Pilots at Southwest Airlines have joined flight attendants and ratified a tentative agreement to add the Boeing 737-800 to the carrier's fleet.

The amendable date of the current collective bargaining agreement between pilots and Southwest management will be extended by one year to August 2012, and includes potential for wage increases based on the company's performance.

Southwest flight attendants on 18 November ratified a tentative agreement reached with management earlier this year to add the larger 737 variant, whose operations would require a fourth flight attendant.

Dallas-based Southwest says it will now move forward to finalize discussions with Boeing to substitute the -800 for 737-700 positions, adding it expects to take delivery of the first aircraft in the first quarter of 2012.

Carrier vice president of strategy and planning Bob Jordan recently told ATI and Flightglobal that the 737-800 has roughly a 12%-15% cost advantage over the -700, which allows the carrier another step change in managing its costs.

Source: Air Transport Intelligence news