# NTSB LAX91LA410: Piper PA-28-161, N2520U, San Carlos, CA, September 27, 1991

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Limited investigation · Final report
- Date: September 27, 1991, 14:45 local (21:45 UTC)
- Place: San Carlos, CA
- Coordinates: 37.490989, -122.260566 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=37.4910&lon=-122.2606&mi=10
- Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping)
- Highest injury: Minor injuries
- Injuries: 2 minor
- Status: Completed, report May 26, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 27372
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX91LA410
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/27372/pdf
- Page: https://openairdocs.org/ntsb/LAX91LA410

## Probable cause

THE FAILURE OF THE NUMBER 3 INTAKE VALVE RESULTING IN A TOTAL LOSS OF ENGINE POWER.  A FACTOR IN THIS ACCIDENT WAS THE UNSUITABLE TERRAIN FOR LANDING THE AIRCRAFT.

## Sequence of events

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

- Loss of engine power(total) - mech failure/malf, takeoff - initial climb
  - engine assembly,valve,intake - failure,total (cause)
- Forced landing, descent - emergency
- On ground/water encounter with terrain/water, landing - flare/touchdown
  - terrain condition - soft (contributing factor)

## Analysis

THE PILOT REPORTED THAT THE AIRPLANE WAS BEING FLOWN FOR THE FIRST TIME SINCE REPLACEMENT OF SEVERAL MAJOR ENGINE COMPONENTS.  AFTER A SUCCESSFUL RUN-UP, THE AIRCRAFT DEPARTED THE AIRFIELD.  DURING THE INITIAL CLIMB AT ABOUT 100' AGL, THE ENGINE BEGAN TO RUN ROUGH AND THEN LOST TOTAL POWER. A FORCED LANDING WAS MADE TO A WET, MUDDY AREA.  THE AIRCRAFT CAME TO A SUDDEN STOP IN THE MUDDY AREA.  AN EXAMINATION BY AN FAA INSPECTOR DETERMINED THAT THE ENGINE'S NUMBER 3 INTAKE VALVE FAILED.  THE MODE OF FAILURE COULD NOT BE DETERMINED.

## Aircraft

- Registration: [N2520U](https://openairdocs.org/deregistered/N2520U-1992-12-01), registration cancelled 1992-12-01, S/N 288016028 (OpenAirDocs)
- Reported make and model: PIPER PA-28-161
- Registry model: [Piper PA-28-161](https://openairdocs.org/model/piper-pa-28-161) (registry code 7102803) (OpenAirDocs)
- Category: Airplane
- Serial number: 28-8016028
- Airframe hours: 5594
- Engines: LYCOMING O-320-D3G 160 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Donald Landen
- Registered owner: Donald Landen
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, September 9, 1991, 25 hours before

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 62; commercial; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; seat: left; flight hours: 1,527 total, 1,421 in this make and model, 1,452 as pilot in command, 55 in the last 90 days, 2 in the last 30 days

## Weather

- Conditions: Visual (VMC), Day
- Wind: 300° at 12 knots
- Visibility: 10 statute miles
- Lowest ceiling: none
- Temperature: 70 °F, dew point 55 °F
- Altimeter: 29.00 inHg
- Observed at: SQL, 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 19910927063269A](https://openairdocs.org/incident/19910927063269A), Sep 27, 1991: Piper PA28161, San Carlos, CA, Substantial damage. Engine lost power on climbout. Forced landed in muddy field. Intake valve had failed on freshly reworked engine.

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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