PPRuNe Forums - B737 IRS Alignment Messages

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B737 IRS Alignment Messages

As per the FCOM

Quote:

When the Position information is contradictory IRS POS/ORIGIN DISAGREE is displayed.

Quote:

If an entered latitude/longitude position is not within 4 NM of the origin airport, the CDU scratchpad message VERIFY POSITION is displayed.

During line operations have only seen the IRS POS/ORIGIN DISAGREE. Any examples when VERIFY POSITION can be seen.

From U10.7 the VERIFY POSITION message was changed to specify the source that needed verifying, as in your example. So I think the old VERIFY POSITION message no longer exists as it has been enhanced.

Your second FCOM quote has probably not been updated to reflect the change.

Quote:

Originally Posted by CaptainSandL (Post 11193420)

Thanks Captain...

VERIFY POSITION is still being mentioned in the FCOM along with IRS POS/ORIGIN DISAGREE. This is on the B737MAX and B737NG FMCU14.0. With U10.7 VERIFY POSITION message has been enhanced as you mentioned. The enhancements include

VERIFY POS: FMC-FMC
VERIFY POS: FMC-GPS
VERIFY POS: FMC-RADIO
VERIFY POS: IRS-FMC
VERIFY POS: IRS-IRS
VERIFY POS: IRS-RADIO
VERIFY POS (On GND Only)

Both IRS POS/ORIGIN DISAGREE and VERIFY POSITION appear on GND as per FCOM. Then what's the difference ?