Norman Bel Geddes' "Airliner #4"

Having designed everything from household appliances to transcontinental
trains, Norman Bel Geddes turned his sights to the skies, creating in 1929
one of the most ambitious commercial airliner concepts ever put to paper: A
nine-story flying amphibious behemoth dubbed simply "Airliner #4." Inspired
by the Dornier DO-X flying boat, the aircraft -- designed in partnership
with Dr. Otto Koller -- would sleep 606 passengers in cruise liner-like
comfort. With a wingspan of 525 feet, the plane would have been twice the
size of Boeing 747.

Bel Geddes' plans were the fly his plane between Chicago and London via the
St. Lawrence Seaway with refueling done in flight over Canada (!). Although
he was purportedly in negotiations in a syndicate of Chicago businessmen to
fund the project, it never materialized, in no small part due to the Wall
Street crash and subsequent Great Depression.

Were this model available in 1/72 scale, its wingspan would be an incredible
87.5 inches, almost from floor to ceiling in an average house.