but when the london duck burst no flames, 28 passenger and the crew took an unexpected plunge into the tems. some swam for their lives, others clinging to the boat's sides, even as the blaze took hold. fortunately, rescue crews were on the scone in minutes and no one was seriously hurt. in june, there was another duck boat sinking. this one in liverpool. >> the commonally between the na majority of these accidents with these duck boats have been mechanical failure. >> in 2010, it was a stalled engine that left a philadelphia duck boat stranded in the delaware river. passengers helpless as a 250 foot barge plowed over their boat, dunk some three dozen of them no the murky water from the boat was tossing, just basically instead of jumping out, the boats kind of rolled over. we tumbled out. >> reporter: two young tourists would not macit out alive. another tragedy in known 99 in