# NTSB NYC86LA239: Hiller UH12C, N73876, E.Conway, NH, September 22, 1986

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: September 22, 1986, 17:45 local (21:45 UTC)
- Place: E.Conway, NH
- Location: 44.0226° N, 71.0053° W: Placed by OpenAirDocs: center of East Conway, NH, within about 6 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=44.0226&lon=-71.0053&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report March 10, 1988
- Report: Approved by Office Director
- NTSB case key (mKey): 30423
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=NYC86LA239
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/30423/pdf
- Page: https://openairdocs.org/ntsb/NYC86LA239

## Sequence of events

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

- Loss of control - in flight, hover
  - aircraft handling - improper, pilot in command (cause)
- Hard landing, landing - flare/touchdown
  - proper climb rate - not maintained, pilot in command (cause)

## Analysis

PILOT LOST CONTROL OF THE HELICOPTER WHILE AT HOVER THEN DECIDED TO LAND. HOWEVER THE PILOT SET THE AIRCRAFT DOWN HARD. THE MAIN ROTOR BLADE SEVERED THE TAIL.

## Aircraft

- Registration: N73876 (not matched to a registry record)
- Reported make and model: HILLER UH12C
- Category: Helicopter
- Serial number: UH6003
- Airframe hours: 423
- Engines: FRANKLIN 210 210 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Registered owner: Richard H. Graves
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, September 17, 1984, 54 hours before

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 46; private; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; flight hours: 62 in this make and model, 20 in the last 90 days, 4 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Temperature: 64 °F

## 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 19860922045839A](https://openairdocs.org/incident/19860922045839A), Sep 22, 1986: Hiller UH12C, Conway, NH, Substantial damage. The helicopter lost rotor RPM on takeoff due to insufficient warm up. Copter landed hard. Rotor severed tail boom.

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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