The number of toilets on a Boeing 747 varies depending on the specific model and the airline's chosen cabin configuration, but most "Queen of the Skies" aircraft feature between 10 and 15 lavatories. For example, a high-capacity Boeing 747-400 operated by Lufthansa typically has 12 to 14 toilets strategically distributed across the main and upper decks. In a standard three-class layout, you will usually find two lavatories in the nose for First Class, four to five in the mid-section for Business Class, and six to eight in the rear for Economy. On the modern 747-8 Intercontinental, the upper deck usually houses two to three dedicated lavatories for Business Class passengers. The "passenger-to-toilet ratio" is an important design factor for long-haul comfort; on a fully loaded 747 with 400 passengers, a 14-toilet configuration results in roughly one restroom for every 28 passengers. These facilities utilize vacuum-flush technology to conserve water and are maintained by a complex plumbing system hidden within the fuselage, ensuring that even on 14-hour transoceanic flights, the sanitation needs of a small "flying city" are met efficiently and hygienically.