Casualties unknown

Unregistered Experimental Aircraft Crashes After Steep Spiral Turn (N4713A)

Sanona Creek, AK, US

On September 2, 1993, a Piper PA-18A-150 (registration N4713A) operated by Garfield, Wade E. was involved in an aviation accident near Sanona Creek, AK. Investigators recorded the probable cause as: THE PILOT'S FAILURE TO MAINTAIN FLYING SPEED DURING A DOWNWIND TURN FOR LANDING. FACTORS CONTRIBUTING TO THE ACCIDENT WERE: THE OVERWEIGHT CONDITION OF THE AIRPLANE, AND FAILURE TO ASSURE THAT THE AIRPLANE COMPLIED WITH ALL APPLICABLE AIRWORTHINESS… This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.

Sourcesthe U.S. National Transportation Safety Board (NTSB) historical archivePrimary reportUpdated 2026-06-10Data APIEditorial standards

An unregistered airplane with balloon tundra tires and without required documentation crashed after a steep spiral turn. The aircraft was at least 117 lbs over max gross weight and lacked shoulder harnesses.

Accident Overview

The unregistered airplane was observed flying over the airstrip from the southwest at an altitude of 200-300 feet above ground level. It then initiated a left turn, intended as a base turn toward the west threshold of the airstrip. The turn progressed into a steep spiral descent, and the airplane impacted the ground in a near-vertical attitude.

Environmental Conditions

At the time of the accident, the wind was from the west at approximately 30 miles per hour.

Aircraft Configuration

The airplane was equipped with 32x15 balloon tundra tires. The source states there is no data relating to an evaluation of the airplane's flight performance and handling envelope with these tires installed.

Documentation Status

The airplane had no registration, flight manual, weight and balance record, or FAA Form 337 for its complete rebuild after it was reported destroyed in 1989. Additionally, there were insufficient Supplemental Type Certificates (STC) or FAA field approval documents for modifications.

Weight and Safety Equipment

The airplane was at least 117 pounds over its maximum gross weight. Shoulder harnesses were not installed.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001211X13278. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.