success; but they also suffered very severely, more than half their number being lost.
As with the D Class, the E boats had twin screws. Their diesels developed 1600 hp which gave a surface speed, in service, of 14 knots. The submerged speed was 9.5 knots, produced by 840 hp electric motors. The radius of action of the E Class was 3000 miles on the surface at 10 knots and up to 65 miles submerged, at approximately 5 knots.
Although a large class, building over a number of years, the characteristics between the various groups within the class did not alter appreciably. Changes in form, dimensions and displacement were not sufficient to make any marked difference. in speed and endurance. However, as a result of war experience,
