# SDR ARWA20041001

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: October 7, 2004
- Submitted: November 16, 2004
- Operation: Air carrier
- Aircraft: N791AL
- Make and model: Doug DC-8-62F
- Registry model: [Doug DC-8-62F](https://openairdocs.org/model/douglas-dc-8-62f) (OpenAirDocs)
- Aircraft serial: 46150
- Aircraft time: 66,241 hours, 19,529 cycles
- Engine: Pwa JT3D7
- Engine time: 52,008 hours, 19,118 cycles
- System (JASC): [7200 · Engine (Turbine/Turboprop)](https://openairdocs.org/jasc/7200)
- Part: Engine
- Condition: Vibration
- Location: Nr 2
- Part time: 52,008 hours, 19,118 cycles
- Stage of operation: CL
- How discovered: O
- Nature of condition: E
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ARWA20041001

## Discrepancy

NR 2 ENGINE HUMMING NOISE CHANGING IN PITCH DIRECTLY PROPORTIONAL TO VIBRATION IN THROTTLE, ALL OTHER PARAMETERS NORMAL, POWER RETARDED TO IDLE, HUMMING & VIBRATION STOPPED.  REMOVED AND REPLACED NR 2 ENGINE PER JOB CARD DC8-UM-003.  OPERATIONAL CHECK ON ENGINE RUN NORMAL.

---
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.