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

October 15, 1997 · Sego Tool HAWK H2X · N4412X

Tooele, UT

Overview

Report Status
Final with probable cause
Event Type
Accident
Date
October 15, 1997
Injury Outcomes
No injuries (1 uninjured)
Location
Tooele, UT
Aircraft
Sego Tool HAWK H2X
Tail Number
N4412X
Operator
Groen Brothers Aviation
Injuries
None
Aircraft Damage
Substantial
NTSB Number
FTW98LA015

According to the pilot, he was taking off for one of a series of flight tests. He reported that shortly after liftoff, the gyroplane made an uncommanded roll to the right. The pilot said that he applied full left cyclic and full left rudder, but the main rotor system struck the ground. The main rotor blades separated from the gyroplane and the aircraft came to rest with the fuselage twisted. Postcrash examination of the gyroplane by the design/manufacturing team revealed that the control system design of this aircraft had an inherent lag in time between control input and aircraft response. They found the runway that the gyroplane was taking off from sloped 1.7 to 1.8 degrees to the left. They said that 'the moment the aircraft left the ground, gravity moved the fuselage to the left and the rotor disk to the right.' Subsequently, a right turn was initiated and ground contact was made by the main rotor disk before the pilot's correction inputs could take effect.

NTSB Probable Cause

The pilot's failure to maintain aircraft control. Contributing was the inadequate design of the flight control systems, resulting in slow response to pilot input.

Full Narrative

On October 15, 1997, approximately 1416 mountain daylight time, a Sego Tool Hawk H2X gyroplane, N4412X, was substantially damaged when it impacted the ground during initial climb following takeoff near Tooele, Utah. The airline transport rated pilot, the sole occupant in the gyroplane, was not injured. The gyroplane was being operated by Geoen Brothers Aviation, Inc., under Title 14 CFR Part 91. Visual meteorological conditions prevailed for the local test flight that was originating at the time of the accident. No flight plan had been filed. According to the pilot, he was taking off for one of a series of flight tests. He reported that shortly after liftoff, the gyroplane made an uncommanded roll to the right. The pilot said that he applied full left cyclic and full left rudder, but the main rotor system struck the ground. The main rotor blades separated from the gyroplane and the aircraft came to rest with the fuselage twisted. Postcrash examination of the gyroplane by the design/manufacturing team revealed that the control system design of this aircraft had an inherent lag in time between control input and aircraft response. They found the runway that the gyroplane was taking off from slopped 1.7 to 1.8 degrees to the left. They said that "the moment the aircraft left the ground, gravity moved the fuselage to the left and the rotor disk to the right." Subsequently, a right turn was initiated and ground contact was made by the main rotor disk before the pilot's correction inputs could take effect.

Flight

Event TypeAccident
Event Time14:16 MDT
Nearest AirportTooele South Army Depot (0nm)
Runway36
Runway Length5000 ft
Runway Width100 ft
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo

Aircraft

AircraftSego Tool HAWK H2X
Tail NumberN4412X
Aircraft CategoryGyro
DamageSubstantial
OperatorGroen Brothers Aviation
Operating RulePart 91
Engines1
Engine TypeReciprocating
Engine DetailsChevrolet · V-8 · Reciprocating · 450
Seats2

People & Injuries

Injury SummaryNo injuries (1 uninjured)
Fatal0
Serious0
Minor0
Uninjured1
Total1
Crew 1Age 49 · Second Class

Conditions

ConditionsVMC
LightDaylight
Wind300° @ 8 kt
Visibility15 sm
CeilingNone
Temperature / Dew Point63 F / 37 C
Altimeter30.00 inHg
Observation Time20:52
Weather SourceWFAC

Appendix: Source Data