CMA 9000, unexplained message
 

One question for the 225 drivers, and now the 175, or any aircraft fitted with the CMA 9000: what does the 'BORESIGHT DISCREPANCY' message mean, and, more to the point, what is a boresight discrepancy ?
The internet ressources and the operator's manual are not very clear.
A direct answer or a link would be much appreciated.
Thank you in advance.

ATN

All I can ascertain is that the message is showing a discrepancy between the boresight values that the FMS holds for the Embedded GPS/Inertial Navigation System (EGI) and the INS values that have been entered into the FMS.

Thank you, Pete, that's a start.

Boresight discrepancy is the "angle in degrees between the centreline of the EGI (embedded GPS/INS) and body centreline of the aircraft" in pitch, roll and yaw, according to the CMA 9000 installation and flight line manual. Correction values are entered through the MAINT page.

OK, now I get it.
THX