# NTSB NYC84LA070: Brantly Helicopter B-2B, N2273U, Mt. Pleasant, PA, February 12, 1984

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: February 12, 1984, 12:30 local (17:30 UTC)
- Place: Mt. Pleasant, PA
- Coordinates: 40.150875, -79.539649 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=40.1509&lon=-79.5396&mi=10
- Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 35491
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=NYC84LA070
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/35491/pdf
- Page: https://openairdocs.org/ntsb/NYC84LA070

## Sequence of events

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

- Loss of control - in flight, landing
  - fuselage - vibration (contributing factor)
  - reason for occurrence undetermined (cause)
  - diverted attention, pilot in command (contributing factor)
  - go-around - initiated, pilot in command
  - rotor rpm - not maintained, pilot in command (cause)
- Forced landing, descent - emergency
  - autorotation - initiated, pilot in command
- Hard landing, landing - flare/touchdown
- Other gear collapsed, landing - flare/touchdown
  - landing gear,skid assembly - overload

## Analysis

THE PLT FLEW TO GREENSBURG, WHERE HE BROUGHT THE HELICOPTER TO A 2 FT HOVER AND DEPARTED WITH A MAX PERFORMANCE CLIMB. HE STATED THE HELICOPTER BEGAN TO EXHIBIT CONTROL IRREGULARITIES WHICH HE DESCRIBED AS 'A DUTCH ROLL WOBBLE TYPE OF SHUFFLE.' HE CONTINUED THE FLT & SAID THE 'SHUFFLE' SUBSIDED AS PWR WAS REDUCED DURING APCH TO MT PLEASANT. HOWEVER, HE EXPERIENCED DIRECTIONAL CONTROL PROBLEMS DURING THE APCH WHICH WERE PROPORTIONAL TO CHANGES IN COLLECTIVE & THROTTLE APPLICATIONS. INITIALLY, HE THOUGHT THE PROBLEM WAS ASSOCIATED WITH THE WIND. THE PLT INCREASED THROTTLE, COLLECTIVE, RTPEDAL & BEGAN A CLIMB. THEN AS A PRECAUTION, HE CUT THE THROTTLE TO STOP AN INCREASING VIBRATION & KEEP THE ENG FROM OVERREVVING. COLLECTIVE WAS REDUCED TO MAINTAIN ROTOR RPM, THEN WAS INCREASED ON DESCENT THRU 20 FT AGL, BUT THE ACFT LANDED HARD, COLLAPSING A SKID. ACCORDING TO WITNESSES, IT HAD INSUFFICIENT PWR & MADE A 360 DEG ROTATION BEFORE IMPACT.TWO MAIN ROTOR BLADES SEPARATED AND WERE FOUND WITHIN PROXIMITY OF THE HELICOPTER WITH IMPACT DAMAGE.

## Aircraft

- Registration: [N2273U](https://openairdocs.org/deregistered/N2273U-2013-08-07), registration cancelled 2013-08-07, S/N 438, built 1964 (OpenAirDocs)
- Reported make and model: Brantly Helicopter B-2B
- Registry model: [Brantly B-2B](https://openairdocs.org/model/brantly-b-2b) (registry code 1440506) (OpenAirDocs)
- Registry engine: [Lycoming O&VO-360 series](https://openairdocs.org/engine/lycoming-o-vo-360-series) (registry code 41514, reciprocating) (OpenAirDocs)
- Category: Helicopter
- Serial number: 43A
- Airframe hours: 742
- Engines: LYCOMING IVO-360-A1A 180 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Edward Younkin
- Registered owner: Progressive Building Systems
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, May 31, 1983, 42 hours before
- Departed: 2G3, CONNELLSVILLE, PA

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 37; private; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; seat: right; flight hours: 194 total, 45 in this make and model, 115 as pilot in command, 23 in the last 90 days, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: calm
- Visibility: 20 statute miles
- Lowest ceiling: none
- Temperature: 63 °F, dew point -0 °F
- Altimeter: 30.00 inHg
- Observed at: LBE, 10 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 19840212051689A](https://openairdocs.org/incident/19840212051689A), Feb 12, 1984: Hynes B2B, Mt Pleasant, PA, Substantial damage. Lost control and rotor RPM during approach to a landing. Impact caused rotors to strike the muddy ground.

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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