NTSB CAROL · Event
Event CHI85FA210
Registry · N404Z
FAA Aircraft Registry record.
Make / Model
ZENITH CH750
Year of manufacture
2025
Engine
LYCOMING O-235-C1 (115 hp)
Seats / Engines
2 seats · 1 engine
Last airworthiness date
20250902
ADS-B equipped
Yes — Mode-S A4BDBC
Registrant of record
MUEHLBERG STEPHEN E
Source: FAA Aircraft Registry (releasable master file).
Aircraft involved
Factual narrative
THE HELICOPTER EXPERIENCED EXTREME VERTICAL VIBRATIONS WHILE LANDING FROM A HOVER. INADVERTENT GROUND CONTACT DURING UNCONTROLLED OSCILLATIONS RESULTED IN DESTRUCTION OF THE HELICOPTER. Source: NTSB Aviation Accident Database (Pre-2008 Archive) Retrieved: 2026-02-12
Verbatim from NTSB's published report. Source file
NTSB_1985_CHI85FA210.txt.
Findings + structured fields enriched from FAA avall.mdb.
Full investigation docket on
data.ntsb.gov ↗.
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Related research
What the literature says.
Academic papers and agency reports matching this event's aircraft type. Sourced from NASA NTRS, NTSB Safety Studies, FAA CAMI, AOPA Air Safety Institute, Embry-Riddle Scholarly Commons, arXiv, and the Semantic Scholar academic graph.
- NASA NTRS 2019 · Reprint (Version printed in journal)
Deep stall characteristics of MU-300
The deep stall characteristics of the MU-300 Diamond aircraft are described. The MU-300 obtained type certification from the FAA in 1981, and from Canada, West Germany, and England in 1983.
- NASA NTRS 2019 · Technical Memorandum (TM)
Reporter Concerns in 300 Mode-Related Incident Reports from NASA's Aviation Safety Reporting System
A model has been developed which represents prominent reporter concerns expressed in the narratives of 300 mode-related incident reports from NASA's Aviation Safety Reporting System (ASRS).
- NTSB Aircraft Accident Reports 2021 · Accident report
Crash of Atlas Air Flight 3591, Boeing 767-300 (N1217A)
Atlas Air 3591 crashed into Trinity Bay, Texas, February 23, 2019. Investigation of the in-flight loss-of-control crash of Atlas Air 3591 into Trinity Bay, Texas.
- NASA NTRS 2014 · Presentation
300 FT Runway Visual Range (RVR) Experiment Review
- arXiv 2025 · arXiv preprint
A zero-dimensional global conservation model to determine non-ideal nozzle conditions for gas injections
To reduce computation times of simulations involving gas fueled internal combustion engines (ICEs), a model is developed that determines non-ideal nozzle exit conditions to spare expensive simulations…
- NASA NTRS 2025 · Abstract
LEO to GEO Communications from Concept to On Orbit Mission Success
NOAA (National Oceanic and Atmospheric Administration) and the NOW (Nano Orbital Workshop) project at NASA Ames Research Center collaborated to prove that the GOES satellites can communicate with spac…
Browse the full corpus — academia portal ↗