Cessna 180

Full Narrative

On July 5, 2020, about 1115 Alaska daylight time, a Cessna 180C airplane, N9185T, sustained substantial damage when it was involved in an accident near Anchorage, Alaska. The private pilot and one passenger were not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight.
According to the pilot, they were returning from a remote lake to Lake Hood Airport (PALH) in the float-equipped airplane. The pilot stated that the departure was normal, with about 10 to 12 mph of wind on the lake, creating a light chop on the water's surface. Upon touchdown at PALH, the left float dug into the water and the airplane veered abruptly and nosed over. He stated that they quickly exited the sinking wreckage.
A video captured the accident sequence and revealed that the airplane touched down on about the step of the floats before abruptly veering to the left. The right wing contacted the water and the airplane veered back to the right, and then to the left, before the airplane nosed over.
A postaccident examination of the left float revealed a large hole in the bottom of the float just forward of the step. (See Figure 1.) Corrosion was present around the hole and no impact signatures were present on the bottom of the float.

Figure 1 - Accident airplane at accident site, hole visible in left float. Photo courtesy of KTVA.