SEATTLE — Ride the Ducks Seattle is suing its parent company, saying the company knew about a defect in their amphibious vehicles but didn’t disclose it, which ultimately led to the deadly crash on the Aurora Bridge in 2015.

Ride the Ducks International (RTDI), based in Georgia, is the manufacturer of the Stretch Ducks, also known as the "Duck Boats" in Seattle. 

In 2003 and 2004, RTDI found the front axle housing on their Stretch Ducks contained a “weak point – a defect” and came up with their own fix for it, which involved welding a piece of metal or “a tab” to the weak point, according to the lawsuit filed this month by Ride the Ducks Seattle (RTDS). 

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RTDI never told buyers of their amphibious vehicles about the defect, nor did they report the problem to the National Highway Traffic Safety Administration, court documents said.

Later in 2004, RTDI sold a Stretch Duck with the alleged “defect” to Ride the Ducks Seattle (RTDS), without telling them about the problem, according to the lawsuit. RTDS continued to purchase more Stretch Ducks over the years from its parent company with no knowledge of the defects.

RTDI experienced two more front axle failures in 2013, both of which were on vehicles that had the “tab” remedy, according to the lawsuit. 

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It wasn’t until then that RTDI concluded the tab was not enough of a fix, however, the company still didn’t consult with engineers or notify officials, or inform Stretch Duck purchasers about the failures, the defect, or the tab’s insufficiency, the court document said. 

On September 24, 2015, RTDS was operating a Stretch Duck with the defect when the left front axle housing failed, causing the crash that killed five people and injured several others, according to the lawsuit. 

The National Transporation Safety Board investigated the crash and found that the duck boat involved didn't have the axle repair that was recommended in 2013. 

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The lawsuit claimed that because RTDI failed to ever notify purchasers about the defect, RTDS never knew about the needed fix for its amphibious vehicles.