Blood wings

From USAFA Folklore

Blood wings refers to a specific method of pinning on a fourth class cadet's first set of Prop and Wings at the conclusion of Recognition. The wings are placed upon the cadet's uniform, without the frogs (backings), then pounded into the cadet's chest such that the pins pierce the skin. If the pins are placed directly over the collarbone, the practice is especially painful. This is the same as the practice of the same name sometimes conducted with pilot wings at the conclusion of pilot training, or with jump wings at the end of Airborne School. Blood wings are officially banned at the Academy, but the practice still occurs from time to time.