Boeing 737-400

The Boeing 737-400 is a member of the Boeing 737 Classic series (-300/-400/-500), developed as a stretched variant of the 737-300 to accommodate higher passenger capacities. It remains one of the most widely operated variants in the 737 family, known for its reliability and efficiency in medium-haul routes.

Technical Specifications

  • Manufacturer: Boeing
  • Series: 737 Classic
  • First Flight: 1988
  • Engine Options: CFM56-3 or Pratt & Whitney JT8D (later models)
  • Capacity: Typically 140–168 passengers (depending on configuration)
  • Range: ~2,940 nmi (5,450 km)
  • Status: Production ended in 2000; many still in active service or converted to freighters.

Operational History & Significance

  • Designed to bridge the gap between the 737-300 and larger wide-body aircraft.
  • Dominated regional and domestic markets in North America, Europe, and Asia during the 1990s and 2000s.
  • Frequently retrofitted with CFM56 engines for improved fuel efficiency and noise reduction.

Notable Incidents

Legacy

  • The -400 variant set standards for single-aisle jet economics, influencing subsequent Boeing 737 NG and Boeing 737 MAX designs.
  • Many airframes have been converted to freighters or extended service life via advanced avionics upgrades.