Boeing 737-400 vs. Boeing 787-9

The Boeing 737-400, part of the 737 Classic series, is a narrow-body, twin-engine airliner developed to meet the evolving requirements of the short to medium-haul market. First introduced in 1988, the 737-400 expanded upon the success of its predecessor, the 737-300. The -400 variant entered manufacturing shortly after finalization of design plans between Boeing and launch customer Piedmont Airlines (later merged into US Airways). It gives increased capacity and range, offering an option in between Boeing's 737-300 and the 757-200.

The fuselage incorporated a key 8 foot expansion to enable typical accommodation for up to 170 passengers in a 2-class layout. Other changes included increased weights and structural reinforcements, enhanced avionics/flight controls, and higher thrust CFM powerplants required for the heavier max takeoff figures. Cost efficiencies were achieved keeping cockpit continuity with the ubiquitous 737 flight deck suite.

Spanning 119.6 feet (36.5 meters) in length with a wingspan of 94.5 feet (28.8 meters), the 737-400 was designed to accommodate the growing demand for larger single-aisle aircraft. The aircraft typically seats 144 passengers, providing more space and comfort compared to earlier models in the series. This increased capacity made the 737-400 an attractive option for airlines seeking to transport more passengers on popular routes, without the need for a larger, wide-body aircraft. Equipped with two CFM International CFM56-3C1 engines, the 737-400 delivers a total thrust of 44,000 lbf (196.0 kN). This engine configuration, combined with a fuel capacity of 5,310 US gallons (20,100 liters), allows the aircraft to achieve a range of 2,079 nautical miles (3,850 kilometers).

In the competitive commercial aviation market of its time, the Boeing 737-400 contended with models like the McDonnell Douglas MD-80 series. Its introduction marked another milestone for Boeing in the evolution of the 737 family, solidifying the company's position in the market for short to medium-haul airliners. Airlines such as Alaska Airlines, Turkish Airlines, and British Airways incorporated the Boeing 737-400 into their fleets. The aircraft's operational role was significant, enabling these carriers to expand their route networks and increase flight frequencies, particularly in domestic and regional markets.

The Boeing 787-9 is an extended variant of the 787 Dreamliner series, a family of wide-body, twin-engine jet airliners known for their fuel efficiency and range capabilities. First flown in 2013, the 787-9 was developed to provide additional seating capacity and range compared to its predecessor, the 787-8. This model caters to the needs of airlines for longer routes and increased passenger demand. Out of the 3 787 variants, the -9 is by far the best selling type. As of December 2023, there were 1113 Boeing 787s in airline service, comprising of 397 787-8s, 619 787-9s and 97 787-10s.

The 787-9 spans 62.8 meters (206.1 feet) in length, and 60.1 meters (197.2 feet) in wingspan. The aircraft's use of composite materials, making up a significant portion of its construction, contributes to its lighter weight and structural efficiency, leading to lower fuel consumption and reduced operational costs. Powered by two engine options, either the General Electric GEnx or the Rolls-Royce Trent 1000, the 787-9 delivers a total maximum thrust of 640.0 kN (142,000 lbf). These engines, combined with the aircraft's aerodynamic design, allow it to achieve a range of approximately 14,140 kilometers (7,635 nautical miles). This extended range makes the 787-9 suitable for a variety of long-haul international routes - such as Singapore to San Francisco, Auckland to New York, and Perth to London. These extreme long haul routes can have flight times north of 16 hours.

The aircraft typically accommodates around 290 passengers in a three-class configuration. The cabin features larger windows, higher humidity, and improved air pressure levels compared to traditional airliners. In the commercial aviation market, the Boeing 787-9 competes with other long-range wide-body aircraft such as Airbus' A350-900. Its introduction provided airlines with an option that blends efficiency, capacity, and range, making it a popular choice for various long-haul routes. Airlines that have incorporated the Boeing 787-9 into their fleets include All Nippon Airways, American Airlines, United Airlines, and Air New Zealand. These carriers utilize the aircraft's capabilities to efficiently serve a mix of high-demand routes, taking advantage of its operational efficiency and passenger appeal.

In summary, the Boeing 787-9 stands as a significant development in the Dreamliner series, offering enhanced capabilities in terms of passenger capacity and range. Its design and technological advancements represent an evolution in long-haul air travel, providing airlines with a versatile and efficient aircraft for their long-range operations.