In 1944, Black Americans take pride in the exploits of the Black aviators known as the Tuskegee airmen. Their plane, the P-51 Mustang, is praised for its reliability and its performance in aerial combat. The development research for the Mustang was done at Langley, but workers there are constantly reminded not to talk about their jobs in public or even at home. If the people in town regard some of Langley’s engineers as “weirdos,” that is fine, so long as the townspeople do not learn details of what the weirdos actually do.

Langley conducts both actual flight tests of aircraft prototypes, in “free air,” and wind tunnel tests of models, in “compressed air.” The Sixteen-Foot High Speed Tunnel looms above the buildings of the West Area. Dorothy and the other computers study engineering physics and aerodynamics, to understand the calculations they are performing. All of the testing, plus the purely theoretical work of the “no-air” engineers, goes toward designing new or improved fighter, cargo, and bomber aircraft. When B-29s bomb Japan, Henry Reid tells the lab’s employees, from the engineers down to the cleaning staff, that they all had a part in the mission. Dorothy is helping to make a difference in the war’s outcome.