# NTSB LAX85FA048: Cessna 172M, N9589V, Lake Isabella, CA, November 23, 1984

- Type: NTSB accident investigation
- Classification: Accident · Fatal · Field investigation · Final report
- Date: November 23, 1984, 12:40 local (20:40 UTC)
- Place: Lake Isabella, CA
- Coordinates: 35.640689, -118.460487 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=35.6407&lon=-118.4605&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: Fatal
- Injuries: 2 fatal, 1 serious
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 24434
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX85FA048
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/24434/pdf
- Page: https://openairdocs.org/ntsb/LAX85FA048

## Sequence of events

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

- In flight encounter with weather, climb - to cruise
  - weather condition - downdraft (contributing factor)
  - weather condition - windshear (contributing factor)
  - preflight planning/preparation - inadequate, pilot in command (cause)
  - judgment - disregarded, pilot in command (contributing factor)
- In flight collision with object, descent - uncontrolled
  - aircraft performance,climb capability - exceeded (cause)
  - altitude - not maintained, pilot in command (cause)
  - object - tree(s) (contributing factor)

## Analysis

ACFT DEPARTED ARPT IN MOUNTAIN VALLEY (ELEV 2,614) GENERALLY DIRECT TOWARD A SADDLE PASS (ELEV 6,500) ABOUT 1 MI NW & ON THE LEE SIDE OF THE VALLEY. TOPS OF THE MOUNTAINS AROUND THE VALLEY AVERAGE ABOUT 7,000 FT MSL. FLT ENCOUNTERED UPDRAFTS DURING CLIMB UNTIL REACHING 6,800 FT MSL NEAR THE PASS WHEN IT EXPERIENCED A STRONG DOWNDRAFT/WINDSHEAR. PLT STATED THAT ACFT WOULD NOT RESPOND TO EVEN FULL POWER APPLICATION & DESCENT COULD NOT BE ARRESTED PRIOR TO COLLIDING WITH TREES. NO WX BRIEFING WAS OBTAINED PRIOR TO FLT. STRONG WINDS ALOFT AT 6 & 9 THOUSAND FT WERE FORECAST, ALONG WITH DOWNDRAFTS, WINDSHEARS & MODERATE TURBULENCE IN MOUNTAIN AREAS.

## Aircraft

- Registration: [N9589V](https://openairdocs.org/deregistered/N9589V-1984-11-23), registration cancelled 1984-11-23, S/N 17264391, built 1974 (OpenAirDocs)
- Reported make and model: CESSNA 172M
- Registry model: [Cessna 172M](https://openairdocs.org/model/cessna-172m) (registry code 2072418) (OpenAirDocs)
- Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 17264391
- Airframe hours: 4525
- Engines: LYCOMING O-320-E2D 150 horsepower reciprocating
- Damage: Destroyed
- Flight: Personal, Part 91
- Registered owner: Donald Blankenship,Paul Aubin
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, November 1, 1984, 10 hours before
- Departed: L05, KERNVILLE, CA
- Destination: PTV, PORTERVILLE, CA
- Airport: L05, Kern Valley

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 64; private; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; seat: left; toxicology performed; flight hours: 276 total, 219 in this make and model, 193 as pilot in command, 31 in the last 90 days, 10 in the last 30 days, 2 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Visibility: 20 statute miles
- Lowest ceiling: none
- Temperature: 55 °F
- Altimeter: 30.00 inHg
- Observed at: BFL

## 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 19841123062999A](https://openairdocs.org/incident/19841123062999A), Nov 23, 1984: Cessna 172M, Lake Isabella, CA, Destroyed, 2 fatal. Struck trees after encountering downdraft in mountainous area. Turbulence and downdrafts forecast.

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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