Boeing 737-600 vs. McDonnell Douglas DC-9-30

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 McDonnel Douglas DC-9-30, a narrow-body jet airliner first introduced in 1966, stands as a significant aircraft in the evolution of commercial aviation. Designed during an era of rapid growth in air travel, the DC-9-30 was developed to meet the demands of short to medium-haul routes, offering airlines a more efficient and practical alternative to the larger jetliners of the time. The Series 30 of the DC-9 included four main sub-variants, -31, -32, -33, and -34. During its production, the -30 was by far the most popular model of the DC-9 with 585 units delivered.

This aircraft was initially developed as the Douglas DC-9, prior to August 1967 merger with McDonnell Aircraft. The DC-9-30 measures in at 36.4 meters (119.3 feet) in length. This size enabled it to operate efficiently in smaller airports and on shorter runways - a niche that was underserved at the time of its introduction. Powered by a pair of Pratt & Whitney PWJTD engines, the DC-9-30 has a total thrust output of 134.0 kN (30,000 lbf). Its fuel capacity of 13,900 liters (3,672 US gallons) gives the DC-9-30 a range of approximately 2,800 kilometers (1,512 nautical miles). This range was particularly advantageous for airlines looking to serve regional networks with an efficient and reliable jet.

The DC-9-30's typical five abreast seating layout can fit around 115 passengers, with a maximum of 127 in a high-density layout.

In its market segment, the McDonnel Douglas DC-9-30 was a key competitor to other short-haul aircraft of the era. Its introduction provided airlines with a jetliner that was not only smaller and more versatile than the larger, long-haul aircraft but also more efficient and economical for short to medium-range routes.

Airlines such as Delta Air Lines, Eastern Air Lines, and TWA were prominent operators of the DC-9-30, utilizing its capabilities to enhance their regional route networks. The aircraft's role in these fleets demonstrated its effectiveness in bridging the gap between propeller-driven airliners and larger jets, contributing significantly to the growth of regional air travel.

The McDonnel Douglas DC-9-30's production and service history highlight its importance as a practical and versatile aircraft in commercial aviation. The last DC-9 to ever be built was delivered in 1982. After its retirement, McDonnell Douglas went on to produce the MD-80 and the MD-95.