Boeing 707-320 vs. Boeing 737-400

Introduced in 1957, the Boeing 707-320 is a significant aircraft in the history of commercial aviation, marking Boeing's venture into the jetliner market. As a narrow-body, long-range airliner, the 707-320 played a pivotal role in the jet age, revolutionizing air travel with its speed and range capabilities.

The 707-329 is 46.6 meters (152.9 feet) long, and 44.4 meters (145.7 feet) from wing tip to wing tip, making it one of the larger aircraft of its time. Its design accommodates a typical seating arrangement for 137 passengers. Equipped with four engines, the 707-320 delivers a total thrust of 340.0 kN (76,000 lbf). Its fuel capacity of 90,300 liters (23,855 US gallons) contributes to a range of 5,400 kilometers (2,916 nautical miles). With a cruise speed of 890 km/h (553 mph), the 707-320 was known for reducing travel times significantly compared to propeller-driven aircraft, making it popular for transatlantic routes. Its cockpit required three crew members: a pilot, copilot, and flight engineer.

In the commercial aviation sector, the Boeing 707-320 competed with aircraft like the Douglas DC-8. Its introduction was a major step forward for Boeing, establishing the company as a leader in the jetliner market. The 707-320's ability to cover long distances quickly and efficiently made it a preferred choice for airlines expanding their international operations. Airlines such as Pan American World Airways, TWA, and Lufthansa operated the Boeing 707-320, utilizing its capabilities to offer faster, more comfortable international flights. The aircraft's role in expanding the global reach of air travel was significant, contributing to the growth of the airline industry and the accessibility of air travel.

The Boeing 707-320's legacy is marked by its contribution to the evolution of commercial aviation. Its development and success paved the way for future generations of jetliners, setting new standards in speed, range, and passenger experience. Though its era has passed, the 707-320 remains an iconic symbol of the jet age, a period that transformed air travel and connected the world in ways previously unimaginable.

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.