In the opening phases of World War II, our country was feverishly training pilots for war. Thousands of cadets earned coveted US Army Air Corps wings. Six months later, half were dead. Investigation revealed that deaths attributable to VFR into IMC far exceeded combat losses. IMC was more dangerous than the enemy.
Realizing this, the Air Corps strengthened its instrument training program. Beyond needle-ball-and-airspeed, students had to learn the attitude and heading indicators, compass, and clock and fuse them into what became attitude instrument flying. To stimulate the development of a composite scan, they developed Patterns A, B, and the vertical S.
