Getting U-boats past Gibraltar

How could Germany distract Gibraltar's defenders and get U-boats out of the Mediterranean?

A submerged passage timed for a weaker current is the simplest option. Air attack or a surface diversion could provide cover, but an Italian bombardment would be costly.

Timing a submerged passage for a weaker current is the least elaborate option. An air attack on Gibraltar could cover the run, while an Italian bombardment would expose the fleet to heavy losses. A surface diversion from the Atlantic is also raised, with Scharnhorst approaching through the Bay of Biscay. Gibraltar therefore becomes a combined problem of currents, air cover, surface distraction, and acceptable loss.