On the surface and while travelling at ten knots the most common U-boat model of the time, the Type VII-C, had a range of nearly 8,000 miles. With six weeks’ worth of fuel, a single U-boat could roam the entire Atlantic span, from the panoramic beaches of France to the crags of the North American coastline. The radius of the war now spanned the ocean. There was no longer a safe spot where the convoy flock would be free from trouble. The gap had been closed.
