The 15 amphibious Ride The Ducks vehicles licensed for operations on the Delaware River are undergoing mechanical inspections and testing on the water, the Georgia-based company said.
"We're anxious to resume, but we are still working with the Coast Guard and trying to work through what we need to do to get them back in operation," spokesman Bob Salmon said.
Sixteen-year-old Dora Schwendtner and 20-year-old Szabolcs Prem were killed July 7 when a 250-foot-long barge being pushed by a tug slammed into the stalled duck boat, plunging 35 passengers and two crew members into the river.
New York City attorney Holly Ostrov Ronai and Philadelphia attorney Robert Mongeluzzi, who represent the families of the two victims, are citing a federal analysis of a 1999 accident in Arkansas in saying that the vessels are unsafe due to their design and canvas canopies.
The Coast Guard has not responded to that allegation, saying in a statement that it will work with the company and the city "to ensure that all safety issues related to the operation of these vessels are addressed."
The National Transportation Safety Board said that during the 1999 accident on Lake Hamilton in Arkansas, during the sinking of that duck boat - which was not operated by Ride the Ducks - "the natural buoyancy of passengers' bodies forced them into the overhead canopy, which acted like a net to entrap them and prevent their vertical escape."
The board recommended that the amphibious vehicles be required to install "reserve buoyancy," which could keep even a vessel swamped with water afloat.
Salmon, however, said the canopies on Ride the Ducks craft are designed to allow easy egress in the case of an accident. Although the Coast Guard requires at least a 32-inch opening between the side of a boat and the bottom of the canopy, the Philadelphia ducks have an opening of 42 inches, he said.
