# SDR 99ZZZX991

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: January 8, 1999
- Submitted: March 26, 2000
- Operation: General aviation
- Aircraft: [N494SP](https://openairdocs.org/aircraft/N494SP), registered now
- Make and model: Cessna 172S
- Registry model: [Cessna 172S](https://openairdocs.org/model/cessna-172s) (OpenAirDocs)
- Aircraft serial: 172S8035
- System (JASC): [7714 · Engine RPM Indicating System](https://openairdocs.org/jasc/7714)
- Part: Tachometer
- Condition: Mismanufactured
- Location: Cockpit
- Stage of operation: IN
- Nature of condition: W
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/99ZZZX991

## Discrepancy

ACCEPTANCE INSPECTION OF NEW CESSNA WITH 8.0 HOURS SINCE MANUFACTURE REVEALED THE TACHOMETER WAS IN ERROR.  A CALIBRATED TACHOMETER TESTER INDICATED THE AIRCRAFT TACHOMETER WAS 25 RPM'S LOW AT TAKEOFF AND 75 RPM'S LOW AT IDLE.  A REPLACEMENT TACHOMETER IS BEING INSTALLED.

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