Narrative:

While we were handling a radar failed indication; the FMS message 'compare fuel quantity' appears on the FMS. The first officer and I agreed that it was probably erroneous but it could be a fuel leak. We ran the QRH for fuel leak. The QRH says: (note: an unexpected difference between the total fuel quantity indicated on EICAS and the total fuel quantity indicated on the FMS fuel management page may indicate a fuel leak condition.) we declared an emergency and landed at the nearest suitable airport. After crash and rescue confirmed that we did not have a fuel leak; we taxied to the gate and wrote up the discrepancies.

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Original NASA ASRS Text

Title: The flight crew of an ERJ-170 responded appropriately to a 'Compare Fuel Quantity' ECAM message; declared an emergency and landed at the nearest suitable airport. A concurrent failed weather radar; and the presence of convective weather; turned out to be surmountable complicating factors.

Narrative: While we were handling a radar failed indication; the FMS message 'COMPARE FUEL QUANTITY' appears on the FMS. The First Officer and I agreed that it was probably erroneous but it could be a fuel leak. We ran the QRH for fuel leak. The QRH says: (NOTE: An unexpected difference between the total fuel quantity indicated on EICAS and the total fuel quantity indicated on the FMS Fuel Management page may indicate a fuel leak condition.) We declared an emergency and Landed at the nearest suitable airport. After crash and rescue confirmed that we did not have a fuel leak; we taxied to the gate and wrote up the discrepancies.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.