# NTSB LAX91FA333: Piper PA 28-181, N82716, Sonora, CA, July 28, 1991

- Type: NTSB accident investigation
- Classification: Accident · Fatal · Field investigation · Final report
- Date: July 28, 1991, 11:50 local (18:50 UTC)
- Place: Sonora, CA
- Coordinates: 37.979759, -120.389846 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=37.9798&lon=-120.3898&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: Fatal
- Injuries: 3 fatal
- Status: Completed, report February 8, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 27017
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX91FA333
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/27017/pdf
- Page: https://openairdocs.org/ntsb/LAX91FA333

## Probable cause

FAILURE OF THE FLIGHT INSTRUCTOR/PILOT-IN-COMMAND TO ADEQUATELY SUPERVISE THE FLIGHT AND TO MAINTAIN ADEQUATE AIRSPEED BY EXCEEDING THE CLIMB PERFORMANCE OF THE AIRPLANE. CONTRIBUTING TO THE ACCIDENT WAS THE PILOT-IN-COMMAND'S INADEQUATE PLANNING AND HIS SELECTION OF AN IMPROPER ALTITUDE FOR FLIGHT INTO RISING TERRAIN DURING HIGH DENSITY ALTITUDE CONDITIONS.

## Sequence of events

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

- Loss of control - in flight, maneuvering
  - aircraft performance,climb capability - exceeded (cause)
  - weather condition - high density altitude (contributing factor)
  - in-flight planning/decision - inadequate, pilot in command(cfi) (contributing factor)
  - altitude - improper, pilot in command(cfi) (contributing factor)
  - airspeed(vs) - not maintained, pilot in command(cfi) (cause)
  - stall - encountered, pilot in command(cfi)
- In flight collision with object, descent - uncontrolled
  - object - tree(s)
- In flight collision with terrain/water, descent - uncontrolled
  - terrain condition - mountainous/hilly (contributing factor)
  - terrain condition - rising (contributing factor)

## Analysis

A CERTIFICATED FLIGHT INSTRUCTOR AND TWO CERTIFICATED PRIVATE PILOTS WERE PARTICIPATING IN A MOUNTAIN FLYING TRAINING SEMINAR AS PART OF A THREE AIRPLANE FLIGHT.  THE ACCIDENT AIRPLANE WAS OBSERVED FOLLOWING A HIGHWAY UP A CANYON TOWARDS A 9,600 FOOT MOUNTAIN PASS.  THE AIRPLANE WAS OBSERVED ABOUT 200 FEET ABOVE THE GROUND, BELOW SURROUNDING CANYON WALLS.  THE TERRAIN RISES RAPIDLY AT THE END OF THE CANYON.  THE AIRPLANE WAS OBSERVED TO MAKE A LEFT TURN AWAY FROM HIGH TERRAIN,  PULL UP INTO A NOSE HIGH ALTITUDE, AND DESCEND FROM VIEW.  THE AIRPLANE WAS FOUND TO HAVE STRUCK A PINE TREE WITH THE  RIGHT WINGTIP, STRIKE ANOTHER TREE, AND THEN COLLIDE WITH A LARGE ROCK OUTCROPPING AT ABOUT 9,000 FEET MEAN SEA LEVEL.  AN INTENSE POST IMACCT FIRE CONSUMED ALMOST ALL OF THE AIRPLANE WITH THE EXCEPTION OF PORTIONS OF THE LEFT WING AND     TAIL.  THE DENSITY ALTITUDE WAS ABOUT 12,000 FEET.

## Aircraft

- Registration: [N82716](https://openairdocs.org/deregistered/N82716-1993-04-20), registration cancelled 1993-04-20, S/N 288290141 (OpenAirDocs)
- Reported make and model: PIPER PA 28-181
- Registry model: [Piper PA-28-181](https://openairdocs.org/model/piper-pa-28-181) (registry code 7102807) (OpenAirDocs)
- Category: Airplane
- Serial number: 28-8290141
- Airframe hours: 5152
- Engines: LYCOMING O-360-A4M 180 horsepower reciprocating
- Damage: Destroyed
- Fire: On-Ground
- Flight: Instructional, Part 91
- Operator: West Valley Flying Club Inc.
- Registered owner: Robert Brown
- Airworthiness certificate: Standard, Utility; Standard, Normal
- Last inspection: Annual, February 20, 1991, 86 hours before
- Departed: PAO, PALO ALTO, CA
- Destination: Q82, MARKLEEVILLE, CA

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 30; commercial, flight instructor; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; seat: right; toxicology performed; flight hours: 1,505 total, 1,404 as pilot in command, 197 in the last 90 days, 80 in the last 30 days

## Weather

- Conditions: Visual (VMC), Day
- Wind: 360° at 10 knots
- Visibility: 40 statute miles
- Lowest ceiling: none
- Temperature: 79 °F, dew point 48 °F
- Altimeter: 30.00 inHg
- Observed at: TVL, 40 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 19910728030419A](https://openairdocs.org/incident/19910728030419A), Jul 28, 1991: Piper PA28181, Sonora, CA, Destroyed, 3 fatal. Flying too low below canyon rim hit rock outcropping tryiny to turn crashed and burned.

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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