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I'm Wondering About An Alarm On The RJ.

Posted: Sat Jun 16, 2007 3:16 pm
by aircanada333
EFIS COMP MON. It appears very often when in the middle of a tow move. What does it mean?

Thanks!

RE: I'm Wondering About An Alarm On The RJ.

Posted: Sat Jun 16, 2007 6:31 pm
by DashTrash
It's a comparator warning. It means that either the ADIs or HSIs do not agree with each other. (Displaying different attitude or heading information).

RE: I'm Wondering About An Alarm On The RJ.

Posted: Sun Jun 17, 2007 12:53 am
by avioniker
If we're talking about CRJ's the planes have Collins AHRS and it's extremely sensitive to magnetic disturbances like those caused by a tow vehicle.
6 degrees difference between the two systems gets you a warning.
 Smile

RE: I'm Wondering About An Alarm On The RJ.

Posted: Sun Jun 17, 2007 7:38 am
by avt007
AC Jazz aircraft are going to an all IRS fleet. The AHRS are a pain, and so is the Litton IRS, so they will have a Honeywell Laseref V in every CRJ, whether 100, 200, or 705. AC333, spefically it means EFIS comparison monitor, meaning that a parameter on the two EFIS displays do not agree. It will be accompanied by an amber box annunciator on the PFDs, next to the parameter that is causing the message. Probably heading, as the two fine gentlemen suggested.

RE: I'm Wondering About An Alarm On The RJ.

Posted: Sun Jun 17, 2007 12:29 pm
by aircanada333
Thanks guys for the quick answers!