The Boeing 737-400 is a narrow-body aircraft manufactured by Boeing, a commercial aircraft company from the United States. This aircraft has a maximum capacity of 188 passengers. Boeing 737-400 specifications: Length: 28.90 mHeight: 11.13 mEngine: 2 x CFM56-3B2 or 2 x CFM56-3C turbofansThe Boeing 737-400 is part of the 737 Classic Family, along with the 737-300 and 737-500. This aircraft was designed to fill the gap between the 737-300 and 757-200. The Boeing 737-400 has several features, including: Tail bumper to prevent tail scuffing during takeoffReinforced wing sparsThe Boeing 737-400 was replaced by the 737-800 in the Boeing 737 Next Generation family.