4 fatalities

1991-08-20: Britten-Norman Islander (N68HA) — Temsco Helicopters — Ketchikan, United States of America

Ketchikan, United States of AmericaFlight

On August 20, 1991, a Britten-Norman Islander (registration N68HA) operated by Temsco Helicopters was involved in an aviation accident near Ketchikan, United States of America in flight. 4 people were killed. Investigators recorded the probable cause as: The pilot attempted to maintain visual flight rules during instrument meteorological conditions, which, combined with obscuring weather and rising terrain, led to the collision. This summary draws on records from the Bureau of Aircraft Accidents Archives (B3A); 2 related events involving the same aircraft type or operator are linked below.

Sourcesthe Bureau of Aircraft Accidents Archives (B3A)Primary reportUpdated 1781211768Data APIEditorial standards

A commuter flight crashed into rising terrain near Ketchikan after the pilot attempted to fly in marginal weather conditions.

What happened

About 45 minutes after departing for Wrangell, Alaska, a scheduled commuter flight encountered deteriorating weather. While approximately 30 miles from Ketchikan, the pilot notified company dispatch of an intention to return to the departure point because of meteorological conditions. During this period, the pilot also spoke with another company aviator in the same area, and both described the local weather as marginal.

At the time of the accident, visibility at Ketchikan International Airport was reduced to 3 miles due to light rain, multiple cloud layers, and low ceilings. The aircraft type struck trees and rising terrain at an altitude of 800 feet MSL while traveling in a nearly level flight path toward the east southeast. Impact signatures on the right wingtip suggested the plane was in a very shallow right-wing-down and nose-up attitude when it first hit the trees. The accident resulted in four fatalities.

Findings

Investigations determined that the primary factor was the pilot's attempt to operate under visual flight rules (VFR) while encountering instrument meteorological conditions (IMC). Additional contributing elements included the presence of upsloping terrain within the flight path and weather conditions that obscured the ground from view.

Probable cause

The pilot attempted to maintain visual flight rules during instrument meteorological conditions, which, combined with obscuring weather and rising terrain, led to the collision.