Boeing 737-600 vs. Douglas DC-8

Launched in 1998, the Boeing 737-600 is the smallest aircraft in the 737 Next Generation (NG) series. It succeeded the 737-500, and was a significant evolution in Boeing's narrow-body offerings. It featured many upgraded features from the previous 737s, including aerodynamics, engines, and avionics. As the smallest NG variant, the 737-600 was designed for efficiency and adaptability, catering to airlines requiring a compact jet for short to medium-haul routes.

This aircraft extends 102.4 feet (31.2 meters) in length with a wingspan of 112.6 feet (34.3 meters). The 737-600, with a typical seating capacity for 123 passengers, offers an ideal balance between passenger comfort and efficiency, making it a fitting choice for airlines serving routes with moderate passenger demand. Equipped with two CFM International CFM56-7B20 engines, the 737-600 has a total thrust of 45,400 lbf (202.0 kN). This engine power, coupled with a fuel capacity of 6,868 US gallons (26,000 liters), gives the -600 a range of 3,051 nautical miles (5,650 kilometers). The 737-600 has a cruise speed of 528 mph (850 km/h) enabling airlines to maintain efficient and swift operations, particularly beneficial for regional network connections.

In the late 1990s and early 2000s, the Boeing 737-600 competed with aircraft such as the Airbus A318 and Bombardier CRJ series, offering airlines a modern alternative in the narrow-body market. Airlines including Scandinavian Airlines (SAS), Westjet, and Air Algerie operated the Boeing 737-600. Ultimately, the -600 variant was not a popular model of the 737 due to its economics. The -700, only slightly heavier, had a much greater payload. Additionally, the larger market was moving more towards higher capacity narrow-bodies with lower unit costs and greater revenue opportunities.

The Douglas DC-8, is a long-range, narrow-body jet airliner developed by American Douglas Aircraft Company. Introduced in the mid-1960s, the DC-8 was among the first generation of commercial jetliners, marking a significant transition in air travel from propeller-driven to jet-powered aircraft. This model was developed during a period of rapid advancement in aviation technology, driven by the growing demand for faster and more efficient air travel.

The DC-8's design features a length of 57.1 meters (187.3 feet), which, at the time of its introduction, was one of the longest for any airliner. This length, coupled with a wingspan of 45.2 meters (148.4 feet), reflects the aircraft's capacity to handle long-haul routes, a key requirement during the jet age's early years. The DC-8's size was a response to the airline industry's needs for greater passenger capacity and range. Equipped with four Pratt & Whitney JT3D turbojet engines, the DC-8 could achieve a total thrust of 320.0 kN (36,000 lbf). This power output was instrumental in enabling the aircraft to reach a range of approximately 5,900 kilometers (3,186 nautical miles), making it suitable for transcontinental and transatlantic routes. The DC-8's speed and range capabilities were significant advancements at the time, contributing to the reduction of travel times on international routes.

The cabin of the DC-8 was designed to seat around 220 passengers in a typical two-class configuration with six seats across. This capacity allowed airlines to transport more passengers per flight compared to earlier propeller-driven airliners, significantly increasing operational efficiency. The interior of the DC-8 was designed with comfort in mind, offering features that were considered state-of-the-art during its era.

In the commercial aviation market, the Douglas DC-8 competed with the other early quadjet, the Boeing 707. The introduction of the DC-8 was part of the broader trend towards jet-powered air travel, which revolutionized the airline industry by offering faster and more comfortable flights over longer distances. Airlines that operated the DC-8 were United Airlines, Delta Air Lines, Thai Airways, and Pan American World Airways. The DC-8's operational role was marked by its ability to serve long-haul routes with improved efficiency and speed, a factor that contributed significantly to the growth of global air travel during the 1960s and 1970s. The DC-8 was produced until 1972, with 556 aircraft built. As the model aged out, it was superseded by larger wide-body Douglas' DC-10 trijet.