An era ended at United Airlines on 28 October as the carrier operated its last Boeing 737 passenger flight, more than 40 years after introducing the twinjet.

Flight 737, operated by 737-300 N331UA, took off from Washington Dulles and made what amounted to a farewell tour with stops at all the carrier's hubs - Chicago, Denver and Los Angeles, with the final touchdown at its San Francisco maintenance base.

United - which alongside Lufthansa was a launch customer for Boeing's narrowbody workhorse - introduced the 737-200 into revenue service on 28 April 1968, and added the -300 model in 1986 and the -500s in 1990.

At its high point United's 737 fleet totalled 220 aircraft. The aircraft's squat appearance compared with contemporary aircraft at the time resulted in many of United's pilots nicknaming the airplane "guppy".

United Airlines 737
 © United Airlines

The carrier in 2008 began the phase-out of 94 737-300/500s last year when fuel prices soared to record levels. United executives have estimated the older Boeing aircraft are 16% less fuel efficient than the carrier's Airbus A320s, predicted the retirement of the 737s should generate an overall improvement in fuel efficiency of 25%.

Currently United is reconfiguring the A320s formerly operated in its now defunct low cost subsidiary Ted with a first-class and all leather seats.

United is in the final stages of a highly anticipated decision on whether to place a large order with Airbus or Boeing for widebody aircraft and 757 replacement.

Its executives have said that the economics of the deal are crucial, and that is what the carrier is pressing the airframers for. A decision is expected by year-end.

Source: Flight International