This unlikely Boeing 747 model nicknamed the “ant eater” actually led to the final configuration of the 747. At first the 747 as considered a stop gap measure until the 1970s anticipated entry into service of the SST’s. Many believed that most 747s would be relegated to freighter service, replaced in passenger status by the SST thus the flight deck had to be clear of the main cargo deck. On this design, the flight deck below the passenger cabin was moved up and away above the passenger cabin.