SDR ASAA2017111922647

Service difficulty report · Fmc · Boeing 737890

Difficulty date: November 19, 2017
Submitted: November 21, 2017
Operation: Air carrier
Aircraft: N587AS
Make and model: Boeing 737890
Aircraft serial: 35684
Aircraft time: 38,489 hours, 11,231 cycles
System (JASC): 3460 · Flight Management Computing Hardware System
Part: Fmc
Part number: 1762000101
Part serial: 001008
Condition: Failed
Location: Ee Bay
Part time: 48,832 hours, 16,382 cycles
Stage of operation: NR
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

EXPERIENCED 4 DUAL FMC FAILURES WITHIN AN HOUR. EACH TIME THE FMCS RECOVER BUT DUMPED ALL FMC DATA. NO FAILURES EXPERIENCED WITHIN LAST 3 HOURS OF FLIGHT. ACFT GROUNDED. REPLACED THE LT AND RT FMC COMPUTERS IAW AMM 34-61-02-400-801. LOADED ALL SOFTWARE IAW AMM 34-61-00/201, USING LAPTOP SYSTEM. ENTERED PERFORMANCE FACTORS IAW AMM 34-61-00-800-801, USING TABLE 501 IN AMM 34-61-00-730-801. DRAG FACTOR -1.3 FOR ETOPS WITH SPLIT SCIMITAR WINGLETS. VERIFIED ALL VALUES CORRECT, FMCS OPS TEST OK IAW AMM 34-61-00-710-801.