In 1985, Boeing began to design the 747-400. This type has a glass cockpit. This meant that only two people were needed in the cockpit. It also had new engines and a new cabin. The workers who made the 747-400 were not very experienced and Boeing wanted them to work for longer than they needed to. This meant that there were some problems with the first 747-400s. The −400 began being used by airlines in 1989.