# NTSB LAX85LA351: Cessna 172P, N5259K, Saint Helena, CA, August 14, 1985

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: August 14, 1985, 16:30 local (23:30 UTC)
- Place: Saint Helena, CA
- Coordinates: 38.549163, -122.390609 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=38.5492&lon=-122.3906&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 3 uninjured
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 24802
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX85LA351
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/24802/pdf
- Page: https://openairdocs.org/ntsb/LAX85LA351

## Sequence of events

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

- Loss of engine power(partial) - mech failure/malf, cruise - normal
  - engine assembly,valve,intake - jammed (cause)
  - engine assembly,push rod - separation (cause)
- Forced landing, descent
  - terrain condition - none suitable (contributing factor)
  - go-around - not possible, pilot in command (cause)
- On ground/water collision with object, landing - roll
  - terrain condition - none suitable (contributing factor)
  - tree(s) (cause)
  - remedial action - not possible, pilot in command (cause)

## Analysis

DURING A LOCAL PERSONAL FLT, THE PLT SAID THE 'ENGINE BEGAN TO RUN ROUGH A SHAKE VIOLENTLY.' WITH NOT ENOUGH POWER TO MAINTAIN ALTITUDE, THE PLT ELECTED TO MAKE AN EMERGENCY LANDING IN A FIELD, HOWEVER, OVERRAN THE FIELD AFTER TOUCHDOWN AND COLLIDED WITH GROUND OBSTRUCTIONS IN A VINEYARD. EXAMINATION OF THE ENGINE REVEALED STUCK INTAKE AND EXHAUST VALVES IN THE NUMBER ONE CYLINDER. IN ADDITION, THE EXHAUST VALVE PUSHROD WAS FOUND SEPARATED IN THE MIDDLE WITH SEVERE BATTERING PEENING NOTED TO THE BROKEN ENDS OF THE PUSHROD.

## Aircraft

- Registration: [N5259K](https://openairdocs.org/deregistered/N5259K-2008-06-05), registration cancelled 2008-06-05, S/N 17274034, built 1980 (OpenAirDocs)
- Reported make and model: CESSNA 172P
- Registry model: [Cessna 172P](https://openairdocs.org/model/cessna-172p) (registry code 2072436) (OpenAirDocs)
- Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 17274034
- Airframe hours: 1449
- Engines: LYCOMING O-320-D2J 160 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Bridgeport Flying Service
- Registered owner: Juchau Family Trust
- Airworthiness certificate: Standard, Normal
- Last inspection: AAIP, July 22, 1985, 14 hours before
- Departed: APC, NAPA, CA

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 20; private; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; seat: left; flight hours: 74 total, 74 in this make and model, 40 as pilot in command, 2 in the last 90 days, 1 in the last 30 days, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 200° at 9 knots
- Visibility: 30 statute miles
- Lowest ceiling: none
- Temperature: 79 °F
- Altimeter: 29.00 inHg
- Observed at: APC, 23 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 19850814043219A](https://openairdocs.org/incident/19850814043219A), Aug 14, 1985: Cessna 172P, St Helena, CA, Substantial damage. Engine ran rough, lost power. Landed in a field, hit objects in a vineyard. NR1 cylinder valves frozen closed.

## Other investigations on N5259K (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 LAX87LA270](https://openairdocs.org/ntsb/LAX87LA270), Jul 11, 1987: Cessna 172P (N5259K), Grass Valley, CA, 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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