# NTSB ANC84LA034: Helio H-250, N5966X, Iliamna, AK, February 1, 1984

- Type: NTSB accident investigation
- Classification: Accident · Serious injuries · Limited investigation · Final report
- Date: February 1, 1984, 12:25 local (20:25 UTC)
- Place: Iliamna, AK
- Coordinates: 59.849769, -154.559661 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=59.8498&lon=-154.5597&mi=10
- Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping)
- Highest injury: Serious injuries
- Injuries: 1 serious
- Status: Completed
- Report: Approved by Office Director
- NTSB office: Alaska Regional Office
- NTSB case key (mKey): 4270
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC84LA034
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/4270/pdf
- Page: https://openairdocs.org/ntsb/ANC84LA034

## Analysis

ACCORDING TO WITNESSES, THE SKI EQUIPPED ACFT TOOK OFF TOWARD THE NORTH. THEY REPORTED THAT AFTER TAKING OFF, THE ACFT MADE A TIGHT LEFT TURN, THEN SPIRALED TO THE GROUND. THEY ESTIMATED THAT THE MAXIMUM ALT WAS APRX 150 FT. ALSO, THEY REPORTED THAT THE ENG WAS DEVELOPING FULL POWER UNTIL THE TIME OF IMPACT. THE 1229 ADT WINDS WERE FROM 010 DEG AT 19 GUSTING 27 KTS.

## Sequence of events

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

- Loss of control - in flight, takeoff - initial climb
  - weather condition - high wind (contributing factor)
  - weather condition - gusts (contributing factor)
  - maneuver - initiated, pilot in command
  - airspeed - inadequate, pilot in command (cause)
  - stall/spin - inadvertent, pilot in command (cause)
- In flight collision with terrain/water, descent - uncontrolled

## Aircraft

- Registration: [N5966X](https://openairdocs.org/deregistered/N5966X-2013-04-25), registration cancelled 2013-04-25, S/N 2529, built 1965 (OpenAirDocs)
- Reported make and model: HELIO H-250
- Registry model: [Helio H-250](https://openairdocs.org/model/helio-h-250) (registry code 4300302) (OpenAirDocs)
- Registry engine: [Lycoming 0-540 series](https://openairdocs.org/engine/lycoming-0-540-series) (registry code 41532, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 2529
- Engines: LYCOMING O-540-A1A5 250 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Registered owner: Joseph W. Terrell III
- Destination: 5NN, NONDALTON, AK
- Airport: ILI, Iliamna, runway 35, 4,800 × 150 ft, gravel

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 42; private; airplane ratings: single-engine land; medical: class 2, expired; seat: left

## Weather

- Conditions: Visual (VMC), Day
- Wind: 10° at 19 knots, gusting 27
- Visibility: 25 statute miles
- Lowest ceiling: 3,000 ft overcast
- Altimeter: 29.00 inHg
- Observed at: ILI

## 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 19840201040779A](https://openairdocs.org/incident/19840201040779A), Feb 1, 1984: Helio H250, Iliamna, AK, Substantial damage. Made a steep turn on climbout then spiraled into the ground. No current medical. Severe gusty winds in area.

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

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