Service difficulty report · Hmu · Boeing 7377H4

Difficulty date
April 2, 2026
Submitted
April 7, 2026
Operation
Air carrier
Aircraft
N229WN
Make and model
Boeing 7377H4
Aircraft serial
32498
Aircraft time
66,674 hours, 40,051 cycles
Engine
Cfmint CFM567B242
Part
Hmu
Condition
Faulted
Location
Nr 1 Engine
Stage of operation
CL
How discovered
O
Nature of condition
R, J
Precautionary procedure
K

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

What was found

NR 1 ENGINE N1 ROLLED BACK 10% AT CLIMB OUT. REF TTG8Q01BFMVQ FOR REPLACEMENT OF HMU AND FUEL PUMP PACKAGE. PERFORMED TESTS 8; 12 AND 13 PER POWER PLANT TEST REFERENCE TABLE AMM 71-00-00. TESTS PASSED. A/C STILL NEEDS TEST 15 (85% N1 LEAK CHECK).;[02] PERFORMED TASK 71-00-00-SWA-823-F00 LEAK CHECK AFTER 85% N1 ENGINE RUN PER AMM 71-00-00. VERIFIED TASK MT 773-11-00 WAS COMPLIED WITH PREVIOUSLY.;[03] UPDATING PARTS IN MAINTENANCE REF TTG8Q01BFMVQ FOR INSTALLATION;[04] VERIFIED ALL TASKS WERE COMPLETED ACCORDINGLY PER MT 773-11-00 AND APPLICABLE AMM REFERENCES

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