# Accident 19990808026749A: Wthrly 620B, Oberlin, KS, August 8, 1999

- Type: FAA accident report (Accident/Incident Data System), as reported
- Date: August 8, 1999, 07:45 local time
- Place: Oberlin, KS
- Damage: Substantial damage
- Phase of flight: Normal Cruise
- Operating rules: Agricultural (Part 137)
- Location: 39.8204° N, 100.5295° W: From the FAA, an estimate near the named town, within about 3 miles
- Nearby events: https://openairdocs.org/map.md?lat=39.8204&lon=-100.5295&mi=10
- Aircraft: N197SK, registered now (https://openairdocs.org/aircraft/N197SK) (OpenAirDocs)
- Registry model: Weatherly 620B (registry code 9630605, https://openairdocs.org/model/weatherly-620b) (OpenAirDocs)
- Reported make and model: WTHRLY 620B
- Reported engine: PWA R985*
- People aboard: 1
- Fatal injuries: 0
- Pilot flight hours: 6,742 total, 536 in this make and model
- NTSB investigation: [NTSB CHI99LA297](https://openairdocs.org/ntsb/CHI99LA297) (OpenAirDocs)
- FAA source: FAA Aviation Safety Information Portal (https://asip.faa.gov/)
- Page: https://openairdocs.org/incident/19990808026749A

## Narrative

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

(.19) ON AUGUST 8, 1999, AT 0745 CENTRAL DAYLIGHT TIME, A WEATHERLY 201B, OPERATED AND PILOTED BY A COMMERCIAL PILOT IMPACTED TERRAIN FOLLOWING A PARTIAL LOSS OF ENGINE POWER DURING AN AERIAL APPLICATION OF A FIELD LOCATED APPROXIMATELY 3 MILES WEST AND 1-1/4 MILES SOUTH OF OBERLIN, KANSAS. VISUAL METEOROLOGICAL CONDITIONS PREVAILED AT THE TIME OF THE ACCIDENT.  THE 14 CFR PART 137 AGRICULTURAL FLIGHT WAS NO OPERATING ON A FLIGHT PLAN.  THE PILOT SUSTAINED NO INJURIES.  THE FLIGHT DEPARTED THE PILOT'S PRIVATE AIRPORT AT 0700.  INSPECTION OF THE AIRCRAFT BY THE FEDERAL AVIATION ADMINISTRATION REVEALED THAT THERE WAS 28 GALLONS OF FUEL ABOARD.  THE RETAINING PLUG OF THE CARBURETOR FLOAT SHAFT ALONG WITH THE FLOAT SHAFT EXHIBITED CHATTER MARKS.  THE RETAINING PLUG WAS REMOVED AFTER TURNING IT 1/2 OF A TURN.  THE AIRCRAFT HAD ACCUMULATED A TOTAL TIME OF 847 HOURS.                           (-23)DURING SPRAY OPERATIONS THREE MILES WEST AND ONE AND ONE-FOURTH MILES SOUTH OF OBERLIN, KANSAS, AIRCRAFT EXPERIENCED COMPLETE LOSS OF POWER WHILE IN A LOW ALTITUDE TURN. SUBSTANTIAL DAMAGE OCCURRED WHILE LANDING IN A MUDDY PLOWED FIELD.                                                            (.4)THE AIRPLANE IMPACTED A MUDDY FIELD FOLLOWING A LOSS OF ENGINE POWER DURING AN AERIAL APPLICATION. THE BENDIX NA-R9B CARBURETOR FULCRUM SCREW AND THE CARBURETOR FLOAT PIVOT PIN EXHIBITED CHATTER MARKS.  THE FULCRUM SCREW WAS REMOVED AFTER TURNING IT 1/2 OF A TURN.  THE FULCRUM SCREW SAFETY WIRE WAS BROKEN.  THE NA-R9B FLOAT CARBURETOR TECHNICAL OVERHAUL MANUAL STATES THAT THE FULCRUM SCREW IS TO BE TORQUED TO A VALUE OF 100-120 IN-LBS.

## The NTSB's investigation of this event (1)

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

- [NTSB CHI99LA297](https://openairdocs.org/ntsb/CHI99LA297), Aug 8, 1999: Weatherly 201B (N197SK), Oberlin, KS, substantial damage. Probable cause: Engine failure due to an undertorqued carburetor fulcrum screw. Contributing factors were the muddy terrain and the low altitude of the aerial operation.

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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