Turkish Airlines' decision to order nearly 60 Airbus A320neo-family aircraft, as part of an order for up to 117 Airbus jets, appears to mark a second sweeping Turkish defeat for the Boeing 737 Max within three months.
Its agreement to take 82 firm Airbuses, and put options on 35 more, follows the stinging defection of 737 operator Pegasus Airlines to the A320neo in mid-December 2012.
Airbus had promised that the A320neo firm order backlog would exceed 2,000 by the end of March 2013, and the Turkish agreement - following a Lufthansa commitment for 70 - will tip the airframer over the threshold.
While Turkish Airlines is a large 737 operator, and still has several 737-800s and -900s on order, Airbus says the agreement is the largest contract placed by a Turkish carrier - eclipsing the deal for 75 firm aircraft signed by Pegasus.
Pegasus's deal primarily comprises the A320neo while Turkish has opted almost exclusively for the larger A321neo. If all options are exercised, the A321neo will account for 88 of the 117 Turkish Airlines aircraft.
The engine selection has yet to be made. International Aero Engines might have an advantage in the competition to power 25 regular A321s, which form part of the deal, as Turkish has heavily favoured the V2500 for its single-aisle Airbus fleet of some 75 aircraft. But the contest for the re-engined jets is wide open.
Turkish Airlines has detailed its plans to absorb 117 single-aisle aircraft over the six years from 2015.
It says it needs 13 aircraft in 2015, 14 in 2016, and six in 2017, increasing to 27, 25 and 32 in the successive three years to 2020.
Airbus secured a commitment from Lufthansa earlier this month for 35 A321neo and 35 A320neo aircraft, and could yet gain an order from Indonesia's Lion Air - a carrier whose loyalty to the 737, so far, has been demonstrated through a landmark agreement to take over 200 737 Max jets.