Trijet design will almost always consume more fuel than a comparable twin engine design. This results in higher operating costs and reduced range. Although trij

Trijet design will almost always consume more fuel than a comparable twin engine design. This results in higher operating costs and reduced range. Although trijets are more efficient than four-engine aircraft, the difficulty and complexity of mounting the center engine through the tail will somewhat negate this advantage. quote from http://en.wikipedia.org/wiki/Trijet http://en.wikipedia.org/wiki/Trijet