(Washington, DC)  --  Federal officials say mechanical problems and lack of federal oversight were major contributors to what caused the deadly crash involving a Ride the Ducks vehicle and a tour bus on Seattle's Aurora Bridge.  The crash killed five people aboard the bus and injured 69 other people.  The National Highway Traffic Safety Administration says the Duck vehicle went out of control on September 24th, 2015, because of a break in its front axle.  The agency says the Missouri-based maker of the amphibious vehicles was not registered as a vehicle manufacturer with the NTSB, accounting for the lack of safety oversight.