Casualties unknown

Single-Engine Aircraft Crashes in Valley During Poor Weather (N755AA)

Riverton, UT, US

On December 9, 1992, a Beech 35-33 (registration N755AA) operated by Porter, Howard K. was involved in an aviation accident near Riverton, UT. Investigators recorded the probable cause as: TERRAIN CLEARANCE WAS NOT MAINTAINED. FACTORS TO THE ACCIDENT WERE: SNOW AND FLIGHT INTO KNOWN ADVERSE WEATHER. 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

A single-engine aircraft crashed in a valley about seven miles south of the airport. The pilot was aware of poor weather before departure, and post-crash investigation found no mechanical failure.

Incident Overview

A single-engine aircraft crashed along the west side of a valley near rolling hills, approximately seven miles south of the airport. According to the pilot's son, who was flying a twin-engine aircraft with another pilot, the father (the pilot of the single-engine plane) took off about eight minutes before their departure. The father turned toward the northwest, while the son turned to the northeast to follow the valley south.

Weather Conditions

The son reported that a weather front was running across the valley. Light snow was falling, and visibility was poor at the time. Prior to departing, the father was aware of the poor weather conditions along the route of flight.

Witness Account

A witness reported hearing the crash but could not see it due to the falling snow.

Investigation Findings

Post-crash investigation did not reveal evidence of a mechanical failure or malfunction. No other causal factors were identified.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001211X16237. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.