A Cessna 208B Caravan was being operated for skydiving flights out Plant City-Blackwater Creek Ultralight Fligthpark (Florida, USA). After an uneventful mission, the aircraft approached Plant-City's Runway 35.
The aircraft in its final position (Source aviation-safety.net © FAA)
The weather was calm;
Wind - 80º at 6 knots
Clouds - none
QNH - 30.13 inHg
Visibility - 10 miles
According to the pilot, while on the final approach to runway 35 at an altitude of ~80 feet, the outside of the windshield became foggy. This prevented the pilot from seeing the runway. The pilot choose not to perform a go-around as the parachutist were in the vicinity of the field ad he did not want to take the risk of hitting them or hitting the trees surrounding the runway.
The pilot maintained the airplane's attitude, and with that heading and descent rate. When he felt the main gear had touched down, he applied reverse thrust. At that time he felt the nose landing gear collapsed, this resulted in the propellor striking the ground, bringing the aircraft to an abrupt stop. The National Transportation Safety Board investigated the accident, and as part of the investigation reviewed a video recording of the accident. It became apparent when reviewing the video that the nose landing gear touched down first, followed by the main landing gear. The aircraft bounced and the aircraft touched down a second time, again on the nose landing gear, which collapsed immediately. An inspection of the aircraft by an FAA inspector confirmed the separation of the nose landing gear, additionally substantial damage was found on the engine mounts and the nose section of the aircraft,
A review of the Pilot Operating Handbook (POH) indicated that the airplane was equipped with a defrost system for the forward cabin. According to the POH, the "push-pull control, labelled DEFROSTPULL, FWD CABIN-PUSH, is located on the cabin heat switch and control panel. With the control in the DEFROST position (pulled out), forward cabin air is directed to two defroster outlets located at the base of the windshield."
In their final report (published on the 28th of January 2021) the NTSB determined that the probable cause of the accident was;
"The pilot's improper landing flare due to reduced visibility from a foggy windshield and his failure to use the airplane’s windshield defrost system, which resulted in a hard landing and subsequent nose landing gear collapse."
The Final report as issued by the NTSB is available for reference by clicking on the file below;