Ultramarine blue and Air Force yellow are the Air Force colors. Blue alludes to the sky, the primary theater of Air Force operations. Yellow refers to the sun and the excellence required of Air Force personnel. The winged horse, Pegasus, is symbolic of the rapid transport through the air as, on occasion, Pegasus carried heroic figures of Greek mythology from place to place "with the speed of the wind." The horse, which is universally accepted as a beast of burden, is also one of the most dignified and proud animals. The background of the disc represents the sky, and the cloud without base indicates the troop carrier mission of aerial movement through the sky anywhere on the globe. Special colors in this emblem signify that this squadron is known as the "Red Squadron" of the 315th Troop Carrier Group, Medium. The insignia was adopted in 1954, which was the Year of the Horse in the Japanese calendar system.