Premium research interface

The modern interface for aviation safety intelligence.

Search investigations, review source evidence, monitor watched reports, and trace long-term patterns from one calm, data-first workspace.

63k+
Reports indexed
1940-2026
Coverage
Recent
Last data refresh
Featured Report

Loading…

Loading featured report…

Loading…
Open Report

Safety trends by operating rule

Track fatal and non-fatal accident patterns across Part 91, Part 135, and Part 121 operations.

Loading trend charts…

Browse the aviation graph

Move quickly by aircraft, airport, operator, and time with indexes built for research, not wandering.

Last Data Update

By Decade

By Month

Aircraft Manufacturer

More manufacturers

Airports

More airports

Operators

More operators

About

Aviation safety reports, made easier to study

NTSB Reports is an independent research and search tool for public aviation accident and incident records. It brings NTSB aviation reports, structured fields, docket files, extracted figures, photos, videos, and update history into one searchable interface.

The goal is practical safety education: make it faster to find relevant investigations, compare similar events, review factual records, and understand the evidence behind probable-cause and preliminary reports.

The investigative work and source records belong to the National Transportation Safety Board and the published investigation record. This site is not affiliated with or endorsed by the NTSB.

FAQs

NTSB Report

August 5, 1991 · Experimental RV4 · N835B

Napa, CA

Overview

Report Status
Probable Cause
Event Type
Accident
Date
August 5, 1991
Injury Outcomes
No injuries (2 uninjured)
Location
Napa, CA
Aircraft
Experimental RV4
Tail Number
N835B
Operator
Stephan D Barnes
Injuries
None
Aircraft Damage
Substantial
NTSB Number
LAX91LA347

THE PILOT SAID THE AIRCRAFT WAS IN CRUISE FLIGHT WHEN THE OIL PRESSURE SUDDENLY DROPPED. THE ENGINE BEGAN TO RUN ROUGH, THEN SEIZED ALTOGETHER. THE AIRCRAFT WAS CLOSE TO A PRIVATE AIRSTRIP AND THE PILOT WAS ATTEMPTING A FORCED LANDING ON THE AIRSTRIP. THE AIRCRAFT LANDED SHORT OF THE RUNWAY IN A GRAPE VINEYARD. RESPONDING SHERIFF'S DEPUTIES REPORTED THAT THE ENTIRE BELLY OF THE AIRCRAFT WAS HEAVILY COATED WITH OIL. FAA AIRWORTHINESS INSPECTORS EXAMINED THE AIRCRAFT AND FOUND THAT AN AUTOMOTIVE FRAM OIL FILTER WAS INSTALLED ON THE ENGINE, WITH SOME PLUMBING CHANGES. THE INSPECTOR STATED THAT THE OIL FILTER FAILED TO BYPASS OIL. THE OUTSIDE CASE OF THE FILTER WAS FOUND TO HAVE EXPANDED TO ABOUT 125 PERCENT OF NORMAL SIZE AND WAS LEAKING OIL.

NTSB Probable Cause

THE INSTALLATION OF A NON COMPATIABLE OIL FILTER AND SYSTEM PLUMBING CHANGES WHICH INDUCED THE OIL EXHAUSTION EVENT RESULTING IN A FORCED LANDING AND IN FLIGHT COLLISION WITH TERRAIN.

Full Narrative

THE PILOT SAID THE AIRCRAFT WAS IN CRUISE FLIGHT WHEN THE OIL PRESSURE SUDDENLY DROPPED. THE ENGINE BEGAN TO RUN ROUGH, THEN SEIZED ALTOGETHER. THE AIRCRAFT WAS CLOSE TO A PRIVATE AIRSTRIP AND THE PILOT WAS ATTEMPTING A FORCED LANDING ON THE AIRSTRIP. THE AIRCRAFT LANDED SHORT OF THE RUNWAY IN A GRAPE VINEYARD. RESPONDING SHERIFF'S DEPUTIES REPORTED THAT THE ENTIRE BELLY OF THE AIRCRAFT WAS HEAVILY COATED WITH OIL. FAA AIRWORTHINESS INSPECTORS EXAMINED THE AIRCRAFT AND FOUND THAT AN AUTOMOTIVE FRAM OIL FILTER WAS INSTALLED ON THE ENGINE, WITH SOME PLUMBING CHANGES. THE INSPECTOR STATED THAT THE OIL FILTER FAILED TO BYPASS OIL. THE OUTSIDE CASE OF THE FILTER WAS FOUND TO HAVE EXPANDED TO ABOUT 125 PERCENT OF NORMAL SIZE AND WAS LEAKING OIL.

Flight

Event TypeAccident
Event Time20:20 PDT
Nearest Airport0nm N
Runway0
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo

Aircraft

AircraftExperimental RV4
Tail NumberN835B
Aircraft CategoryAir
DamageSubstantial
OperatorStephan D Barnes
Operating RulePart 91
Engines1
Engine TypeReciprocating
Engine DetailsLycoming · O-320-B3B · Reciprocating · 160
Seats2

People & Injuries

Injury SummaryNo injuries (2 uninjured)
Fatal0
Serious0
Minor0
Uninjured2
Total2
Crew 1Age 41 · Third Class

Conditions

ConditionsVMC
LightDusk
WindCalm
Visibility50 sm
CeilingNone
Temperature / Dew Point0 C
Altimeter0
Weather SourcePILO

Appendix: Source Data