'S-35 is one of their diesel subs,' the technician with the cold said.

Most diesel subs have two or more diesel engines.

Battery operation is the only way a diesel sub can actually submerge.

The limits of battery technology severely constrain the amount of time a diesel sub can stay underwater.

Building a hundred high-tech diesel subs on spec, supposedly for export, then suddenly turning that inventory into a modern U-boat fleet.

Milgrom's people- every time- identified it as a neutral diesel sub, or a ship on the surface.

The eight new diesel subs are probably the most potent weapon the United States has agreed to sell.

Unlike nuclear-powered submarines, diesel subs cannot run submerged at high speeds for long periods.

But I don't know if we've got any diesel subs left in the fleet.

It was obvious to Carter that they had a diesel sub.