The pilot reported that, during his preflight inspection of the Cessna T206, after a passenger had entered the airplane, he ensured that the right-rear cargo portion of the right cabin door was secure.
The right side cabin door was a two-piece forward passenger door and rearward cargo door combination, and was adjacent to the second row of passenger seats.
He did not close the right-front portion of the door because the passenger had secured that door multiple times before.
After completing the preflight inspection, he entered the airplane and observed the passenger close and latch the forward portion of the right door. He then saw the passenger, who was seated in the right rear passenger seat, struggling with the seatbelt that passed between the seat and the cargo door on the right. The pilot suggested the passenger switch seats, and the passenger moved to the left rear passenger seat and fastened his seat belt.
The pilot reported that, during the flight, while maneuvering and descending to 1,600 feet mean sea level, he banked to the left and heard a “brief whistle,” followed by a “loud boom sound.” He looked behind him and saw both portions of the right cabin door open. He returned to the airport in Porterville, California, without further incident.
The airplane sustained substantial damage to the fuselage.
Post-accident examination revealed red paint transfer on the forward portion of the door from the rear portion door latch and that both door sections could be opened if the latch for the rear door was open.
The pilot reported he believed that the right rear passenger seat belt “must have pulled on the door latch enough to dislodge it.”
He added that the red paint transfer was not there before the flight.
The pilot provided a post-accident examination video, which showed that he was able to use the larger airbag section of the seatbelt to wedge open the rear cargo door latch.
The “Rear Cargo Door Emergency Exit” placard in the airplane stated:
1. Open front cargo door as far as it will go.
2. Push rear door handle forward and force door open.
Probable Cause: The pilot’s failure to verify that the rear cargo portion of the right cabin door was adequately secured before flight, which resulted in both portions of the door opening in flight and substantial damage to the fuselage.
This experienced pilot with lots of make and model time inappropriately trusted the passenger to latch doors and secure belts. A similar seatbelt problem on a NYC helicopter flight turned off the fuel with a belt and six died; crazy, simple things cause big problems!
This April 2019 accident report is provided by the National Transportation Safety Board. Published as an educational tool, it is intended to help pilots learn from the misfortunes of others.
A bit of hurry (and not enough time) always seems to be an element in accidents also…