# Incident 19971223043609I: Lear 35A, Sioux Falls, SD, December 23, 1997

- Type: FAA incident report (Accident/Incident Data System), as reported
- Date: December 23, 1997, 17:30 local time
- Place: Sioux Falls, SD
- Airport: Joe Foss Field
- Phase of flight: Normal Cruise
- Operating rules: General operating rules (Part 91)
- Location: 43.5820° N, 96.7419° W: Placed by OpenAirDocs at JOE FOSS FLD (FSD), within about a mile (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=43.5820&lon=-96.7419&mi=10
- Aircraft: N684HA, a cancelled registration (https://openairdocs.org/deregistered/N684HA-2015-05-19) (OpenAirDocs)
- Registry model: Gates Learjet 35A (registry code 5170602, https://openairdocs.org/model/gates-learjet-35a) (OpenAirDocs)
- Registry engine: NONE (registry code 00000, https://openairdocs.org/engine/none) (OpenAirDocs)
- Reported make and model: LEAR 35A
- People aboard: 1
- Fatal injuries: 0
- FAA source: FAA Aviation Safety Information Portal (https://asip.faa.gov/)
- Page: https://openairdocs.org/incident/19971223043609I

## Narrative

As the FAA filed it, in capitals; the FAA replaces private details with ^PRIVACY DATA OMITTED^.

NARRATIVE: DURING CRUISE FLIGHT AT FL 390, AIRCRAFT BEGAN LOSING PRESSURIZATION. PILOT REQUESTED DESCENT TO FL 210. THE AIRCRAFT WAS STILL NOT MAINTAINING PRESSURIZATION, SO PILOT DESCENDED TO 11,000 TO TROUBLE SHOOT. UNABLE TO CORRECT PROBLEM, PILOT DIVERTED TO AND LANDED AT SIOUX FALLS, SOUTH DAKOTA. MAINTENANCE REPLACED A DEFECTIVE DUCT TEMPERATURE LIMITING VALVE.

## Other reports on N684HA (1)

Matched to the same aircraft by N-number and date.

- [Incident 19930529023809I](https://openairdocs.org/incident/19930529023809I), May 29, 1993: Lear 35A (N684HA), Windsor Locks, CT, Minor damage. Aileron problem after takeoff. Returned. Left tip tank touched ground and right wheel landed on grass beside runway

From the FAA Accident/Incident Data System. Reports are matched to registry aircraft by N-number and event date, checked against the reported make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. For accidents, the NTSB's own investigation is the fuller record.

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