# NTSB ANC94LA027: Piper PA-18, N7121P, Port Alsworth, AK, December 23, 1993

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Limited investigation · Final report
- Date: December 23, 1993, 15:00 local (19:00 UTC)
- Place: Port Alsworth, AK
- Coordinates: 60.200111, -154.279556 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=60.2001&lon=-154.2796&mi=10
- Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping)
- Highest injury: Minor injuries
- Injuries: 1 minor
- Status: Completed, report August 17, 1994
- Report: Approved by Office Director
- NTSB office: Alaska Regional Office
- NTSB case key (mKey): 2481
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC94LA027
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/2481/pdf
- Page: https://openairdocs.org/ntsb/ANC94LA027

## Probable cause

THE PILOT-IN-COMMAND NOT MAINTAINING THE PROPER CLEARANCE FROM THE TERRAIN DURING THE APPROACH.

## Analysis

DURING AN APPROACH TO AN ICE FROZEN LAKE, THE PLANE, PILOTED BY A NON-CERTIFICATED PILOT, COLLIDED WITH A TREE.  IN AUGUST 1971, THE PILOT'S APPLICATION FOR A MEDICAL CERTIFICATE WAS DENIED BY THE FEDERAL AIR SURGEON.  THE PILOT REPORTED THAT FOR THE PAST TWENTY YEARS HE HAD BEEN TAKING AN ANTI-SEIZURE MEDICATION ON A DAILY BASIS WITHOUT ANY RECURRING PROBLEMS.

## Factual narrative

On December 23, 1993, at 1500 Alaska Standard Time, a wheel-ski equipped Piper PA-18 airplane, N7121P, collided with a tree and crashed during an approach to a frozen lake located about 3 miles southeast of Port Alsworth, Alaska.  The non certificated pilot-in-command, the sole occupant, received minor injuries, and the airplane was substantially damaged.  The local personal flight, operating under 14 CFR Part 91, departed Port Alsworth at 1430 and the intended destination was the frozen lake.  Visual meteorological conditions existed, and no flight plan was filed.

In August of 1971, the pilot's application for a medical certificate was denied by the Federal Air Surgeon.  The pilot reported that for the past twenty years he had been taking an anti-seizure medication on a daily basis without any recurring problems.

## Sequence of events

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

- In flight collision with object, approach - vfr pattern - final approach
  - object - tree(s)
  - clearance - not maintained, pilot in command (cause)

## Aircraft

- Registration: [N7121P](https://openairdocs.org/aircraft/N7121P), registered now, S/N 18-7121, built 1958 (OpenAirDocs)
- Reported make and model: Piper PA-18
- Registry model: [Piper PA-18-150](https://openairdocs.org/model/piper-pa-18-150) (registry code 7101828) (OpenAirDocs)
- Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 7121
- Airframe hours: 3590
- Engines: LYCOMING O-360 180 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Alsworth, John H.
- Registered owner: Alsworth, Joel J.
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, April 21, 1993, 77 hours before

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 41; medical: unknown; seat: front; flight hours: 400 total, 120 in this make and model, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: calm
- Visibility: 40 statute miles
- Lowest ceiling: 5,000 ft broken
- Temperature: 36 °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 19931223047229A](https://openairdocs.org/incident/19931223047229A), Dec 23, 1993: Piper PA18150, Port Alsworth, AK, Substantial damage. Collided with a tree trying to land on a frozen lake. No medical or ratings. Was taking anti siezure medication.

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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