Overall Trends
Total, fatal, and serious accidents in the selected range.
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
Search everything
Fast key and full-text search with live filters, watches, and precise metadata.
Use quotes for exact phrase matches (for example "fuel selector valve").
Featured 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…
High-signal investigations
Major cases, deep-report coverage, and investigation media across decades of NTSB history.
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 manufacturersAirports
More airportsOperators
More operatorsAbout
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
September 16, 1990 · Cessna 150D · N4183U
Park City, UT
Overview
Report Status
Probable Cause
Event Type
Accident
Date
September 16, 1990
Injury Outcomes
1 injury (1 serious injury)
Location
Park City, UT
Aircraft
Cessna 150D
Tail Number
N4183U
Operator
High Valley Aviation
Injuries
Serious
Aircraft Damage
Substantial
NTSB Number
SEA90LA187
THE STUDENT PILOT ENCOUNTERED STRONG UPDRAFTS AND DOWNDRAFTS WHEN CROSSING A RIDGE AT HIGH ALTITUDE IN THE VICINITY OF HIS FAMILY'S CABIN. DUE TO HIGH DENSITY ALTITUDE AND LACK OF CLIMB PERFORMANCE OF THE CESSNA 150D AT SUCH ALTITUDES, HE WAS UNABLE TO SUSTAIN ALTITUDE, AND CRASHED AT APPROXIMATELY 9000 FEET MSL.
NTSB Probable Cause
THE PILOT'S LACK OF UNDERSTANDING OF AIRCRAFT PERFORMANCE AND METEOROLOGICAL CONDITIONS WHEN FLYING AT HIGH DENSITY ALTITUDE IN CLOSE PROXIMITY TO MOUNTAINOUS TERRAIN.
Full Narrative
THE STUDENT PILOT ENCOUNTERED STRONG UPDRAFTS AND DOWNDRAFTS WHEN CROSSING A RIDGE AT HIGH ALTITUDE IN THE VICINITY OF HIS FAMILY'S CABIN. DUE TO HIGH DENSITY ALTITUDE AND LACK OF CLIMB PERFORMANCE OF THE CESSNA 150D AT SUCH ALTITUDES, HE WAS UNABLE TO SUSTAIN ALTITUDE, AND CRASHED AT APPROXIMATELY 9000 FEET MSL.
Flight
Event TypeAccident
Event Time09:30 MDT
Nearest Airport0nm N
Runway0
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftCessna 150D
Tail NumberN4183U
Aircraft CategoryAir
DamageSubstantial
OperatorHigh Valley Aviation
Operating RulePart 91
Engines1
Engine TypeReciprocating
Engine DetailsContinental · O-200A · Reciprocating · 100
Seats2
People & Injuries
Injury Summary1 injury (1 serious injury)
Fatal0
Serious1
Minor0
Uninjured0
Total1
Crew 1Age 23 · Third Class
Conditions
ConditionsVMC
LightDaylight
Wind270° @ 20 kt
Visibility50 sm
CeilingNone
Temperature / Dew Point0 C / 0 C
Altimeter0
Weather SourcePILO