Aircraft interior lavatory

A method of providing an aircraft with more passenger seats in the aircraft's cabin, the method comprising the steps of:

• installing a combination of an enclosure unit and a passenger seat in the aircraft, said passenger seat having a seat back, a seat bottom, and a seat support that interfaces with the floor of the aircraft cabin and holds the seat bottom in an elevated position above the floor of the aircraft cabin, the combination comprising
• the passenger seat being configured to be located forward of and proximate to the enclosure unit,
• the enclosure unit being located aft of the passenger seat, the enclosure unit having
• a forward wall, said forward wall being part of an outer boundary defining a single enclosed space that includes a toilet, said forward wall being substantially not flat and configured to receive a portion of the exterior aft surface of the passenger seat back in an unreclined seat position,
• wherein said forward wall is adapted to provide more space forward of the enclosure unit such that the seat support can be positioned further aft in the cabin than if the cabin included another enclosure unit having a front wall that is substantially flat and is located in substantially the same position in the cabin as the forward wall,
• wherein said enclosed space is taller than the passenger seat,
• whereby said seat support is installed further aft in said cabin than would be possible if the substantially flat front wall of the other enclosure unit was located in substantially the same position in the aircraft cabin as the forward wall, and
• whereby a portion of the exterior aft surface of said passenger seat back in the unreclined seat position is received by said forward wall.