# NTSB LAX92LA350: Weatherly 620, N4623E, Stockton, CA, August 16, 1992

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: August 16, 1992, 07:19 local (14:19 UTC)
- Place: Stockton, CA
- Coordinates: 37.900657, -121.400352 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=37.9007&lon=-121.4004&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report May 26, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 27732
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX92LA350
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/27732/pdf
- Page: https://openairdocs.org/ntsb/LAX92LA350

## Probable cause

THE PILOT'S POOR INFLIGHT PLANNING AND VISUAL LOOKOUT.

## Sequence of events

In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf).

- In flight collision with object, maneuvering - aerial application
  - object - wire,static
  - in-flight planning/decision - poor, pilot in command (cause)
  - visual lookout - poor, pilot in command (cause)
- In flight collision with terrain/water, descent - emergency
  - terrain condition - open field
  - proper descent rate - not possible, pilot in command

## Analysis

AFTER COMPLETING AN AERIAL APPLICATION SWATH RUN THE PILOT ELECTED TO GO UNDER THE HIGH TRANSMISSION WIRES BUT FAILED TO OBSERVE THE LOWER WIRES. THE UPPER SECTION OF THE VERTICAL STABILIZER STRUCK THE LOWER WIRES CAUSING THE VERTICAL STABILIZER AND RUDDER TO SEPARATE. THE PILOT FLEW THE AIRPLANE TO STOCKTON AIRPORT, BUT LANDED SHORT BECAUSE HE WAS UNABLE TO MAINTAIN THE PROPER DESCENT RATE. THE PILOT DID NOT INDICATE THAT PRIOR TO COMMENCING THE SWATH RUN THAT HE FLEW OVER THE FIELD TO CHECK FOR OBSTACLES.

## Aircraft

- Registration: [N4623E](https://openairdocs.org/deregistered/N4623E-2009-09-23), registration cancelled 2009-09-23, S/N 1517 (OpenAirDocs)
- Reported make and model: WEATHERLY 620
- Registry model: [Weatherly 620](https://openairdocs.org/model/weatherly-620) (registry code 9630602) (OpenAirDocs)
- Category: Airplane
- Serial number: 1517
- Airframe hours: 1950
- Engines: P&W R-985 450 horsepower reciprocating
- Damage: Substantial damage
- Flight: Aerial application, Part 137
- Registered owner: James L. Copple
- Airworthiness certificate: Special, Restricted (Special)
- Last inspection: Annual, February 7, 1992, 438 hours before
- Departed: 103, LODI, CA
- Airport: SCK, Stockton, runway 29L, 2,996 × 75 ft, asphalt

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 50; commercial; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; flight hours: 1,997 total, 1,138 in this make and model, 1,997 as pilot in command

## Weather

- Conditions: Visual (VMC), Day
- Wind: 210° at 4 knots
- Visibility: 35 statute miles
- Lowest ceiling: none
- Temperature: 72 °F, dew point 55 °F
- Altimeter: 29.00 inHg
- Observed at: SCK, 1 nm away

## FAA reports on this event (1)

The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs).

- [Accident 19920816031329A](https://openairdocs.org/incident/19920816031329A), Aug 16, 1992: Wthrly 620, Stockton, CA, Substantial damage. Vertical stabilizer was torn off while flying under wires. Made it back to airport but crash landed short runway.

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.

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