# NTSB MKC84LA206: Brantly Helicopter B-2, N4999C, Bennington, KS, July 8, 1984

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Limited investigation · Final report
- Date: July 8, 1984, 12:10 local (17:10 UTC)
- Place: Bennington, KS
- Coordinates: 39.030261, -97.590713 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=39.0303&lon=-97.5907&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: Minor injuries
- Injuries: 2 minor
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 33736
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=MKC84LA206
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/33736/pdf
- Page: https://openairdocs.org/ntsb/MKC84LA206

## Sequence of events

In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf).

- Loss of control - in flight, hover
  - proper altitude - not maintained, pilot in command (cause)
  - lack of total experience, pilot in command (cause)
  - directional control - not maintained, pilot in command (cause)
- In flight collision with terrain/water, hover
  - descent - not corrected, pilot in command (cause)
- Roll over, other

## Analysis

THE STUDENT PLT STATED THAT AFTER LIFTING TO A HOVER ON HER FIRST SOLO FLT, SHE MADE TWO 180 DEGREE HOVERING TURNS. SHE SAID THAT THE HELICOPTER ENTERED A VIOLENT LATERAL VIBRATION AND DESCENDED TO THE GROUND. EXAMINATION OF THE WRECKAGE DID NOT DISCLOSE ANY EVIDENCE OF PRE-IMPACT MALFUCTION OR FAILURE THAT WOULD HAVE CONTRIBUTED TO THE ACCIDENT.

## Aircraft

- Registration: N4999C (not matched to a registry record)
- Reported make and model: Brantly Helicopter B-2
- Category: Helicopter
- Airframe hours: 564
- Engines: LYCOMING VO-360-A1B 180 horsepower reciprocating
- Damage: Substantial damage
- Flight: Instructional, Part 91
- Operator: Larry Alderson
- Airworthiness certificate: Standard, Normal
- Departed: BENNINGTON, KS
- Airport: Berkley

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 32; student; medical: class 3, valid medical--w/ waivers/lim; seat: left; flight hours: 16 total, 16 in this make and model, 16 in the last 90 days, 16 in the last 30 days, 2 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 210° at 15 knots
- Visibility: 15 statute miles
- Lowest ceiling: none
- Temperature: 97 °F, dew point 68 °F
- Altimeter: 29.00 inHg
- Observed at: SLN, 16 nm away

## FAA reports on this event (1)

The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs).

- [Accident 19840708030819A](https://openairdocs.org/incident/19840708030819A), Jul 8, 1984: Hynes B2, Bennington, KS, Substantial damage. Student practicing hovering reported vibration. Rollover on sidewards ground impact. No malfunction found.

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

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