Flight Details
The pilot was conducting their third banner tow flight of the day. The first and second banner drops were completed successfully.
Incident Description
On the third banner drop, the pilot was unable to release the banner. The banner dragged along the ground and then entered the water of a nearby bay. The pilot reported that when the banner entered the water, the resultant drag was too great for the aircraft to overcome. The pilot was unable to sustain flight, and the airplane subsequently contacted the water.
The pilot stated that, unknown to them, the tow line used for the third flight was 50 to 75 feet longer than the lines used for the previous two flights.
Post-Accident Investigation
During the investigation, the tow release mechanism was actuated six times without a load, and it functioned properly on each actuation.