DALLAS — Today, in 1997, the prototype Boeing 737-800 took to the skies for the first time, piloted by Jim McRoberts and Mike Hewett. The Boeing 737-800 is the most popular model of the Next-Generation 737 family and the most widely used narrow-body aircraft.

The Boeing 737 Next Generation, often known as the 737NG or 737 Next Gen, is a two-jet engined, narrow-body aircraft built by Boeing Commercial Airplanes. It is an improvement of the 737 Classic (300/400/500) series and was introduced in 1993 as the third generation variant of the Boeing 737.

Its wings have been altered to have a larger surface area, a broader wingspan, more fuel capacity, higher maximum takeoff weights (MTOW), and a longer range. It has improved and remodeled interior layouts, glass cockpit, and CFM International CFM56-7 series engines.

The 600/700/800/900 series has four variations that can accommodate 108 to 215 passengers each. The 737-800 is the most common 737NG variant, and the Airbus A320 family is the Boeing 737NG's main rival.

The Next Gen Boeing 737

The more technologically sophisticated Airbus A320 with fly-by-wire controls was purchased by United Airlines (UA), a regular Boeing customer, which led Boeing to convert the slower, shorter-range 737 Classic variants into the more effective, longer New Generation variants.

Boeing started working on an upgraded series of aircraft in 1991. On November 17, 1993, the 737 Next Generation (NG) program was announced after consulting with prospective customers.

A Boeing 737-700 was the first Next Generation (NG) to take off on December 8, 1996. The 2,843rd 737 to be produced, this plane had its maiden flight on February 9, 1997, with pilots Hewett and Ken Higgins.

The Boeing 737−800 rolled out on June 30, 1997, and first flew a month later. The type is a stretched version of the 737-700. It replaced the 737-400. The Boeing 737-800 competes primarily with the Airbus A320. 

The smallest of the new versions, the 600 series, which debuted in December 1997 and had its first flight on January 22, 1998, is the same size as the 500. On August 18, 1998, the FAA certified the 600 series. Ten aircraft—three 600s, four 700s, and three 800s—were employed in the flight test program.

Boeing later introduced the 737-900, an even longer variant stretched to 138 ft 2 in (42.11 m). Because the −900 retains the same exit configuration as the −800, seating capacity is limited to 189, although aircraft equipped with a typical 2-class layout will seat approximately 177. The 737-900 also retains the MTOW and fuel capacity of the −800, trading range for payload. 

Alaska Airlines (AS) launched the 737-900 in 1997 and accepted the delivery on May 15, 2001. The type proved unpopular, with only 52 delivered, before being replaced by the improved 737-900ER.