The 727 design arose as a compromise between United Airlines, American Airlines, and Eastern Air Lines over the configuration of a jet airliner to service smaller cities which often had shorter runways and correspondingly smaller passenger demand. United Airlines wanted a four-engined aircraft for its flights to high-altitude airports, especially its hub at Stapleton International Airport at Denver, Colorado. American wanted a twin-engined aircraft for efficiency reasons. Eastern wanted a third engine for its overwater flights to the Caribbean. Eventually, the three airlines agreed on a trijet, and thus the 727 was born. The third JT8D engine, which is located at the very rear of the fuseage, is facilitated via an s-duct leading from the duct at the front of the tail.[2] The 727 featured high lift devices on its wing, thus being one of the first jets to be able to operate from airports offering modest runway lengths. Later models of the 727 were stretched to accommodate more passengers and they ended up replacing earlier jet airliners, such as its sibling the 707, on domestic routes.

Since the 727 proved to be a reliable and versatile airliner that came to form the core of many start-up airlines' fleets, it is sometimes described as the "DC-3 of the Jet Age."

The 727 proved very successful with airlines worldwide partly because of its capability to take off and land on smaller runways while still flying medium range routes. This effectively allowed airlines to attract passengers from cities with large populations but smaller airports to worldwide tourist destinations. One of the features that gave the 727 its ability to land on shorter runways was its unique wing design. Through flap extension and leading edge slat deployment, the 727 could almost double its wing surface area, allowing it to fly with great stability at very slow speeds. The 727 also had nosegear brakes fitted in the beginning to further decrease braking distance upon landing. These were however removed later as they proved to provide little gain in braking over added weight and higher maintenance costs.

Specifications

Source: Wikipedia