LAX91LA351
1991-08-07 · LODI, California, United States · Minor · 1 aircraft · Status: Completed
Aircraft involved
Probable cause & findings
THE INFLIGHT LOSS OF CONTROL BY THE PILOT FOR UNDETERMINED REASONS.
Factual narrative
IN HIS WRITTEN STATEMENT, THE PILOT SAID THAT SHORTLY AFTER LIFTOFF HE HEARD A LOUD BANG AND 'ALL DIRECTIONAL CONTROL WITH THE CYCLIC WAS LOST.' HE NOTED THAT THE HELICOPTER PITCHED SLIGHTLY TO THE RIGHT AND IMPACTED IN A CORN FIELD. THE HELICOPTER WAS EXAMINED IN DETAIL BY AN FAA AIRWORTHINESS INSPECTOR FROM THE OAKLAND, CALIFORNIA, FLIGHT STANDARDS DISTRICT OFFICE. ACCORDING TO THE INSPECTORS REPORT, HE IDENTIFIED NO MECHANICAL PROBLEMS WITH THE ENGINE, DRIVE TRAIN OR CONTROL SYSTEM. FUEL WAS FOUND IN THE TANKS, LINES AND THE CARBURETOR. HE SAID THAT HE FOUND NO EVIDENCE OF A SPRAY BOOM OR ROTOR BLADE STRIKE PRIOR TO GROUND IMPACT. THE INSPECTOR NOTED THAT THE GROUND CONTRACT MARKS WERE CONSISTENT WITH A NEARLY LEVEL ATTITUDE GROUND IMPACT, WITH ABOUT 70 FEET OF STRAIGHT GROUND SCARS. Source: NTSB Aviation Accident Database (Pre-2008 Archive) Retrieved: 2026-02-12
Verbatim from NTSB's published report. Source file
NTSB_1991_LAX91LA351.txt.
Findings + structured fields enriched from FAA avall.mdb.
Full investigation docket on
data.ntsb.gov ↗.
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Related research
Matched on aircraft type or causal vocabulary (loss of control). All research papers
- Embry-Riddle Scholarly Commons 2025 · Journal article (JAAER) A Scoping Review of Aviation Loss of Control Inflight Research
Loss of control – inflight (LOC-I) contributes to aircraft accidents at unacceptably high rates. Significant industry efforts and research have aimed to improve LOC-I prevention, detection, and recove…
- SKYbrary (Eurocontrol) 2024 · SKYbrary article Loss of Control In-Flight (LOC-I) — SKYbrary Knowledge Base
SKYbrary comprehensive knowledge-base entry on Loss of Control In-Flight — definitions, contributing factors, accident case studies (Air France 447, Colgan 3407), and prevention strategies.
- Semantic Scholar 2024 · Article (International Conference on Networking and Services) Risk Assessment of Loss of Control In-Flight Trajectories for Urban Air Mobility Safety
In Urban Air Mobility (UAM), maintaining a minimum separation between aircraft is a safety requirement, which becomes challenging amidst congested air traffic and off-nominal conditions, such as Loss …
- NTSB Aircraft Accident Reports 2022 · Accident report Loss of Control on Takeoff in Icing Conditions — Citation 560XL
Cessna Citation 560XL fatal takeoff icing accident, March 2018. Investigation of a Citation 560XL loss-of-control takeoff accident in icing conditions.
- Semantic Scholar 2021 · Article (Aviation) ANALYSIS OF GENERAL AVIATION FIXED-WING AIRCRAFT ACCIDENTS INVOLVING INFLIGHT LOSS OF CONTROL USING A STATE-BASED APPROACH
Inflight loss of control (LOC-I) is a significant cause of General Aviation (GA) fixed-wing aircraft accidents. The United States National Transportation Safety Board’s database provides a rich source…
- NASA NTRS 2021 · Presentation Use of Design of Experiments in Determining Neural Network Architectures for Loss of Control Detection
Abstract—We describe empirical methods for selecting a neural network architecture to implement belief state inference on generic commercial transport aircraft.