Casualties unknown

Aircraft Crash and Fire in Box Canyon (N7835P)

Grantsville, UT, US

On September 7, 1989, a Piper PA-24-180 (registration N7835P) operated by Calvin, Joe B. was involved in an aviation accident near Grantsville, UT. Investigators recorded the probable cause as: IMPROPER IN-FLIGHT PLANNING/DECISION BY THE PILOT, BY ENTERING A BOX CANYON WITH INSUFFICIENT ALTITUDE TO ASSURE A SAFE EXIT. CONTRIBUTING FACTORS WERE: BOX CANYON, RISING TERRAIN, AND HIGH DENSITY ALTITUDE. 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 pilot and passenger took off on a local flight at 1801 MDT. When the aircraft did not return, a search found it the next morning crashed and burned on the side of a box canyon. Investigation found no mechanical failure.

Accident Overview

A pilot and passenger departed on a local flight at 1801 MDT. The aircraft did not return, prompting a search. The following morning, searchers located the wreckage, which had crashed and burned on the side of a box canyon. The entrance to the canyon was from the southeast. The aircraft impacted steep terrain on the west side of the canyon, with impact marks indicating a southerly heading. Fragmented and gouged rocks were found approximately 50 feet upslope from where the main wreckage came to rest.

Wreckage Examination

Much of the wreckage was demolished by fire. Examination of the right wing revealed chordwise crushing of its lower skin. Both propeller blades were bent and twisted, with the tips torn off. Investigators found no evidence of preimpact mechanical part failure or malfunction. The density altitude at the crash site was approximately 7,000 feet.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001213X29339. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.