Go Back  PPRuNe Forums > Flight Deck Forums > Tech Log
Reload this Page >

A320 lateral deviation on ND on final approach

Wikiposts
Search
Tech Log The very best in practical technical discussion on the web

A320 lateral deviation on ND on final approach

Thread Tools
 
Search this Thread
 
Old 21st Jun 2016, 21:17
  #1 (permalink)  
Thread Starter
 
Join Date: May 2002
Location: Florida
Posts: 104
Likes: 0
Received 0 Likes on 0 Posts
A320 lateral deviation on ND on final approach

Flown a few approaches recently on old A320s, (very old editions with the original FMGC). These are non-GPS aircraft.

Flying an ILS, passing the FAF, noticed that the ND shows a course deviation of 99.9L.

Anyone have any ideas on what is happening here? Or how to troubleshoot this? We have managed to get a few photos of this but at this point of the approach, its not the place for trouble shooting.

No other ECAM or MCDU scratch pad messages when this occurs.

Thanks for any suggestions.
Attached Images
File Type: jpg
IMG_3888-1.jpg (764.3 KB, 158 views)
File Type: jpg
IMG_0858.jpg (440.4 KB, 131 views)
767-300ER is offline  
Old 21st Jun 2016, 22:04
  #2 (permalink)  
 
Join Date: Apr 2004
Location: Planet Earth
Posts: 2,087
Likes: 0
Received 8 Likes on 7 Posts
Not familiar with the AB ND so its not obvious to me but what you describe sounds a lot like the map shifts we used to experience on our B757's before they installed GPS to provide updating.


Used to happen in areas of minimal or no radio updating and, oddly enough in areas of
massive updating, too much to consider I suppose.
stilton is offline  
Old 21st Jun 2016, 23:46
  #3 (permalink)  
 
Join Date: Mar 2002
Location: Seat 1A
Posts: 8,556
Received 74 Likes on 43 Posts
ND shows a course deviation of 99.9L.
"Tracking!"
Capn Bloggs is offline  
Old 23rd Jun 2016, 04:13
  #4 (permalink)  
 
Join Date: Aug 2013
Location: PA
Age: 59
Posts: 30
Likes: 0
Received 0 Likes on 0 Posts
Perhaps I am confused, but a glass cockpit without GPS?
underfire is offline  
Old 23rd Jun 2016, 05:04
  #5 (permalink)  
 
Join Date: Jun 1999
Location: Oztrailia
Posts: 2,991
Received 14 Likes on 10 Posts
Yeah amazing isn't it.......how did we navigate before GPS????

I flew glass cockpit 737 and 744 for years before GPS, we didn't get lost either.

I guess you wouldn't know about steam driven classic cockpits then?
ACMS is offline  
Old 23rd Jun 2016, 18:50
  #6 (permalink)  
Thread Starter
 
Join Date: May 2002
Location: Florida
Posts: 104
Likes: 0
Received 0 Likes on 0 Posts
yes, it is amazing...A320s flying without GPS, WAAS, LAAS, MLS etc.....
767-300ER is offline  
Old 23rd Jun 2016, 21:45
  #7 (permalink)  
 
Join Date: Aug 2013
Location: PA
Age: 59
Posts: 30
Likes: 0
Received 0 Likes on 0 Posts
I was just wondering why upgrade to glass and not GPS?
underfire is offline  
Old 24th Jun 2016, 02:38
  #8 (permalink)  
 
Join Date: Mar 2001
Location: I wouldn't know.
Posts: 4,497
Likes: 0
Received 0 Likes on 0 Posts
Because glass predates the widespread use of GPS? And it doesn't always makes economically sense to upgrade to GPS, especially on airbii retrofitting is very costly indeed.
Denti is offline  
Old 24th Jun 2016, 07:53
  #9 (permalink)  
 
Join Date: Apr 2010
Location: New Forest
Posts: 143
Likes: 0
Received 0 Likes on 0 Posts
I am not familiar with the AB display, but it does not seem to be too dissimilar to the 75/76. I presume that one pic is from before the FAF and the other after. Both show 99.9L (99.9L what? Miles? I expect so). Whether its in 'Tracking' or 'Course' would seem to be irrelevant. In pic 1 the ILS shows 267 degs at Victoria BC and in pic 2 298 degs at Edmonton Alberta. This is NOT a map shift - it has to be a software glitch of a fairly large proportion.. Also, there has been a dramatic veering of the wind - maybe there was, but I doubt it. In both cases the applied wind correction would appear to be approximately correct.
prober
Prober is offline  
Old 26th Jun 2016, 23:12
  #10 (permalink)  
 
Join Date: Aug 2013
Location: PA
Age: 59
Posts: 30
Likes: 0
Received 0 Likes on 0 Posts
Prober..I dont think they are the same approach, but simply 2 examples. (other than CYYJ is 269, not 267)
underfire is offline  
Old 3rd Jul 2016, 13:09
  #11 (permalink)  
Thread Starter
 
Join Date: May 2002
Location: Florida
Posts: 104
Likes: 0
Received 0 Likes on 0 Posts
Yes, they are just two examples where I have observed this happening.
767-300ER is offline  

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.