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mkear

IRS never aligns

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Since I installed the latest version of NGX and the 600 extender a couple of weeks ago, and FS2Crew Reboot a week ago,   I havent been able to align the IRS.       No one on the FS2Crew forum has this problem, so I'm thinking it's a problem with the NGX somehow.  

 

Here's what happens:  

 

I start cold and dark,   or if I start with the short Panel State,  I turn the IRS off,  wait at least 30 seconds  then ,  turn the IRS align knobs to "NAV".      The "ON DC" lights illuminate,  then extinguish.   The "ALIGN" lights start flashing  and that's how they will stay for an hour if i wait that long.   If I start with other panel states,  the "ON DC" lights are off when I'd expect them to be on.

 

I can go ahead and do everything else in the preflight,  including program the FMS but I can never turn on the autopilot or arm VNAV or LNAV 

 

Has anyone else experienced this?    Or is there a switch I'm not turning on that I should be?

 

I am currently thinking I should delete the NGX and remove it from the registry and start again, because I feel sure the problem is something went wrong with the installation of the last update.  

 

Cheers

Mike Kear

WIndsor, NSW, Australia 

 

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Before reinstalling the NGX, have you tried to load it with the panel state called "Default" and recreate the other panel state from there?

 

It usually fix any issues related to panel state and if the behaviour of the IRS is different from one panel state to the other (DC lights on or off for instance) I would suspect corrupted panel states to be the cause.

 

Also if you set the display selector of the IRS on HDG/STS after switching to NAV, do you see the count down timer? What does it display? You should read here the number of minutes remaining before alignment.

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Also the obvious, make sure the aircraft is stationary.  Good tip regarding panel states... I usually start with the default SHORT and do the minor mods that I like and then reuse it for months or longer.

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Thank you for your suggestions Budbud.   

I loaded the NGX with the default panel state,   then turned on the APU and shut down the engines so I didnt drive off through the countryside while I had my head up into the overhead panel.   

 

I turned the IRS switch to HDG/STS as you suggested.  (i've never touched that before  - I just figured it was some more eye candy and nothing to do with working the sim.) 

 

The IRS Display changed to  '0 ...  ... 08"  and it's remained that way for 10 minutes now and the "ALIGN" lights are still blinking.    I'm guessing it should  show   ... 08,      07,      06 .. etc shouldn't it? 

 

Cheers

Mike Kear

Windsor, NSW, Australia 

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One more take here: Make sure you uninstalled EVERYTHING pertaining to the old NGX properly as per instructions, including any panel states or saved flights.

Do the align lights blink while the countdown is going on ?

 

If you show 8 minutes I assume you have selected realistic align in the PMDG setup right ?

 

Also, did you enter the IRS position in the POS INI page in the CDU ? You can get it from the left or right GPS when they come in.

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Thanks for your suggestions alferra.   When I entered the irs position in the CDU,   the display on the overhead IRS display changed to "288" and the "ALIGN" lights stopped blinking,   but the "OK DC" lights still didnt come on, as I'd have expected them to. 

 

That means the IRS haven't aligned properly,  right?      

 

When I change the overhead IRS display to "Pos" from "HDG/STS"  it shows the same position as I entered through the CDU. 

 

And that would be the reason I can't arm LNAV and VNAV and turn on the autopilot when I'm at 5000 feet,  right?      Or am I looking at entirely the wrong issue? 

 

Cheers

Mike Kear

Windsor, NSW,  Australia. 

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Just out of interest,  I found a panel state called "PMDG 737NGX Tutorial #2 EHAM-LOWI Before Pushback" and I loaded that to see what would happen.

 

The overhead IRS display now shows "288   000"  and the VNAV and LNAV are armed.    But the "ON DC"  lights still aren't lit.     They are supposed to be, aren't they? 

 

Don't tell me i'm trying to fix something that isnt broken!!

 

Cheers,

Mike Kear

Windsor, NSW, Australia 

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(i've never touched that before  - I just figured it was some more eye candy and nothing to do with working the sim.)

 

Nothing is just eye-candy in the NGX, everything reflects the reality!  :P

 

First the DC light is not normally on. If would be on only if the normal power supply is not available (GPU, APU, engines gen). It shorlty light up when you switch the IRS selectors to NAV during the self-test but then should remain off.

 

Then the Align light should not be flashing in normal circumstances. It flashes when there is a problem with the position entered in the FMC.

 

I'm not gonna copy the whole chapter of the FCOM v2 but here is the reference:

FCOM v2, PDF page 839-842, Chapter 11.20.5

 

Have a look at it. Everything is well explained and easy to read. It should help you to fix you problem.

 

Once you have read the chapter, you can come back here for additional questions.

To me it is a not a bug but rather a misunderstanding on how the system works (not harm intended, sorry).

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Don't tell me i'm trying to fix something that isnt broken!!

 

Mike,

 

To be bluntly honest, this is probably the truth. In your posts, you seem to be hyperfocusing on the IRS panel, and on values you're not defining (apart from the LAT/LON). If you're not getting the countdown that Romain mentioned (and I'm guessing this is why you keep mentioning what values are up on that panel), then you should be aligned.

 

A big giveaway to alignment would be that no useful would be showing on the ND and PFD, like this:

2012-2-16_18-13-48-669.jpg

 

Have you flown the tutorial flights? Specifically Tutorial #2, which goes through a full power up from cold and dark. My bet is that you're missing some values on the FMC (specifically the PERF INIT values), which isn't allowing it to calculate the LNAV and VNAV paths.

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Just out of interest,  I found a panel state called "PMDG 737NGX Tutorial #2 EHAM-LOWI Before Pushback" and I loaded that to see what would happen.

 

The overhead IRS display now shows "288   000"  and the VNAV and LNAV are armed.    But the "ON DC"  lights still aren't lit.     They are supposed to be, aren't they? 

 

Don't tell me i'm trying to fix something that isnt broken!!

 

Cheers,

Mike Kear

Windsor, NSW, Australia 

 

The VNAV and LNAV can be armed only if the IRS are aligned which is the case there.

When you switch the IRS display selector to HDG/STS it will display:

_ the heading (HDG) and the maintenance status code (STS) if the IRS are aligned (here 288  000)

_ The time in minutes to the full alignment when the IRS are aligning.

 

The DC light is not ON (and it is normal) as your IRS are powered by a normal way (APU, GPU or engine gens).

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Ok.  I've been flying the NGX since it came out and getting on ok,  and in most cases I've been able to arm and use LNAV and VNAV.    

 

But plainly I've skipped over a lot of the stuff about the IRS and therefore I obviously dont know enough about it.    SO you're right folks, I need to know more.   I'll go and read that part of the FCOM and come back if/when I still have a problem.  

Oh and if (as is more than likely) the problem turns out to be a RTFM** problem, I'll tell you that too. 

 

Cheers

Mike Kear

Windsor, NSW, Australia. 

 

(** RTFM - a technical term in computer support.  stands for "Read The Damn Manual!"   ) 

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Since I installed the latest version of NGX and the 600 extender a couple of weeks ago, and FS2Crew Reboot a week ago,   I havent been able to align the IRS.       No one on the FS2Crew forum has this problem, so I'm thinking it's a problem with the NGX somehow.  
 
Here's what happens:  
 
I start cold and dark,   or if I start with the short Panel State,  I turn the IRS off,  wait at least 30 seconds  then ,  turn the IRS align knobs to "NAV".      The "ON DC" lights illuminate,  then extinguish.   The "ALIGN" lights start flashing  and that's how they will stay for an hour if i wait that long.   If I start with other panel states,  the "ON DC" lights are off when I'd expect them to be on.

 

 

...wait a tick.

 

Did you get the newest version of the NGX in order to use the newest version of FS2Crew and not remove the old version of the NGX before installing the new one?

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I didn't remove the old version.  I just installed the new version over the top of the old one, the way most upgrades/updates are done.      Did I RTFM there too and should have removed the old NGX first?    There is nothing in the installation notes that says the old version should be removed first.  

 

Jeez.    You'd think being in the computer industry myself,  and having run support departments, I'd have learned that woudlnt you. 

 

So if I was supposed to remove the old NGX before installing update SP1d  (ver 1.10.6461 ) the best thing would be to remove NGX completely,  and reinstall it from the SP1d (ver 1.10.6461) downloads woudln't it.    

Cheers

Mike Kear

Windsor, NSW, Australia. 

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When  the latest update   came  out  for  the ngx   for  the wxr   some users  just used  the  repair option for  which it  worked  and  others  it  didn't ,  the best  option  was  to completely uninstall   and  re install  making  sure you run  the operation  centre  first before   you did it  so  when   you re installed  and than run  the operation  centre   it  will  re install your liveries  again for  you.   For   the ngx  reboot  fs2crew to be  installed   you had  to either   manually  remove all the entries from the legacy fs2crew from the config  panel  or  the easiest   way  is  just  use the repair option of  the ngx installer,  than install  the ngx  reboot fs2crew

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Well the issue related to IRC aligning was a RTFM problem.   I didn't know what I was looking at meant.      I dkdn't know that when the "ALIGN" lights flash that means there's a problem with the address its trying to verify.      And entering the location manually in the CDU fixes that.    I thought those lights flashed when the align process was ongoing.  I expected to see the "ON  DC" light come up when the alignment process was finished.     WRONG!!      It was all there in the FCOM2 manual if i'd only read it. 

 

The problem with not being able to turn on the autopilot is still a mystery.  I am assuming its because I didnt have a setting of some kind somewhere that I hadnt selected.  Because when I went through the process carefully and made sure the aircraft was at sufficient altitude AGL before connecting it,  the autopilot worked fine.  

 

So it's all good, and all working now.       

Thank you everyone for all your suggestions.  In the process I've learned quite a lot.  I thought I was reasonably sure of the NGX and was able to fly it properly,  at least until it came to failures - I'm not studied in that area at all.   But no I found I had lots still to learn.    

That's good - it gives me plenty to keep it interesting  for a long time to come. 

 

 

Cheers

Mike Kear

Windsor, NSW, Australia. 

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