No fatalities

Ice Accumulation Leads to Stall During Forced Landing (N9316F)

Port Heiden, United States of AmericaLanding (descent or approach)

On January 30, 1998, a Cessna 208A Caravan (registration N9316F) operated by PenAir - Peninsula Airways - Alaska Airlines Commuter was involved in an aviation accident near Port Heiden, United States of America during landing or approach. No fatalities were reported. Investigators recorded the probable cause as: The pilot's inadequate in-flight decision resulting in airframe ice accumulation to the extent that degraded aircraft performance and insufficient airspeed occurred followed by a stall. Contributing factors were freezing rain and icing conditions. This summary draws on records from the Bureau of Aircraft Accidents Archives (B3A); 7 related events involving the same aircraft type or operator are linked below.

Sourcesthe Bureau of Aircraft Accidents Archives (B3A)Primary reportUpdated 2026-06-11Data APIEditorial standards
Aircraft registered N9316F
Aircraft registered N9316F. Photo: Aeroprints.com / CC BY-SA 3.0, via Wikimedia Commons

A pilot encountered freezing rain, leading to rapid ice accumulation. The aircraft could not maintain altitude, and during a forced landing attempt, the left wing stalled.

Departure and Weather

The pilot departed in visual meteorological conditions with visibility of three to four miles and high ceilings. The automated weather observing system (AWOS-3) at the airport was inoperative. The pilot did not have access to official weather prior to departure. The National Weather Service contracted observer made observations from a location about five miles south of the official weather station.

Encounter with Freezing Rain

While in cruise flight at 1,200 feet mean sea level, about five miles south of the airport, the airplane encountered freezing rain. The pilot reported rapid ice accumulation on the airframe, wings, and windshield. In an attempt to exit the icing conditions, the pilot initially changed altitude. As ice accumulation continued, the pilot elected to return to the airport.

Loss of Performance and Stall

While maneuvering to land, the airplane was unable to maintain altitude at full engine power. The pilot stated that any angle of bank resulted in the onset of pre-stall buffet. The pilot decided to land on a frozen lake south of the airport. The airplane did not reach the lake; the pilot reported that the airplane "mushed into the ground." During the flare and touchdown, the left wing stalled.

Post-Accident Examination

Examination of the airplane after the accident revealed a 1/2-inch layer of clear ice covering all upper and lower airfoil surfaces, from the leading edges to between one-third and one-half of the chord lengths. All antennas were coated with approximately 1/2 inch of clear ice. The airplane was not equipped with ice protection equipment except for pitot heat and windshield heat.

Probable cause

The pilot's inadequate in-flight decision resulting in airframe ice accumulation to the extent that degraded aircraft performance and insufficient airspeed occurred followed by a stall. Contributing factors were freezing rain and icing conditions.