# SDR 98ZZZX4548

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: September 19, 1998
- Submitted: March 26, 2000
- Operation: General aviation
- Aircraft: N501GS
- Make and model: Cessna 501
- Registry model: [Cessna 501](https://openairdocs.org/model/cessna-501) (OpenAirDocs)
- Aircraft serial: 5010012
- System (JASC): [3417 · Air Data Computer](https://openairdocs.org/jasc/3417)
- Part: Adc
- Part number: 4013241901
- Condition: Malfunctioned
- Location: Altitude
- Component: Honeywell, AZ241
- Stage of operation: NR
- Nature of condition: O
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/98ZZZX4548

## Discrepancy

UPON INITIAL 'POWER-UP' OF AIR DATA COMPUTER, ALTIMETER CLIMBS TO 4,000 FEET, AND DROPS VERY SLOWLY.  UPON FLIGHT DESCENT, ALTITUDE 'CAPTURE' IS SLOW, AND CAN INDICATE 200 TO 400 FEET IN ERROR.

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