Casualties unknown

1991-05-07: Cessna 140 (N89828) — Walter L. Egbert — Ojai, CA

Ojai, CA, US

On May 7, 1991, a Cessna 140 (registration N89828) operated by Walter L. Egbert was involved in an aviation accident near Ojai, CA. Investigators recorded the probable cause as: The pilot's failure to maintain adequate airspeed during a go-around attempt in mountainous terrain with downdrafts, which resulted in the aircraft overflying the runway and colliding with a fence and dirt berm. 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 encountered severe downdrafts while approaching a destination airstrip in mountainous terrain. Attempting to abort the landing, the aircraft overflew the runway and struck a fence.

What happened

The aircraft was on final approach to a destination airstrip situated within mountainous terrain when it encountered significant atmospheric disturbances. The pilot reported experiencing turbulence along with downdrafts ranging from 500 to 1,500 feet per minute. Recognizing the deteriorating conditions, the pilot applied full engine power in an attempt to abort the landing and execute a go-around.

Despite the application of maximum thrust, the aircraft was unable to gain sufficient altitude or reverse its descent path effectively. The airplane overflew the departure end of the runway. As it continued forward beyond the paved surface, it collided with a fence and subsequently struck a dirt berm located near the perimeter of the airfield.

The investigation

The investigation focused on the operational environment and the pilot's actions during the critical phase of flight. Examination of the site confirmed the presence of mountainous terrain surrounding the airstrip, which is known to generate localized wind shear and downdrafts. The physical evidence at the impact site consisted of a fence and a dirt berm, consistent with the narrative provided by the pilot regarding the location of the final collision.

Findings

The primary factors contributing to the accident included the mountainous terrain which generated severe downdrafts. The pilot's decision to continue the approach into these conditions led to an inability to maintain safe flight parameters. Although full power was applied, the aircraft could not overcome the vertical wind components, resulting in an overflight of the runway and subsequent impact with ground obstacles.

Safety message

Pilots operating in mountainous areas must be aware of the potential for severe downdrafts and turbulence near airstrips. Understanding the limitations of aircraft performance in high-density altitude or turbulent conditions is critical when deciding whether to continue an approach or initiate a go-around early.

Probable cause

The pilot's failure to maintain adequate airspeed during a go-around attempt in mountainous terrain with downdrafts, which resulted in the aircraft overflying the runway and colliding with a fence and dirt berm.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001212X17036. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.