Danger From Below Action filled story about flying, and salvage on lake Superior

This is an exciting story about T.J. and his crew first searching for lost German gold from WW-2. That venture literally blows up in their faces when their anchor snags an anti-ship mine causing it to explode, and damages their vessel. Back in port to get the boat repaired, they find about some fighter aircraft that landed on ice covered Lake Superior in a blinding storm at the end of the war. The aircraft landed successfully only to have the ice break, and the planes sink 300 feet to the bottom. There is one man left alive who was on that fateful mission, and thinks he knows where the very valuable aircraft are. This sets the crew in motion after getting their vessel back in service. The crew has to first fight off pirates that want to steal the gold that they were not able to find, then they have to deal with the sudden storms on the lakes, and a lot of other things to overcome.