# SDR ASMF202101009

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: November 11, 2020
- Submitted: January 22, 2021
- Operation: Air carrier
- Aircraft: [N782AM](https://openairdocs.org/aircraft/N782AM), registered now
- Make and model: Boeing 787-8
- Registry model: [Boeing 787-8](https://openairdocs.org/model/boeing-787-8) (OpenAirDocs)
- Aircraft serial: 37165
- Aircraft time: 22,865 hours, 2,600 cycles
- Engine: Ge GENX1B54
- Engine time: 22,868 hours, 2,601 cycles
- System (JASC): [7200 · Engine (Turbine/Turboprop)](https://openairdocs.org/jasc/7200)
- Part: Engine
- Condition: Damaged
- Location: Left
- Stage of operation: IN
- How discovered: 9
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASMF202101009

## Discrepancy

IN ACCORDANCE WITH CNR 20201109014 OF REMOTE DIAGNOSTIC GE/CFM SYSTEM AT MEX, THE LEFT ENGINE HAD A TREND CHANGE IN COMPRESSOR EFFICIENCY, DUE TO PISTON RING DISTRESS.  MAINTENANCE PERSONNEL PERFORMED THE LEFT ENGINE BORESCOPE INSPECTION OF THE OF THE HIGH PRESSURE COMPRESSOR, IAW SB 72-0348 INSTRUCTIONS.  DETECTING PISTON RING MATERIAL BETWEEN DIFFUSER AND HIGH PRESSURE COMPRESSOR STAGE 10 BLADES AND OGV FLOW PATH, SO THE LEFT ENGINE P/N GENX-1B76AP2G01 WITH S/N 956573, TSN 20533, CSN 2241, MANUFACTURER GENERAL ELECTRIC WAS REPLACED IAW AMM DMC-B787-A-G71-00-00-10B-520A/720A-A.  A FLUORESCENT PENETRANT INSPECTION PERFORMED ON 4 BOLTS MOUNT AFT, 4 BOLTS MOUNT FWD AND 4 NUTS MOUNT AFT, IAW AMM DMC-B787-G71-21-00, PMC-B787-81205-A5201-00 TYPE 1, METHOD C, LEVEL 3.  NO DAMAGES WERE FOUND AND LEFT ENGINE OPERATIONAL TEST WAS PERFORMED, IAW AMM DMC-B787-G71-00-0-15A-340A-A, TESTED CORRECT.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.