# NTSB MKC84LA102: Hiller UH-12B, N1021Y, Ulysses, KS, March 15, 1984

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: March 15, 1984, 11:30 local (17:30 UTC)
- Place: Ulysses, KS
- Coordinates: 37.570793, -101.350135 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=37.5708&lon=-101.3501&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 33653
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=MKC84LA102
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/33653/pdf
- Page: https://openairdocs.org/ntsb/MKC84LA102

## Sequence of events

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

- Airframe/component/system failure/malfunction, cruise - normal
  - rotorcraft flight control,tail rotor pedal - vibration (cause)
  - maintenance,overhaul - inadequate, other maintenance personnel (cause)
  - rotor drive system,tail rotor gearbox(90 deg) - overload (cause)
  - rotor drive system,tail rotor gearbox(90 deg) - separation (cause)
- Hard landing, landing - flare/touchdown
  - terrain condition - open field (contributing factor)
  - precautionary landing - performed, pilot in command (contributing factor)
  - autorotation - improper, pilot in command (contributing factor)

## Analysis

THE PLT MADE AN AUTOROTATIVE PRECAUTIONARY LANDING AFTER FEELING VIBRATIONS IN THE ANTI-TORQUE PEDALS. THE ACFT WAS TURNED INTO THE WIND BUT LANDED HARD IN A FIELD. THE PLT UPON EXITING THE ACFT FOUND THE ANTI-TORQUE ROTOR AND GEARBOX MISSING. THEY WERE FOUND 100 YARDS AWAY, BACK ALONG THE FLT PATH. ANALYSIS OF THE FAILED PARTS REVEALED AN AREA OF FATIGUE IN THE ATTACHMENT FITTINGS OF THE ANTI-TORQUE ROTOR AND GEARBOX.

## Aircraft

- Registration: [N1021Y](https://openairdocs.org/deregistered/N1021Y-2019-07-18), registration cancelled 2019-07-18, S/N MH 353, built 1981 (OpenAirDocs)
- Reported make and model: HILLER UH-12B
- Registry model: [Hiller-Mitchell UH-12B](https://openairdocs.org/model/hiller-mitchell-uh-12b) (registry code 4360702) (OpenAirDocs)
- Registry engine: [Franklin 6V-335 series](https://openairdocs.org/engine/franklin-6v-335-series) (registry code 27039, reciprocating) (OpenAirDocs)
- Category: Helicopter
- Serial number: MH353
- Airframe hours: 1803
- Engines: FRANKLIN 6V4-200-C33 200 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Registered owner: Myers Helicopter Service
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, February 1, 1984, 5 hours before
- Departed: ULYSSES, KS

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 21; commercial; medical: class 2, valid medical--no waivers/lim.; seat: left; flight hours: 205 total, 47 in this make and model, 36 as pilot in command, 47 in the last 90 days

## Weather

- Conditions: Visual (VMC), Day
- Wind: 360° at 12 knots
- Visibility: 15 statute miles
- Lowest ceiling: none
- Temperature: 45 °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 19840315007069A](https://openairdocs.org/incident/19840315007069A), Mar 15, 1984: Hiller UH12B, Ulysses, KS, Substantial damage. Lost tail rotor control. Made hard autorotational landing. Gear box had separated. Fatigue break in attach fittings

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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