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Atlas / NTSB / ERA21LA390

NTSB CAROL · Event

Event ERA21LA390

2021-09-29 Kinston, North Carolina, United States Airport · KISO None 1 aircraft Status: Completed

Registry · N370NC

FAA Aircraft Registry record.

Make / Model

EUROCOPTER AS 350 B3

Year of manufacture

2008 · 13 years old at event

TCDS

H9EU · AIRBUS HELICOPTERS

Engine

TURBOMECA ARRIEL 2B1 (747 hp)

Seats / Engines

6 seats · 1 engine

Last airworthiness date

20080205

ADS-B equipped

Yes — Mode-S A434FA

Registrant of record

STATE OF NORTH CAROLINA

Source: FAA Aircraft Registry (releasable master file).

Aircraft involved

Probable cause & findings

The buckling of the tail boom as a result of a hard landing event of undetermined time and location.

Factual narrative

The pilot reported that he was on a pre-checkride flight and was conducting standard maneuvers as required by the commercial helicopter practical test standards. The flight was uneventful and lasted about an hour. He stated that, during the flight, “we had no hard landings or turbulence;” however, on the postflight checks he immediately noticed buckled metal on the tail boom near the fuselage attachment points. He said he noticed small dents on the bottom and sides of the tail boom when he first flew this helicopter in 2019; however, they were small and were checked pre- and postflight without signs of growth until this flight. An examination and review of the tail boom section by an Airbus representative and NTSB structural engineer noted wrinkled skin damage on the tail boom. Both Airbus and the NTSB agreed that this was very similar to cases in which the tail boom structure has been subjected to loads above the design load. As a result, the tail boom was permanently deformed and the structural strength was compromised, most likely from a hard landing event. The buckling of the lower portion of a semi-monocoque structure such as the tail boom is considered substantial damage since it adversely affects the structural strength and requires major repair or replacement. The exact time and date of the hard landing was not 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).

  • Organizational issues-Support/oversight/monitoring-Oversight-Equipment monitoring-Operator
  • Personnel issues-Action/decision-Action-Lack of action-Maintenance personnel
  • Personnel issues-Task performance-Use of equip/info-Aircraft control-Unknown/Not determined
  • Aircraft-Aircraft oper/perf/capability-Performance/control parameters-Landing flare-Not attained/maintained

Verbatim from NTSB's published report. Source file NTSB_2021_ERA21LA390.txt. Findings + structured fields enriched from FAA avall.mdb. Full investigation docket on data.ntsb.gov ↗.

Related research

What the literature says.

Academic papers and agency reports matching this event's aircraft type or causal vocabulary (turbulence). Sourced from NASA NTRS, NTSB Safety Studies, FAA CAMI, AOPA Air Safety Institute, Embry-Riddle Scholarly Commons, arXiv, and the Semantic Scholar academic graph.

Browse the full corpus — academia portal ↗