A Fragment of Destiny - kindle book by Richard Turner

http://www.amazon.com/Fragment-Christopher-Sheppard-Adventure-ebook/dp/B00F0SCN66

In 1918, a German U-boat on a clandestine mission to the United States
vanishes at sea.

Ten years later, Christopher Sheppard finds himself thrust into a
deadly race to find the truth about the missing submarine and why
someone is willing to risk it all to stop him. Pursued from New York,
to Europe, to Greenland, and back to the US, Sheppard must keep one
step ahead of a man, blinded by grief, who will stop at nothing until
he has his revenge.