as the blueprints for this cluster of four rockets began to emerge from their drawing boards, the designers' nickname for their project gradually was adopted. since their first cross-section drawings showed four holes, they called the project "little joe," from the craps throw of a double deuce on the dice. although four smaller circles were added later to represent the addition of recruit rocket motors, the original name stuck. the appearance on engineering drawings of the four large stabilizing fins protruding from its airframe also helped to perpetuate the name little joe had acquired.