Southwest Airlines (WN, Dallas Love Field) says it has revised plans to complete the retirement of its fleet of B737-300s from 2018 to the third quarter of 2017.

The Texan LCC said in a quarterly earnings report that the removal of the type would simplify its operations and 'resolve uncertainty surrounding Federal Aviation Administration (FAA) pilot training requirements for flying both the B737 Classic and B737 MAX 8 aircraft.'

"Given the Federal Aviation Administration (FAA) is not expected to complete training requirements until next year, the only solution now is to avoid flying both the Classics and the MAX," Southwest said. "Therefore, the Classics will be retired in 2017 prior to the MAX being placed into revenue service. Indeed, this is a viable and manageable solution, although not preferred. This accelerated retirement of the Classics will result in fewer aircraft and lower available seat mile (capacity) growth in 2017 than previously planned."

Southwest's B737 Classic fleet currently consists of 116 B737-300s and eleven B737-500s. The B737-500s are scheduled to be withdrawn from revenue service in September of this year.

In total Southwest has 170 B737 MAX 8s on order from Boeing (BOE, Washington National) the first of which is due for delivery during the third quarter of 2017.

According to The Wall Street Journal, Boeing has pitched a smaller version of the B737 MAX - dubbed the B737 MAX 7X - to Southwest and United Airlines (UA, Chicago O'Hare) as a possible replacement for the B737-700 of which the former operates 488 and the latter forty.

The aircraft is seen as Boeing's response to Bombardier Aerospace (BBA, Montréal Trudeau) and its nascent CSeries which is due to enter service in July this year. To compete with the A220-300, the MAX 7X reportedly features dramatically improved range and a seating capacity that outstrips its -700NextGen predecessor.