Boeing 737-500 vs. McDonnell Douglas MD-11

The Boeing 737-500, introduced in 1987 as part of the 737 Classic series, is a narrow-body, twin-engine airliner designed for short to medium-haul routes. Recognized for its compact size and efficiency, the 737-500 catered to airlines needing a smaller capacity jet with the performance qualities of the larger 737 models.

At 101.7 feet (31.0 meters) in length and with a wingspan of 94.5 feet (28.8 meters), the 737-500 was adept at serving routes that required flexibility for airport size and range. This aircraft was particularly appealing to airlines for its ability to operate efficiently on shorter and less dense routes, providing a practical solution for smaller markets. While the -400 expanded on the -300, the -500 was actually constructed to considerably smaller than the -300. Comparatively, the 737-500 is closest in size and capacity to the 737-200. Powered by two CFM International CFM56-3C1 engines, the Boeing 737-500 has a total thrust capability of 40,000 lbf (178.0 kN). With a fuel capacity of 5,310 US gallons (20,100 liters), it boasts a range of 2,376 nautical miles (4,400 kilometers). The 737-500's cruise speed of 495 mph (796 km/h) contributed to its reputation as a reliable and efficient aircraft for regional travel.

In the commercial aviation landscape of its time, the Boeing 737-500 was a competitor to aircraft like the McDonnell Douglas MD-80 series. Its introduction provided airlines with a versatile option in the 737 family, bridging the gap between the larger 737 models and the need for a more economical, smaller jet. Southwest Airlines was the first customer of the -500, making their first flight in 1989. Lufthansa, United Airlines, and Continental also operated the Boeing 737-500. The aircraft played a significant role in these fleets, enabling the expansion of domestic and regional networks.

The Boeing 737-500 has faced accelerated retirement due to its smaller size. A majority of models were out of service after just 21 years in service. Most freight companies didn't even have interest in turning the -500 into a cargo jet. The 737-500 was replaced by the 737-600 of the Next Generation series.

The McDonnell Douglas MD-11 is a wide-body, tri-jet airliner, recognized for its extended range and enhanced capabilities in long-haul commercial aviation. As a successor to the iconic DC-10, the MD-11 incorporated advanced technology and design improvements, making it a significant model in the evolution of wide-body aircraft. The MD-11 took its maiden flight in 1990, and was produced until the turn of the 21st century. There are no MD-11s servicing passenger flights today, but some MD-11 are still being used for freight operations with FedEx, UPS, and Western Global Airlines.

With a length of 61.6 meters (202.1 feet), the MD-11 is notably longer than the DC-10, which provided increased passenger and cargo capacity. This extension in length was complemented by a wingspan of 52.0 meters (170.5 feet), which included winglets for improved aerodynamic efficiency. The MD-11's was equipped with GE CF6-80C2s or PW4000 turbofan engines, which delivered a total maximum thrust of 822.0 kN (123,000 lbf). With a substantial fuel capacity of 146,173 liters (38,615 US gallons), the MD-11 boasts a range of approximately 12,455 kilometers (6,725 nautical miles), enabling it to operate on intercontinental routes with ease.

The MD-11 comfortably accommodated 298 passengers, and could be designed to fit over 340 in a higher density configuration. The most common configurations for the twin aisle jet included 9 seats to a row (3-3-3 or 3-4-2).

In the competitive landscape of long-haul airliners, the McDonnell Douglas MD-11 was positioned as an alternative to models like the Boeing 747 and the Lockheed L-1011 TriStar. By 2004, most carriers that utilized the MD-11 for long-haul passenger routes had replaced it with the Airbus A330, A340, and Boeing 777. When Boeing acquired McDonnell Douglas in 1997, it ultimately created internal competition for the MD-11 with the 767 and 777. A lack of interest from the market also lead to Boeing cutting production for the commercial variant short, while the freight version was continued for slightly longer.

KLM, Swissair, and Delta Air Lines were among the airlines who utilized the aircraft's range and capacity to expand their international route offerings. The MD-11's operational role was characterized by its ability to efficiently serve long-haul routes, offering a blend of passenger comfort and operational economics. Some airlines like China Eastern Airlines and Korean Air had converted their MD-11 aircraft into freighters rather than selling or retiring them.

The MD-11's production and service history reflect its role as a pivotal model in the wide-body aircraft segment. Its design and technological advancements, including the use of winglets and a glass cockpit, marked important steps in the advancement of commercial aircraft design. Although its production was eventually surpassed by more modern aircraft, the MD-11 remains a notable aircraft in the history of aviation, particularly for its contributions to long-haul air travel.