1985-02-04: Beechcraft 80 Queen Air (N50NP) — North Pacific Airlines — Soldotna, United States of America

9 fatalitiesSoldotna, United States of AmericaLanding (descent or approach)

An NP flight 1802 aircraft crashed into trees during an approach to Soldotna after encountering heavy icing conditions and deteriorating weather.

What happened

While arriving at Soldotna, the crew of NP flight 1802 consulted with a local weather observer who reported calm winds, visibility between 8 and 10 miles, and a ceiling ranging from 600 to 800 feet. Following an initial missed NDB approach, the crew attempted a second approach. Shortly after, the crew notified the company that the aircraft had accumulated significant ice. Despite having the option to divert to Kenai for an ILS approach, the crew chose to attempt a VOR approach back to Soldotna.

During vectoring, the weather observer noted that conditions had dropped below landing minimums and suggested a diversion, though the crew did not acknowledge this warning. The aircraft subsequently struck trees in high terrain approximately 1.5 miles southeast of the airport. Evidence indicated the plane was in a circling pattern at the time of impact, an action that was not permitted south of runway 07/25. All nine occupants were killed in the accident.

Findings

Investigations into the crash identified several critical failures regarding equipment and maintenance. The aircraft anti-ice system was found to be inadequate; specifically, the single mode was non-functional and two de-ice boots were missing from the propeller blades. Furthermore, the company's maintenance practices were deemed insufficient.

Operational and environmental factors also contributed to the disaster. The local weather station lacked necessary visibility aids, featuring only one lighted marker and an inoperative ceilometer. It was noted that the FAA had not inspected the weather station in two years. Ultimately, the crash resulted from the crew flying into known adverse weather conditions while operating an aircraft with known mechanical deficiencies.

Probable cause

The accident was caused by the crew's decision to continue an approach into icing and low-visibility conditions while operating an aircraft with inoperative anti-ice systems.