Found and Explained Official on MSN

Boeing planned a twin-aisle 737 replacement with propfans that used 60% less fuel

The Boeing 7J7 was designed to replace aging 737s, 727s, and DC-9s with a 150-seat aircraft using rear-mounted ...

6 Cabin Designs Made Famous Pioneered By The Original Boeing 747 That Airlines Still Use Today

Many features we take for granted today.