# NTSB LAX91LA409: Cessna 206, N5123U, Jamul, CA, September 21, 1991

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: September 21, 1991, 15:30 local (22:30 UTC)
- Place: Jamul, CA
- Coordinates: 32.690147, -116.79914 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=32.6901&lon=-116.7991&mi=10
- Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 6 uninjured
- Status: Completed, report May 26, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 27371
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX91LA409
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/27371/pdf
- Page: https://openairdocs.org/ntsb/LAX91LA409

## Probable cause

THE PILOT'S FAILURE TO MAINTAIN DIRECTIONAL CONTROL DURING THE TAKEOFF GROUND RUN.  CONTRIBUTING TO THE ACCIDENT WAS THE SOFT WET RUNWAY CONDITION.

## Sequence of events

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

- Loss of control - on ground/water, takeoff - roll/run
  - terrain condition - soft (contributing factor)
  - terrain condition - wet (contributing factor)
  - directional control - not maintained, pilot in command (cause)
  - aborted takeoff - not performed, pilot in command (contributing factor)
- On ground/water encounter with terrain/water, takeoff - roll/run
  - terrain condition - berm (contributing factor)
- Nose over, takeoff - roll/run

## Analysis

THE PILOT STATED THAT IT WAS HIS FIFTH JUMP FLIGHT OF THE DAY.  HE STATED, THE RUNWAY HAD JUST BEEN WIDENED BY GRADING, WHICH LEFT HALF OF THE RUNWAY SOFT FROM THE GRADING.  IT ALSO CREATED A DIRT BERM OF EXCESS MATERIAL TO THE LEFT SIDE OF THE RUNWAY.  ON PREVIOUS TAKEOFFS HE INDICATED THAT THERE WAS A SLIGHT PULL TO THE RIGHT WHICH HE COUNTERED WITH RUDDER.  HE ALSO STATED THAT IT HAD BEEN RAINING AND THE GROUND WAS WET. THE PILOT LOST DIRECTIONAL CONTROL AND COLLIDED WITH THE DIRT BERM.

## Aircraft

- Registration: [N5123U](https://openairdocs.org/deregistered/N5123U-1993-10-20), registration cancelled 1993-10-20, S/N 2060123 (OpenAirDocs)
- Reported make and model: CESSNA 206
- Registry model: [Cessna 206](https://openairdocs.org/model/cessna-206) (registry code 2073302) (OpenAirDocs)
- Category: Airplane
- Serial number: 0123
- Engines: CONTINENTAL IO-520-A 285 horsepower reciprocating
- Damage: Substantial damage
- Flight: Other work use, Part 91
- Operator: Olen D. Mumma
- Registered owner: Olen D. Mumma
- Last inspection: Unknown, January 2, 2000
- Airport: NONE, Private Strip, runway 27, 2,000 × 70 ft, dirt

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 20; commercial; airplane ratings: single-engine land; medical: class 2, valid medical--no waivers/lim.; flight hours: 375 total, 75 in this make and model, 300 as pilot in command, 100 in the last 90 days, 70 in the last 30 days, 3 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 260° at 6 knots
- Visibility: 7 statute miles
- Lowest ceiling: 20,000 ft broken
- Observed at: SDM, 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 19910921043619A](https://openairdocs.org/incident/19910921043619A), Sep 21, 1991: Cessna 206CESSNA, Jamul, CA, Substantial damage. Left gear dug into soft mud on edge of strip during takeoff. Swung into dirt berm,collapsed nose gear. Nosed over.

## Other investigations on N5123U (2)

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 DEN71FXA14](https://openairdocs.org/ntsb/DEN71FXA14), Nov 25, 1970: Cessna U206 (N5123U), Casper, WY, substantial damage
- [NTSB UNK64X1839](https://openairdocs.org/ntsb/UNK64X1839), May 19, 1964: Cessna 206 (N5123U), Pleasant Hill, IL, substantial damage

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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