Casualties unknown

1995-06-17: Cessna P210N (N333HF) — William D. Henderson — Mammoth Lakes, CA

Mammoth Lakes, CA, US

On June 17, 1995, a Cessna P210N (registration N333HF) operated by William D. Henderson was involved in an aviation accident near Mammoth Lakes, CA. Investigators recorded the probable cause as: the pilot's continued flight into instrument meteorological conditions during dark nighttime over mountainous terrain; and his failure to maintain an adequate altitude to ensure terrain clearance. Thw weather and terrain were factors. 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 1781061362Data APIEditorial standards

A pilot on a night cross-country flight collided with terrain at 7,300 feet near a mountain campground after being briefed on variable weather including icing and mountain obscurement. No flight plan was filed; the pilot's medical certificate had expired.

Accident Overview

A pilot flying a single-engine airplane on a cross-country trip between Long Beach and Mammoth, California, collided with trees and terrain during a dark nighttime flight over high mountainous terrain. The accident occurred near a mountain campground at an approximate elevation of 7,300 feet above mean sea level.

Preflight and Weather

The pilot received four weather briefings prior to departure. The briefer informed the pilot of variable weather conditions, including mixed icing in clouds, mountain obscurement, and precipitation. At the accident site, witnesses estimated the ceiling to be about 200 feet above ground level, with snow falling.

Flight and Collision

No flight plan was filed for the flight. Witnesses near the campground heard the airplane approaching with its engine running before it collided with trees and terrain.

Pilot Background

The pilot's medical certificate had expired. The Federal Aviation Administration (FAA) had declined to issue the pilot another medical certificate because his diabetes was insufficiently controlled.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001207X03730. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.