View Full Version : B777 A/P roll mode failure in LNAV

23rd May 2018, 14:03

i just saw this A/P roll mode behaviour (failure in-flight in LNAV) can someone pls provide a written explanation for this.
it can be simulated anytime anywhere. Looking for a reason that's all.

23rd May 2018, 17:42
goo.gl/ftPnv8 (https://goo.gl/ftPnv8)

a link to the video for anyone who doesn't like the plugin that can't be resized (not that there are many details to see here but still)

these automatic plugins should have a way to be disabled for a post. sometimes you just want a link not some youtube / twitter / whatever plugin.

23rd May 2018, 19:39
Wait, you say this can be simulated anytime and anywhere, but you're asking for the reason? I'm not sure I understand what you are asking for. That clicking sounds suspiciously like somebody pushing the NAV switch and activating CDU nav... If this is an actual failure occurring in flight then consult the MAT, a mode failure throwing the AUTOPILOT EICAS message should also leave a maintenance message on the MAT.

23rd May 2018, 22:37
STBYRUD - the ONLY SWITCH that is being touched/pressed is HDG SEL and back to LNAV in quick succession as you will see the roll FMA change. I am asking is why LNAV fails after that. It can be re-engaged back to normal. But there is a failure in between. I m asking why. :)