The boat accident described below, resulting in the death of two occupants, presented the challenge of determining who of the four occupants of the boat was the driver at the time of the accident, and what was the seating position of each occupant.

To arrive to the basis for the final opinions, the author of this article developed an analysis combining basic engineering principles with detailed analysis of the injuries sustained by the occupants and anatomy of the human body, with emphasis in anatomy of the hand of the driver. Additionally, the cause of the accident was investigated.

Background of the Accident

In the early morning hours (approximately 2:20 a.m.) of July 10, 1988, an 18' speedboat collided with channel marker no. 11 located in New Pass Channel in Sarasota Bay in Florida, resulting in two deaths.

According to various witnesses, the boat was traveling at an estimated speed of 20 to 30 MPH.

The occupants of the boat at the time of the accident were a woman 29 years old, height: 66" = 5' - 6"; weight: 120-125 lbs; a 22 year old man, height: 74" = 6' - 2"; weight 180 - 190 lbs; a 21 year old man, height: 73.5" = 6' - 1 ½"; weight: 158 lbs; and a 20 year old man, weight: 145 lbs. All occupants received serious injuries and as a result of their injuries, two of the occupants died, one woman and one man.

Boat Description

The boat was a 1981 Rally Sport of fiberglass construction, powered by a 200 HP Evinrude outboard engine. It has independent-adjustable bucket seats for the driver and forward passenger and a bench seat across the transom for the two astern passengers.

The forward areas of the deck and bottom are primarily built with two fiberglass woven roving mats, having a layer of chopped fiberglass (chopped strand mat (CSM) between the gelcoat and the two woven rowing mats. There are no internal stringers, frames or longitudinal stiffeners. It appears that the only reinforcements were provided by a wooden core in the keel area and an extra chopped strand mat thickness in the areas of each spray rail.

The boat had a gasoline tank, located at centerline, just forward of the cockpit (measuring 33" in length, 16" in width and a depth varying between 8" to 12"), which is secured by a small bracket connecting the tank to the underside of the deck, and also restrained by the filling line.

The following is a weight estimate of the boat including passengers, fuel and miscellaneous equipment:

. . .Continue to read rest of article (PDF).