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October 5, 2024 · Cessna 180 · N4631U

Big Lake, AK

Overview

Report Status
Factual report
Event Type
Accident
Date
October 5, 2024
Injury Outcomes
2 injuries (1 fatality, 1 serious injury)
Location
Big Lake, AK
Aircraft
Cessna 180 (1963)
Tail Number
N4631U
Injuries
Fatal
Aircraft Damage
Substantial
NTSB Number
ANC25FA001

On October 4, 2024, about 1730 Alaska daylight time, a float-equipped Cessna 180 airplane, N4631U, sustained substantial damage when it was involved in an accident near Big Lake, Alaska. The pilot was fatally injured, and one passenger sustained serious injuries. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 flight. According to the passenger, the airplane was departing from East Butterfly Lake, near Big Lake for a return flight to the Lake Hood Seaplane Base (LHD), Anchorage, Alaska. The passenger reported that just before starting their northerly takeoff run, strong, gusty, variable wind conditions prevailed. During takeoff from the lake, as the airplane passed low over an area of tree-covered terrain, a sudden gust of wind pushed the airplane towards the trees. The airplane’s right wing subsequently collided with a stand of tall trees, and the airplane came to rest inverted in the lake, partially submerged (See figure 1). Figure 1. Accident airplane, N4631U, at the accident site. (Alaska State Trooper Photo) A detailed wreckage examination is pending after the airplane is recovered from the waters of East Butterfly Lake.

Full Narrative

On October 4, 2024, about 1730 Alaska daylight time, a float-equipped Cessna 180 airplane, N4631U, sustained substantial damage when it was involved in an accident near Big Lake, Alaska. The pilot was fatally injured, and one passenger sustained serious injuries. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 flight. According to the passenger, the airplane was departing from East Butterfly Lake, near Big Lake for a return flight to the Lake Hood Seaplane Base (LHD), Anchorage, Alaska. The passenger reported that just before starting their northerly takeoff run, strong, gusty, variable wind conditions prevailed. During takeoff from the lake, as the airplane passed low over an area of tree-covered terrain, a sudden gust of wind pushed the airplane towards the trees. The airplane’s right wing subsequently collided with a stand of tall trees, and the airplane came to rest inverted in the lake, partially submerged (See figure 1). Figure 1. Accident airplane, N4631U, at the accident site. (Alaska State Trooper Photo) A detailed wreckage examination is pending after the airplane is recovered from the waters of East Butterfly Lake.

Flight

Event TypeAccident
Event Time17:30 AKDT
Nearest Airport0nm
Aircraft FireNo
Aircraft ExplosionNo

Aircraft

AircraftCessna 180
Tail NumberN4631U
Aircraft CategoryAir
DamageSubstantial
Operating RulePart 91
Engines1
Seats6

People & Injuries

Injury Summary2 injuries (1 fatality, 1 serious injury)
Fatal1
Serious1
Minor0
Uninjured0
Total2

Conditions

ConditionsVMC
LightDaylight
Wind90° @ 15 kt, gusting 28 kt
Visibility10 sm
CeilingNone
Temperature / Dew Point48 F / 32 F
Altimeter29.07 inHg
Observation Time17:56
Weather SourcePILO

Appendix: Source Data