NTSB CAROL · Event
Event WPR21LA064
Aircraft involved
Probable cause & findings
A loss of directional control during the landing roll due to an undetermined failure of the tailwheel assembly.
Factual narrative
On November 03, 2020, about 1235 Pacific daylight time, a Stinson 108-3, N6855M, sustained substantial damage when it was involved in an accident in El Monte, California. The flight instructor and the pilot receiving instruction were not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 instructional flight. According to the flight instructor, the purpose of the flight was to provide tailwheel instruction to the private pilot. The pilot receiving instruction performed three full-stop takeoffs and landings from runway 19. During the landing roll following the fourth landing, the airplane began to veer to the left. The instructor assumed the flight controls and applied rudder, but the airplane did not respond. The instructor then applied right brake and the airplane began to turn to the right, but his subsequent application of left rudder produced no response. The airplane continued to turn to the right, and the left wing impacted the ground. The airplane came to rest facing the opposite direction and sustained substantial damage to the left wing and aileron. The airplane was equipped with a Scott 3000 series tailwheel assembly. The design incorporated a swiveling steering arm, that was connected to and controlled by the tailwheel steering yoke through a spring and a tension chain on both the left and right sides. The manufacturer’s instructions called for the spring to be connected directly to the tailwheel yoke, and the chain to be connected to the steering arm with a connector clip. Postaccident examination of the airplane revealed that both of the steering springs and chains had separated from both the tailwheel steering yoke and steering arm assembly and that the tension chain connector clips were connected to the tailwheel steering yoke rather than the steering arm. Both steering springs were located on the runway after the accident. One spring was recovered near the runway 19 centerline about 230 ft beyond the runway threshold, and the second was recovered from the safety area on the left side of the runway about 1,900 ft beyond the threshold. The left and right tension chains were not located. According to the airplane’s maintenance logbooks, the most recent annual inspection was completed 7 flight hours prior to the accident. During an instructional flight in the tailwheel-equipped airplane, the airplane veered left. Despite the instructor’s application of corrective control inputs, the airplane did not respond as expected, ultimately resulting in a ground loop and substantial damage to the left wing. Postaccident examination revealed that both of the airplane’s tailwheel steering springs and tension chains were missing. The springs were found on the runway following the accident, separated from each other by about 1,700 ft. Neither of the chains were located. The manufacturer’s instructions called for the spring to connect directly to the tailwheel yoke, and the chain to connect to the steering arm with a connector clip. Evidence suggests that the spring was instead incorrectly connected directly to the steering arm. This reverse installation, while not in compliance with the maintenance instructions, did not appear to functionally affect the operation of the steering system, and therefore without examination of the missing chains or further examination of the tailwheel assembly, the significance of this finding could not be determined. Source: NTSB Aviation Accident Database Retrieved: 2026-02-12
NTSB Findings
Hierarchical cause / factor breakdown from the FAA bulk avdata database. Each finding tagged C (Cause) or F (Factor).
- — Aircraft-Aircraft oper/perf/capability-Performance/control parameters-Directional control-Attain/maintain not possible
- — Not determined-Not determined-(general)-(general)-Unknown/Not determined
Verbatim from NTSB's published report. Source file
NTSB_2020_WPR21LA064.txt.
Findings + structured fields enriched from FAA avall.mdb.
Full investigation docket on
data.ntsb.gov ↗.
Beyond the agency record
Search this event elsewhere.
Pre-filled searches into the sources where news + community discussion of aviation events lives. External sources are reported, not agency. Treat them as signal that something happened, not as fact about what happened.
Entity-clustered aviation events in the press — last 24 hr + 30-day archive.
Official agency record + docket.
Investigative docket: factual reports, photos, transcripts.
Long-running aviation incident database (Flight Safety Foundation).
Community NTSB synthesis blog — often has photos and witness reports.
Gold-standard aviation incident blog.
Aviation industry news search.
GA pilot forum — informed but rumor-prone.
GA pilot subreddit search.
Tail-number page — flight history (free tier limited).
AOPA Air Safety Institute search.
Mainstream press coverage. Recent events only.
Privacy-preserving news search.
External links open in a new tab. We don't ingest their content; we deep-link search queries.
Related research
What the literature says.
Academic papers and agency reports matching this event's aircraft type or causal vocabulary (stall, maintenance). Sourced from NASA NTRS, NTSB Safety Studies, FAA CAMI, AOPA Air Safety Institute, Embry-Riddle Scholarly Commons, arXiv, and the Semantic Scholar academic graph.
- Embry-Riddle Scholarly Commons 2023 · Conference paper
The Value of Strong Partnerships to Build a Successful Aviation Maintenance Career Pathway Program for Transitioning Military Service Members
The aerospace industry is competing with other industries for a qualified workforce, and many of those competing industries are investing heavily in creating workforce development pipelines.
- Embry-Riddle Scholarly Commons 2026 · Journal article (IJAAA)
From Reactive to Predictive: A hybrid Trust-Mediated Adoption Framework for Data-Driven Maintenance in Distributed-Authority Aviation Environments
Modern aviation maintenance operates within increasingly data-intensive technological environments, yet the operational integration of predictive maintenance into routine decision-making remains incon…
- NASA NTRS 2026 · Conference Paper
Computational Analysis of Steady State Aerodynamics of Transonic Truss-Braced Wing Configuration in Deep Stall
This study presents a computational investigation of steady state aerodynamics of the Subsonic Ultra-Green Aircraft Research (SUGAR) Transonic Truss-Braced Wing (TTBW) configuration over a wide range …
- Semantic Scholar 2025 · Article (Applied Sciences)
Decision-Making Framework for Aviation Safety in Predictive Maintenance Strategies
The implementation of predictive maintenance (PM) in aviation presents unique challenges due to strict safety requirements, complex operational environments, and regulatory constraints.
- Embry-Riddle Scholarly Commons 2024 · Journal article (JAAER)
Low-Resource Automatic Speech Recognition Domain Adaptation – A Case-Study in Aviation Maintenance
With timeliness and efficiency being critical in the aviation maintenance industry, the need has been growing for smart technological solutions that optimize and streamline the different underlying ta…
- Embry-Riddle Scholarly Commons 2024 · Journal article (JAAER)
A New Trajectory in UAV Safety: Leveraging Reinforcement Learning for Distance Maintenance Under Wind Variations
In the field of aviation, safety is a critical cornerstone, and the operation of Unmanned Aerial Vehicle (UAV) systems is deeply connected with this principle.
Browse the full corpus — academia portal ↗