SDR ASAA2017041620471

Service difficulty report · Fmc · Boeing 737890

Difficulty date: April 16, 2017
Submitted: April 18, 2017
Operation: Air carrier
Aircraft: N592AS
Make and model: Boeing 737890
Aircraft serial: 35190
Aircraft time: 35,414 hours, 10,794 cycles
System (JASC): 3460 · Flight Management Computing Hardware System
Part: Fmc
Condition: Out Of Adjust
Location: Right
Stage of operation: TX
How discovered: O
Nature of condition: J
Precautionary procedure: O

As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.

What was found

FOUND A SINGLE FMC OPERATION NOTE IN SCRATCHPAD. AFTER ALIGNING IRS, THE FIRST OFFICER`S DISPLAY HAD A MAP FLAG FAILURE INDICATION. ACFT GROUNDED. CYCLED POWER TO FMC AT SAME TIME AND INDIVIDUALLY, NO HELP. SWAPPED FMC, NO HELP, RETURNED COMPUTERS TO ORIGINAL LOCATIONS IAW AMM 34-61-02. PERFORMED FMC SYSTEM TEST IAW AMM 34-61-00-730-801, FOUND DRAG FACTOR DID NOT MATCH. ADJUSTED DRAG FACTOR IN RT FMC TO -1.3 IAW TABLE 510. MAP FLAG CLEARED AND ALL GROUND VERIFICATION CHECKED GOOD.