Sitting up straight 4 bodies in a row. Lying down 4 heads and 4 pairs of feet in a row - arguably 8 x half people so 4 across again. On the other hand width wise the space is distributed among the top or bottom halves of 8 people and two aisles so one only gets an eighth of the available width per person. Really depends on if one wants to look at it as a glass half full or half empty I guess.