Designed to carry over 500 passengers, the MD-12 promised lower costs, improved efficiency, and a new era of long-haul travel. However, despite bold plans and high hopes, the project collapsed ...

In the early 1990s, McDonnell Douglas had an ambitious plan—to build a double-deck jumbo jet that could rival the Boeing 747 and Airbus’ future A380. Designed to carry over 500 passengers, the MD-12 ...