Ten doors, and why a 747 needs them

Each side of the 747's main deck carries five big floor-level plug doors - ten Type A passenger exits in all. Later stretched-upper-deck models add their own exit pair up top, and a hatch over the cockpit gives the flight crew a path out.

Key facts
Main-deck doors	Five per side (1 through 5) - ten Type A exits
Slides	Slide/rafts at doors 1, 2, 4 and 5 each side; overwing slides for wing-area seats
Upper deck	The -300/-400 stretched upper deck adds its own exit pair
Crew escape	Flight-crew hatch over the cockpit

Certification limits a Type A exit (a floor-level opening of at least 42 × 72 in) to 110 seats. Ten of them is what lets a 747 legally carry 500 or more passengers.

Emergency hardware includes escape slides or slide/rafts on each side at doors 1, 2, 4 and 5, plus off-wing overwing escape slides for passengers seated near the wing - a configuration maintained from the 1969 original through the -2/300 stretch.

Why ten exits

A 747 was certified to carry far more people than any previous airliner, and that capacity is only legal because of exit count. Each floor-level Type A opening - at least 42 by 72 inches - is limited by certification to a certain number of seats, and the 747's ten main-deck doors plus overwing and upper-deck exits are what allow a 400-plus seat cabin to be certified at all.

The stretched upper deck on the -300 and later models added a second passenger deck with its own exits, which is part of why those variants could be certified for high-density layouts that the earlier types could not.

Escape hardware

Every passenger door on the type is armed with an inflatable slide, and slides at the outboard positions on each side are slide/rafts - a slide with an enclosed survival raft for over-water segments. The overwing exits get their own slides for the passengers seated over the wing. Off-wing slides are fitted because the wing is exactly where a door cannot be placed without interfering with the structure or the engines.

The cargo-loading system page covers the main-deck side cargo door, and the weight and balance manual determines which doors are used for the evacuation case.

Related

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