Blackett's War

Blackett's War: The Men Who Defeated the Nazi U-Boats and Brought Science to the Art of Warfare, by Stephen Budiansky, Vintage, 2013. 

Operational Research

This book describes the origin of operational research in Britain during World War II. Blackett played a major role. Beforehand, civilian mathematicians, scientists and engineers had worked on only designing weapons, not analyzing how they were used. Operational Research contributed to winning the Battle of the Atlantic by reducing ability of German U-boats to sink Allie merchant marine.

Depth Charges

Blackett did important work on dropping depth charges to destroy German submarines. The OR people gathered statistics on the effectiveness of weapons versus various parameters such as the depth that the depth charges exploded at. Depth charges to sink submarines: closer to each other and shallower is better.

Merchant Ship Convoys

Operational research played a major role in using Navy military ships to protect convoys of merchant ships crossing the Atlantic from German U-boats. Blackett showed that larger convoys were better at protecting the merchant shipping.

Teaching the Americans a Thing or Two

The British taught these techniques to the Americans. Teaching techniques to Americans. In the United States Operational Research is called Operations Research.