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Atlas / NTSB / CEN10CA371

NTSB CAROL · Event

Event CEN10CA371

2010-07-04 East Troy, Wisconsin, United States Airport · 57C None 1 aircraft Status: Completed

Registry · N9011R

FAA Aircraft Registry record.

Make / Model

BRANTLY B-2B

TCDS

2H2 · BRANTLY INTERNATIONAL INC

Seats / Engines

2 seats · 1 engine

ADS-B equipped

Yes — Mode-S AC756E

Registrant of record

FRAUNDORFER STEVEN M

Source: FAA Aircraft Registry (releasable master file).

Aircraft involved

Probable cause & findings

The pilot's failure to maintain control during landing.

Factual narrative

Maintenance was performed on the aircraft’s fuel system and flight test was required. The pilot made a normal takeoff with a right hand traffic pattern. A normal approach was performed with a go-around. A second right pattern to runway 18 was performed. The pilot performed a straight-in auto-rotation for a rotor RPM check. He stated that he flared at 25 feet above the ground, leveled at 5 feet with the “(power off),” and then performed a hovering auto-rotation where both skids contacted the ground with zero forward airspeed and a heading was maintained. The pilot noticed the engine RPM began to rapidly increase and he rolled the throttle completely off and lowered collective. He reported that the left skid was coming off the ground and he applied full left cyclic and full down collective. The aircraft teetered with the left skid approximately four to six inches above ground and the aircraft continued to roll right. The pilot stated, “I believe the maneuver was performed successfully and either a strong wind gust or mechanical defect caused the roll over.” The pilot subsequently stated that the helicopter had an articulated landing gear system. He said that the struts travel approximately seven to eight inches and “if only one side retracts it causes a ‘rolling moment’.” About 22 minutes before the accident, the recorded winds about seven nautical miles and 155 degrees from the accident site were 200 degrees at 14 knots with gusts to 32 knots. An examination of the accident helicopter’s controls and landing gear revealed no anomalies. The helicopter pilot performed a straight-in autorotation to runway 18 for a rotor rpm check. The engine rpm began to rapidly increase and the pilot rolled the throttle completely off and lowered collective. He reported that the left skid was coming off the ground and he applied full left cyclic and full down collective. The aircraft teetered and continued to roll right. The pilot stated that the helicopter had an articulated landing gear system. He said that the struts travel approximately seven to eight inches and “if only one side retracts it causes a ‘rolling moment’.” About 22 minutes before the accident, the recorded winds about seven nautical miles and 155 degrees from the accident site were 200 degrees at 14 knots with gusts to 32 knots. An examination of the accident helicopter’s controls and landing gear revealed no preexisting anomalies. 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).

  • C Personnel issues-Task performance-Use of equip/info-Aircraft control-Pilot - C
  • Environmental issues-Conditions/weather/phenomena-Wind-Gusts-Not specified
  • Environmental issues-Conditions/weather/phenomena-Wind-Crosswind-Not specified

Verbatim from NTSB's published report. Source file NTSB_2010_CEN10CA371.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 (go-around, 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.

Browse the full corpus — academia portal ↗