Wodrick
13th Nov 2014, 07:06
I mean the answer seven answers this as well

Yes - but don't forget duplicated systems.

AF330
13th Nov 2014, 16:38
So we lose managed + selective mode of the A/P???

AF330
13th Nov 2014, 18:25
Hey....thought about this:

If we lose FMS (flight management system), we still have guidance so we have only lost the managed part...but if we lose FGS (flight guidance system), we basically lose FMGS and A/P (selective + managed!) because we don't know our position, but wr need our position in both cases....am I right?

Wodrick
13th Nov 2014, 23:01
Busy day here. Please don't forget all is duplicated, FMGS failure nothing is 'lost' switch to the other system.
I even think that dispatch is allowed on one FMGS but will stand corrected as it is eight years since I retired and I don't remember the MEL perfectly.

mikedreamer787
14th Nov 2014, 01:07
Wodrick yeah its allowed. Recall 1FD1 / 2FD2?

AF330
14th Nov 2014, 06:21
Yeah Wood......

But is at least my previous post right? Just want to get the concept. I just can't imagine FMS working without FGS!

If you lose FMGS, you lose A/P so basically you are flying manually to VOR'S/NDB's....etc.

Effluent Man
14th Nov 2014, 07:57
When I saw this thread I thought it was about something unspeakable that Muslims did to young girls on planes.

Keef
14th Nov 2014, 09:58
I'm missing something here. This sounds awfully like geeky techie. Someone explain to me please where is the "jet blast" innuendo that I can't see.

mikedreamer787
14th Nov 2014, 10:24
This sounds awfully like geeky techie

Same thing I said at Toulouse 10 years ago
when I dun the 320 CBT. After many many
years previously on Boeings (incl the B738,
B744, and my fave the venerable 727-200)
it was pure culture shock - and still is.

The frogs invent huge amendments to their
Systems, SOP etc on a yearly basis cos they
couldn't get their act together from day One,
and that was back in '88 after the Chainsaw
prang.

In 10 years they've changed the method of
determining LDG and TO Performance four
bloody times, and becomes more complex
each time. On the '47 I could spit out the
limiting weights, speeds, etc for a snowy
contaminated icy runway in a minute flat.
This frigging thing takes me forever.

You can't go and inject JB innuendo in Airbi
threads - just as you can't inject anything
humorous where the French are concerned.
Learnt that in Tech Log a while back.

Anyway nuff said. Wodrick obviously enjoys
having this tete-a-tete with a school kid so
I won't butt in further. :oh:

AF330
14th Nov 2014, 16:47
Ok, my last question:

If we lose FMS (flight management system), we still have guidance so we have only lost the managed part...but if we lose FGS (flight guidance system), we basically lose FMGS and A/P (selective + managed!) because we don't know our position, but wr need our position in both cases....am I right?

Thanks

Wodrick
14th Nov 2014, 17:39
Please try, It is a FMGS, it lives in one box, you don't loos a bit you loose the lot an switch to the other FMGS. You create problems where none exist.

I have been trying to get a schematic into e-mail format but can't. I can snip it but you can't read it as it's too small and I can't send 450 pages of chapter 22.

AF330
14th Nov 2014, 17:48
Thanks Wod....

Ok, so if we lose FGS, flight guidance system: GPS and IRU.
What will happen? A/P stops?

Thanks....trying to understand!

Wodrick
14th Nov 2014, 18:00
No just switch to the alternate systems and carry on. That is why all is duplicated, system redundancy.

AF330
14th Nov 2014, 18:49
Ok...;let me get this:

1) FMC/FMS manages the managed part of the A/P, right?
2) FMC/FMS sends signals to the FD, right?
3) FMC/FMS sends signals to the A/THR, right?
4) FMC/FMS calculates fuel...etc. right?
5) FMC/FMS uses the FGS to know the position, right?

6) FGS calculates R-NAV precession...etc. Right?
7) FGS sends the position to the DMC's to display it on the ND, right?
8) FGS sends the plane's POS to the FMC/FMS, right?

9) FMC/FMS + FGC/FGS = FMGS/FMGC, right?

Thanks a lot....

Wodrick
14th Nov 2014, 18:56
1) FMC/FMS manages the managed part of the A/P, right?
2) FMC/FMS sends signals to the FD, right?
3) FMC/FMS sends signals to the A/THR, right?
4) FMC/FMS calculates fuel...etc. right?
5) FMC/FMS uses the FGS to know the position, right?

1 to 5 broadly yes

6) FGS calculates R-NAV precession...etc. Right? Not sure without reading which I am not equipped to do any more
7) FGS sends the position to the DMC's to display it on the ND, right? No Position from ADIRU to all that need position
8) FGS sends the plane's POS to the FMC/FMS, right? Well it is all the same box so if you want yes.




9) FMC/FMS + FGC/FGS = FMGS/FMGC, right?

I suppose so Flight Management Guidance Computer is most of the whole.

AF330
14th Nov 2014, 18:59
Thanks a lot Wod....

So I take mostly each and every question as a YES!

So, know, we lose FMS, FMGS will automatically revert to selective mode. So know, will the FGS send signals to FD?

Pelikal
14th Nov 2014, 23:00
What the **** is this all about?:cool:

Wodrick
14th Nov 2014, 23:03
So, know, we lose FMS, FMGS will automatically revert to selective mode. So know, will the FGS send signals to FD?

If I understand the question correctly then yes

AF330
15th Nov 2014, 06:31
Great....

So when we enter something in the FCU, selective mode, the signal goes to the FGC and not the FMC, for security (if we lose FMC), right?

Or does the FCU send the signal to the FGC and the FMC? If FMC fails, FGC will send the signal.....

Thanks to tell me when FCU sends the info! ;)