Slayton had chosen the name Delta 7 for the spacecraft, as this would have been the fourth manned flight and Delta (Δ) is the fourth letter in the Greek alphabet.
Pokud by letěl, kabina by se jmenovala Delta 7, protože se jednalo o čtvrtý pilotovaný let a písmeno delta (Δ) je čtvrté v řecké abecedě.